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HomeMy WebLinkAboutR6180 - CERTIFYING the EIR for the WATER MANAGEMENT ELEMENT OF THE GENERAL PLAN`u • RESOLUTION NO. 6180 (1987 Series) A RESOLUTION OF THE COUNCIL OF THE CITY OF SAN LUIS OBISPO CERTIFYING THE ENVIRONMENTAL IMPACT REPORT FOR THE WATER MANAGEMENT ELEMENT OF THE GENERAL PLAN WHEREAS, the Planning Commission and the City Council have held public hearings to consider the Water Management Element and the Environmental Impact Report; and WHEREAS, the potential environmental impacts of the element have been evaluated in accordance with the California Environmental Quality Act and the city Environmental Guidelines. NOW, THEREFORE, the council resolves as follows: The Environmental Impact Report for the draft Water Management Plan, with additional information on the adverse public- service impacts of exceeding safe yield by various amounts (attached) and with comments and responses (on file at the Community Development Department), is hereby certified as adequate for the Water Management Element. This determination is based on the council finding that the Water Management Element embodies an alternative evaluated in that EIR, namely a water policy document consistent with other general plan elements. Also, the most stringent possible development- management . aspects of the Water Management Element have been addressed in that EIR, specifically in the conservation -only alternative. The council shall make a separate environmental determination for the Water Management Plan and other implementing actions prior to their adoption. With the Water Management Element, the status of impacts is as follows: Not significant: community plans and goals; geologic changes and hazards; plant life; animal life; energy use. Potentially significant, but will be acceptable with proposed mitigation: noise, air pollution, public services and utilities, drainage and flooding; water quality; historical and archaeological resources; traffic. Significant: Population growth; land -use changes, aesthetics The project is to be approved (by separate resolution) despite these significant adverse impacts, due to these overriding concerns: provision of adequate water for growth which may occur in conformance with the Land Use Element and for affordable housing as provided in the Housing Element; diversion of some growth from other places in the region that could accommodate it but with more severe impacts; expansion of the city to better control the type of development which might occur at its edges. R 6180 C, Resolution No. 6180 (1987 Series) Page 2 • On motion of Councilman Settle, seconded by -Mayor!Dun n�o :., and on the following roll call vote: AYES: Councilman I Settle, Mayor,:Duninj. Councilmembers_Dovey, Griffin and Rappa NOES: none ABSENT: none the foregoing resolution was passed and adopted this 24th day of February, 1987. Mayor Ron Dunin AT Cit Clerk Pamela Vo APPROVED: P.............`..... City Administrative,Oljficer ............... ................. ..... City Attorn y ........... ............................... Community Development Director Additional information on public service impacts The Water Management Element would establish an acceptable level of risk in exceeding the safe yield of water supplies. The chosen level of risk will affect levels of city water service. The council has considered exceeding safe yield by as much as IA. According to the element, water use should not exceed safe yield by more than 13%, and any supplemental sources obtained when water use is above safe yield should go largely to reducing the exceedance rather than to supporting additional development. City water use has exceeded the safe annual yield of existing supplies since 1984. After a public hearing in November of that year, the City Council decided to: Continue to monitor water use and reservoir conditions; Prepare the water management plan that would guide city efforts to conserve water and to obtain more water, Not restrict water use or real- estate development. In 1985, water use exceeded safe yield by about five percent, and projected 1986 use is expected to exceed safe yield by about eight percent. Although annual changes in water use are related to such variables as the weather and the economy, the continuing trend of increasing total water use has been due primarily to the construction of more houses, apartments, and businesses. When water use from projects under construction during 1986 is considered, total water use will probably exceed safe yield by nearly ten percent. As usual water use exceeds safe yield by greater amounts, water use must be reduced more frequently and by greater amounts to avoid running out of water during periods of low rainfall. The city is seeking several supplemental water supplies which could be available by the early 1990's, including conservation, drawing on Salinas and Whale Rock reservoirs in a way that would allow the combined safe yield to be slightly more than now estimated, using groundwater for landscape irrigation, and increasing the capacity of Salinas Dam. However, a major supplemental source of water, such as the coastal branch of the state aqueduct or a distribution system from Nacimiento Reservoir, probably will not be available until the mid to late 1990's (see Figure 6, which shows projected requirements and supplies). If the city's usual water use did not exceed the safe yield, reductions from usual use would probably never be needed. However, when use exceeds safe yield, cutbacks from usual use may be needed to avoid running out of water. For example; when use exceeds safe yield by ten percent, the city would have to reduce consumption by five percent in about one out of eight years. About once in 25 years it would have to reduce consumption by five percent in one year and by ten percent in the following year. About once in 100 years the city would have to cut back during four consecutive years, about five percent in the first and increasing to about.23 percent in the fourth year. Alternatively, the city might be able to quickly develop temporary or permanent supplemental supplies, such as groundwater pumping, which could forestall the need for water -use cutbacks. These estimates are based on evaluations of rainfall records, the storage and refill characteristics of the reservoirs, and observed water- conservation behavior during droughts in San Luis Obispo and other communities. pp 'T IT These estimates are derived from San Luis Obispo's 115 -year record of rainfall, including the six -year dry spell used to determine safe annual yield. A drought longer than six years may occur, though none has been experienced since 1869. Also, while the probability of a six -year drought appears small (once in 115 years), such a drought could begin any year: Less severe droughts are expected to occur more frequently. The following table shows how much and how often the city would have to reduce water use to avoid running out of water, if usual use exceeded safe yield by percentages ranges from five to 20. EXCEEDING THE SAFE YIELD - REQUIRED WATER -USE REDUCTIONS If usual water use exceeds safe annual yield by: 5% 10% 15% 20% About one year in eight, water use would have to be reduced: 5% 5% 5% 5% About once in 25 years, water use would have to be reduced two consecutive years and the maximum reduction in one year would have to be about: 5% 10% 15% 20% About once in 50 years, water use would have to be reduced three consecutive years and the maximum reduction in one year would have to be about: 10% 18% 25% 35% About once in 100 years, water use would have to be reduced four consecutive years and the maximum reduction in one year would have to be about: 10% 23% 34% 39% To minimize the risk of having to use less water than usual during droughts, the city would not exceed the safe annual yield. Or, it would have standby sources ready to use that would at least temporarily increase total safe yield. A five percent reduction in water use can usually be achieved by making the public more aware of careful water use, through information efforts or increased rates. A 15 percent reduction would probably require mandatory conservation measures, such as watering only on certain days. A 25 percent reduction would require cutbacks in landscape watering and elimination of some water uses, such as washing cars. A 25 percent reduction is difficult to achieve and maintain. A 35 percent reduction approaches the levels met by northern California communities during the 1970's drought. This reduction could be achieved only by eliminating most landscape irrigation and imposing extra charges for water use over certain amounts. Reductions of 35 percent or more are very hard to achieve and nearly impossible to maintain for a long time without significant changes in peoples' behavior and in community character. The following table, expanding the information summarized in the table above, provides estimates of water -use reductions needed during droughts likely to occur at certain intervals. It shows year -by -year reductions, assuming that the most effective water- saving efforts will not be undertaken until the community has experienced two years of below- average rainfall. Excess over Estimated reduction from usual water use safe annual yield Yr. Yr. Yr. Yr. Yr. Yr. 1 2 3 4 5 6 5% 0 0 -5% -5% -10% -10% lot 0 0 -5% -10% -18% -23% 15% 0 0 -5% -15% -25% -34% 20% 0 0 -5% -20% -35% -39% These situations could occur 4 � as frequently as once every I 8 years or so. These situations could occur about once every 25 years or so. These situations could occur about once every 50 years or so. These situations could occur about once every 100 years or so. C�� �; ���� ��������� �f���U ,�. �,�.�� WATER MANAGEMENT ELEMENT WATER MANAGEMENT PLAN ENVIRONMENTAL IMPACT REPORT FEBRUARY 1987 43-87 NO fi w I TABU OF CUNT= Paqe Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 S1m®azy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 setting. . . . . . . . . . . . . . . . . . . . . . . 7 Historical Perspective Cmmmity Character Water Situation Project Description and Alternatives . . . . . . . . . . . . . . . 11 Mill. - ft . Q . Population Growth . . . . . . . . . . . . . . . . . . . . . . 17 ViVWlil "AAULrC1{Q.d' 6 . . . . . . . . . . . . . . . . . . . . . 1$ Regional Considerations . . . . . . . . . . . . . . . . . . . 18 Camunity Plans and Goals . . . . . . . . . . . . . . . . . . 20 T and Use Changes . . . . . . . . . . . . . . . . . . . . . . . 21 Traffic. . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Air Pollution . . .27 Geologic Changes and Hazards. a 32 Drainage and Flooding . . . . . . . . . . . . . . . . . . . . 32 Water Quality . . . . . . . . . . . . . . . . . . . . . . . 32 Agriculture].. Land . . . . . . . . . . . . . . . . . . . . . . 32 Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Animals . . . . . . . . . . . . . . . . . . . . . . . 33 —stcr cal and Archaeological Resources . . . . . . . . . . 35 Aesthetics . . . . . . . . . . . . . . . . . . . . . . . . . 35 Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Public Services . . . . . . . . . . . . . . . . . . . . . . . 38 E nV'raMMtal MgMcts of Water _Projects . . . . . . . . . . . . . . 41 Envisnrmental Inpacts of Treatment and Distribution System Changes 45 Mitigation Measures . . . . . . . . . . . . . . . . . . . . . . . . 45 ly Superior Alternative . . . . . . . . . . . . . . . 51 Short-term Use/Long-term Productivity . . . . . . . . . . . . . . . 51 Caumilative Impacts . . . . . . . . . . . . . . . . . . . . . . . . 51 Irreversible Impacts . . . . . . . . . . . . . . . . . . . . . . . 51 Status of Izipacts. . . . . . . . . . . . . . . . . . . . . . . . . 53 Overriding Concerns . . . . . . . . . . . . . . . . . . . . . . . 53 Organizations and Persons Consulted . . . . . . . . . . . . . . . . 54 Preparation. . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Tables 1. Trip Generation . . . . . . . . . . . . . . . . . . . . . . . 26 2. Air Pollution Production - San Luis Obispo County - 1983. . . 28 1. Regional Setting. . . . . . . . . . . . . . . . . . . . . . 6 2. Water Supply and Consumption . . . . . . . . . . . . . . . . 8 3. Water Uses. . . . . . . . . . . . . . . . . . . . . . . . 3 4. Treatment, Storage, and Distribution . . . . . . . . . . . . . 14 5. Water Supplies and Population Growth. . . . . . . . . . . . 16 6. Urban Area Changes . . . . . . . . . . . . . . . . . . . . . . 23 7. Projected Countywide Air Pollution Production. . . . . . . . 30 8. Agricultural Land . . . . . . . . . . . . . . . . . . . . . . 34 _ INTRODUCTION California law requires the city to prepare an environmental impact report (EIR) when it considers taking an action that may significantly affect the environment. An EIR is to help the public and decision -makers understand the consequences of the action, to consider alternatives, and to incorporate features which will reduce harmful effects.. Actions include adopting plans and approving various public and private projects. This is the final EIR for the Water Management Element of the general plan, adopted in February 1987. This report was originally published as the draft EIR for a draft Water Management Plan. While these drafts were under public review, the City Council decided to include water policies -in a general plan element, closely following one of the alternatives discussed in the draft EIR. This report has been updated to respond to comments received on the draft EIR and to reflect the council's actions in adopting the Water Management Element. The Water Management Element would not authorize specific water -supply projects, but it would focus the city's efforts on several alternative ways to increase its water supply and make more efficient use of existing supplies. Making available additional water will significantly affect the community's environment, regardless of the project(s) selected.. The specific projects will also affect their settings. The city will pursue a "tiered" EIR approach, because the city is considering several projects, some of which may be pursued jointly with other agencies. State environmental guidelines allow tiered EIR's for actions that begin with adoption of a plan where general issues can be identified and that are carried outwith projects entailing specific issues that need not or cannot be resolved before adoption of the plan. Under the tiered approach, this report examines the overall effects of conserving existing or developing additional water supplies, considering the amount of water which might be obtained from alternative sources. It also outlines the types of impacts which would be associated with the projects under consideration. Separate environmental studies will be prepared for any specific projects that the council chooses to pursue.. The city also intends to use this EIR for the Water Management Plan, which would serve as a more detailed guide to implementation of water supply, storage, and treatment and distribution projects, and funding strategies. While the city considered its water policies, the county was revising its water plan.. The county determined that its water document was a study, not a plan of action, so the county did not prepare an EIR on it. As this final EIR was published, the state Department of Water Resources was starting to prepare a draft EIR on the Coastal Branch of the State Aqueduct, one of the projects reviewed briefly in this report. For more information, contact the Community Development Department, 990 Palm Street (P.O. Box 8100), San Luis Obispo, CA 93403-8100; (805)-549-7160. SUMMARY San Luis Obispo, home to about 39,000 people, is located in an attractive natural setting. Dependent on water from beyond the immediate area since the 1940's, the city again faces the decision of importing water to support growth. The policies to guide this decision and to allocate limited water supplies to competing uses are to be included in the Water Management. Element of the general plan. The City Council considered several basic water -policy alternatives, including living within the present water supplies or obtaining one or more supplemental sources. The most likely potential sources are: Conservation, using water more efficiently than now; Cooperative use of two existing reservoirs, timing use of each so the combined yield would be greater than previously; Reactivating old wells and small reservoirs, drilling new wells, or building dames on small streams in the area; Raising Salinas Dam to enlarge the Santa Margarita Reservoir; Participating with other agencies to extend the Coastal Branch of the State Aqueduct (which would bring water from Northern California to San Luis Obispo and Santa Barbara Counties), to extend a conduit from Nacimiento Reservoir, or to develop some other regional supply. The city plans to obtain enough to serve development contemplated by the general plan, which could accommodate a population of about 53,000 by the year 2015. However, because of the time required to develop major sources the city will probably not obtain sufficient water for the maximum growth allowed within the 1987 city limits until the mid 1990's. The city has rejected as infeasible the alternative of not obtaining any additional water. The city must obtain some new sources to bring water use and reliable supplies back into balance, to compensate for siltation's reductions of yield from existing reservoirs, and to acommodate land -development projects which have already received some city approval. The city has also rejected as infeasible the alternative of obtaining all potential sources. If all the water sources which have been considered were obtained, the city could grow beyond its planned open space boundary and reach a population of about 65,000 by the year 2025. To accommodate that much growth, several areas next to the city now planned to remain open would be converted from farm and ranch land to urban uses. Much of this land is prime soil for agricultural use. The availability of additional water alone will not cause growth. However, the current water supply does limit city growth and more water would lead to growth. While obtaining additional water will be an indication that the city wants to expand, the expansion would require separate actions by the city (approval of development plans for annexation areas). The potential for city growth to divert growth from other areas of the county has not been established. However, the city's accommodating growth is unlikely to significantly reduce growth in other areas of the county unless the other areas choose to ,limit their expansion. 3 The additional development enabled by supplemental water would generate more local traffic. Depending on the amount of city expansion, the number of local trips would increase about 13 percent above the 1985 total trip amount. Madonna Road, Los Osos Valley Road, Tank Farm Road, Broad Street, Orcutt• Road, Johnson Avenue, and Highway 101 would be most affected by development of the expansion areas. Drivers could expect to face longer delays at intersections along these streets, and more difficulty and increased accidents for cars using driveways along these streets. Unless county -wide growth is controlled, the increase in local trips would largely be in addition to county -wide (commuting) trips. The additional traffic will cause more noise. Trafficnoise would continue longer into the night than at present. The additional traffic and other sources which grow in proportion to population would cause more air pollution. Over the last ten years, improved effectiveness of emission control devices and better fuel efficiency have more than offset the increase in traffic, so most measured air pollutants have remained steady or slightly declined. Over the next ten years, population and traffic growth enabled by supplemental water could cancel out gains from emission controls. With growth, the city's and county's air is expected to be less clean than now and less clean than it would be if development stopped at current water limits. Additional development enabled by supplemental water would occur on land similar to areas which have already developed. Geologic and flooding hazards would be about the same as expected city-wide, though new construction would be to higher standards and therefore should be safer. Development of open lands would cause flood flows to be slightly higher along San Luis Obispo Creek south of the city. Urban development would also pollute the creeks in ways that are hard to control. If open and agricultural lands are developed, substantial changes in plants and wildlife would occur. However, no rare or endangered species would be affected. Damage to historical or archaeological resources can be avoided or reduced to acceptable levels by careful review of development. Growth enabled by the proposed supplemental water sources would change the city's physical character. Traffic, noise, and air pollution would increase and open space would. be lost. Relying on conservation or supplemental water sources yielding lower amounts within the range under consideration would result in fewer changes. Water. sources in the middle of the range would allow the city to expand to its planned open space boundary. New neighborhoods similar to existing ones would be developed. Water sources at the upper end of the range could enable development around San Luis Mountain and more intensive industrial development in the airport area south of the city. However, if the county maintains its land -use regulations, San Luis Obispo would still be separated from other communities by open lands. Accommodating growth in San Luis Obispo would not affect state or national energy consumption. So long as the growth did not exceed recently experienced rates, utilities and government services could be provided to serve the expansion areas. Expansion would. worsen the imbalance between elementary school enrollment and capacity among the city's neighborhoods, according to a study for the school district. 4 Some of the steps the city could take to reduce the impacts of growth would be taken regardless of a decision on supplemental water. Also, some impact -reducing actions are the responsibility of other agencies. The city will apply planning policies to assure that supplemental water does not automatically become a stimulus to environmentally harmful development. The city will require development of expansion areas to be phased. The expansion -phasing standards would also delay development of prime farmland. The city will also try to persuade all agencies in the county to approve major developments only when they can show that air pollution from existing sources will be reduced to offset air pollution added by the development, to prevent air quality from deteriorating. More detailed studies will be required to evaluate the environmental impacts of specific water projects. Developing new dams or enlarging existing reservoirs would flood land and could expose downstream areas to risk of dam failure. Taking water from other watersheds could also affect wildlife and farming in the other watersheds. Any pipelines to bring water to the city would temporarily disrupt the lands along the pipeline routes. While the Water Management Element could be amended at any time, the decision to obtain supplemental water is largely irreversible. Most cities subject to growth pressures like San Luis Obispo's have been unwilling or unable to control population below identifiable Physical constraints, such as water supply. Overall, living within the existing water supplies would cause least harm to the city's environment. The council is considering additional supplies so the city can grow as outlined in its general plan, to remain a regional trade center, provide housing for those employed in the city, and divert some growth from other areas where it might do more harm. Other communities in the county face similar water and growth choices. The city's water choice probably will not have much influence on other communities' choices. If all communities choose to develop substantial supplies of additional water, the county will continue to become more urban with resulting harm to the natural environment. The proposed changes to the city's water treatment plant, storage tanks, and water lines are not expected to cause significant environmental impacts. 0 0 ENVIRONMENTAL SETTING Historical Perspective. San Luis Obispo, a city of about 39,000 residents, is located between the Santa Lucia Mountains and the coastal hills of Central California (Figure 1). Originally an area of Native American settlement, it grew under Spanish influence with the founding of the mission in 1772. Agricultural development, rail transportation, military bases, a state prison and a state college, and eventually county seat employment and tourism supported expansion of the city as a trade and service center of the county. Early inhabitants used readily available water from creeks and springs in the area. Later, wells and minor stream diversions supported irrigated agriculture. The city's first reservoirs (now abandoned) were built in the early 1900's in the canyons northeast of the city. Water was first brought to the city from outside the San Luis Obispo Creek watershed in the late 1940's, from Santa Margarita Reservoir on the upper Salinas River. In the early 1960's, the city began to receive water from Whale Rock Dam near Cayucos. Community Character San Luis Obispo has an attractive natural setting. The city is surrounded by agricultural and open lands, including brush, oak, and grassland. plant communities, vineyards, and field crops. While it has not grown to connect with other communities, rural residential and commercial developments are blurring the edge between city and country, particularly south of the city. Expanding educational, legal, financial, and medical services have stimulated an influx of people. Because the city's housing supply has not expanded as quickly or as inexpensively as nearby communities, many people employed in San Luis Obispo do not live here. Commuters are adding to strains on the capacity of roads and of other communities to provide water, waste treatment, and safety services. Water Situation San Luis Obispo has a semi -arid, Mediterranean climate, averaging 22 inches of rain per year, but with wide yearly variations. Summers are warm and often foggy. Winters are cool, but rarely freezing, with rain coming mostly in December, January, and February. Measurable rain rarely falls from June through September. If the city is to accommodate increases in population and economic activity from already approved developments, it must use water more efficiently than now. If population and economic activity do not increase significantly, present water supplies will be adequate if water is used more efficiently following several years of low rainfall. If city population, the amount of economic activity, or both are to increase significantly, additional water supplies will be needed. The City's water treatment plant in Stenner Canyon purifies water to meet drinking water standards. From the treatment plant, water flows and is pumped to tanks on hillsides around the city. From the tanks, it flows through pipes to customers and to fire hydrants. The existing. network of pipes and tanks determines how much water can be delivered to various areas of the city, and therefore how far out and how far up the hillsides development can be served. 7 s Figure 2 WATER SUPPLY AND CONSUMPTION 2 0 Enlarge the area for the first step of water treatment (coagulation), and install a diffuser; provide compartments for water in the second stage (flocculation); modify the third stage (sedimentation) to better remove small particles from the incoming water and to allow water treatment to continue when repairs must be made. Improve control systems. Change the process for flushing trapped impurities from the material used to filter water in the fourth step of treatment, and change the filter material. Modify equipment for adding chemicals during the water treatment process, so liquid rather than dry, bagged chemicals could be used. Provide a generator for back-up power when utility power fails. These actions are categorically exempt from environmental review as changes to an existing facility. Additional water use of more than about 1,300 acre-feet per year will require expansion of the water treatment plant. The Water Management Plan proposes expanding the capacity of the treatment plant from 11.5 to 15 million gallons per day. This expansion would occur at the existing treatment plant. Expansion would include modifying and adding equipment, including the changes listed immediately above. An expanded treatment plant could process water from any of the new sources proposed by the plan. Building a new treatment plant would be subject to separate environmental review. Expanding the existing plant will not significantly affect its setting. Community -wide impacts would be the same as the impacts described in this report for the associated increase in water supply, so additional environmental study will not be required. The plan calls for the following actions concerning storage and distribution of treated water: Install a pressure -relief check valve near Johnson Avenue and Bishop Street to relieve pressure surges into the Bishop tank. Replace the Stenner tank with a new tank, at elevation 500 feet, near the existing Bishop Street tank. Connect water mains in Hathway Avenue and California Boulevard. Build an underground pump on Hathway Avenue north of Highway 101. Replace the pipe from Reservoir No. I north of Cuesta Park to Palm and Monterey streets. Four -thousand feet or 20 -inch -diameter pipe would be installed and an existing pipe would be replaced or lined with mortar. Rebuild the pressure -regulating vault at Grand Avenue and Wilson Street, and connect pipes in Andrews and Monterey streets. Connect pipes in Skylark Lane, or Wilding Lane, across the county hospital site to pipes near the Bishop tank. 13 Figure 4. Treatment Plant ■ Ferrini • A!I�� Highland / i i i i LEGEND • Existing Tanks to Remain OExisting Tank to be Removed ® Proposed Tank sissus New Pipe OSterner Canyon (open pond) Reservoir No. 1 (covered pond) clack Street I I I I I � I I I L • L._ r Edna Saddle I I i I I city of San WI S OBI SPO DEPARTMENT OF COMMUNITY DEVELOPMENT 990 Palm St. / P.O. Box 321, San Luis Obispo, CA 93406 14 V I I I I I NBishop Terrace Brill "w em %l1 111 Islay TREATMENT, STORAGE, & DISTRIBUTION FACILITIES Modify the Alrita area pump station and install a check valve near the corner of Alrita and Flora Streets. Restore a pipe in California Boulevard between Foothill and Hathway, extend a 20 -inch pipe from Highway 1 and Westmont to Cuesta Drive and Foothill Boulevard, move a pressure -reducing vault, and tie the 20 -inch cross-town feeder main into local mains at Serrano and Ramona Drives, so this part of the system can accommodate increased flows to serve growth in other areas of the city. Install a larger pipe to serve a fire hydrant on Serrano Drive Install a check valve at the site of abandoned pumps on Foothill Boulevard, to increase reliability of service in the Patricia Drive area. Modify service to the Highland pressure zone, to avoid excessive pressure that would result from changes made to accommodate the most recent Ferrini tract. Continue to replace undersized pipes in the downtown area, and shift some areas which are now part of the downtown pressure zone to other pressure zones. Continue to replace substandard pipes and provide loop connections within other existing pressure zones, and install valves which will make available sufficient water for fire fighting. The locations of principal facilities are shown in Figure 4. With the exception of replacing the Bishop Street tank and the pipe from Reservoir No. 1, these storage and distribution projects are adequately evaluated in this EIR, so no additional study is contemplated. Replacing the Bishop Street tank and the Reservoir No. 1 pipe will be evaluated when more specific project descriptions are available. 15 ENVIRONMENTAL IMPACTS OF CITY GROWTH Population Growth The choice of supplemental water supply is essentially a choice of how much the city will grow. With the "no project" or conservation alternatives, city population would stabilize at about 39,000 people. The rate of growth would slow during 1987 and stop before 1990. New water sources would be used to keep water use within safe yields. The number of people moving into the city would equal the number moving away. (The city of San Luis Obispo appears to have a natural population growth rate near zero, according to household size and population age data from the 1980 census. County -wide, in the early 1980's, over 85 percent of population growth was due to people moving to the county.) A single supplemental water source yielding 1,300 acre-feet per year would enable city population to increase up to about 40,500 people. This and all following population figures assume that 995 acre-feet per year from any supplemental water source will be allocated, over the long term, to replace losses from reservoir siltation, and that this amount of water will not be available to support city growth. At the other extreme, a source yielding 6,000 acre-feet per.year would enable a city population increase of about 64 percent, to a total of 64,000. The Water Management Element calls for sources to enable 40 percent growth, to about 53,000 people. Each additional acre-foot of water per year would support five additional residents, or about two average households, along with associated commercial and governmental uses. Growth Inducement Developing supplemental water supplies will lead to growth in these ways: Additional water will enable more commercial and industrial development, which will draw more residents. 2.. Additional water will enable more residential development, which will accommodate more people. 3. The additional population will demand more services. Service demands will generate more employment and business activity, which in turn will draw more residents. Growth -inducing effects will depend on how much water is secured and how soon it is made available. A large source will enable more growth. A large source will further postpone the time when the city will face another resource limit. A source which can be developed soonwould enable current growth trends to continue, while a source which could not be developed for several years would reduce the growth pressures resulting from a continuously expanding population. None of the major new water supply projects are expected to deliver water before the mid 1990's. Therefore, any choice of major, long-term supplies entails a period of more deliberate conservation and slowed increases in water demand from development. 17 The reliability of a water source can influence growth. Alternative water sources are not equally reliable. For example, state water engineers estimate that the State Water Project would be able to deliver all the water called for by contracts with agencies in about three out of ten years. In other words, while the state project could supply more water than its "firm yield" in some years, in seven out of ten years the state project could not deliver all the water each contract calls for, so some agencies would have to conserve or use other sources. The effects on San Luis Obispo of a state water shortfall have not. been determined. Generally, safe-annual-yield figures reflect the reliability of a water source, since they take into consideration the driest period on record.. In many years, the available yield would be higher than the safe .yield, prompting agencies with growing water demand to use more than the safe annual yield. They would do so hoping that rainfall in the near future would be near or above average, and that conservation measures could extend remaining supplies. This tendency, already evident in San Luis Obispo, could result in population capacities higher than estimated in this report. Regional.Considerations Citizens and government officials hold varying opinions on whether population growth in the city or in the county is inevitable and what growth rates are desirable. Opinions also differ on how much the city's growth (or lack of it) affects the rest. of the county. Some people believe the county population will. increase regardless of individual agencies' water choices. Others believe the city can and should lead in the effort to limit growth. Clearly, some of the pressures for growth will continue. Many people will want to move from severe to mild climates, from interior to coastal areas, and from more polluted to less polluted places. The employment shift from manufacturing to service industries is expected to continue. These factors will maintain growth pressures on the city and county. On the other hand, expected declines in the number of people aged 18 to 25 years could mean fewer college students and fewer prison inmates. Declining oil prices may delay offshore oil development, so employment from that activity would not replace the Diablo Canyon powerplant workforce. If the city and county populations continue to increase, the increase may depend largely on retirees relocating, tourism, and light manufacturing. The city and county can control these activities through land-use and development-review decisions, though they may choose not to. The rates of population growth projected in planning studies are not inevitable. If local governments in the county put as much effort into controlling growth and they do into accommodating growth, in -migration could be substantially reduced. To some extent, if the city does not accommodate business and population increases, other jurisdictions within the county will. In some ways, San Luis Obispo can accommodate growth with less overall damage to the environment than if the growth. occurred in other areas of the county. Increased employment and enrollment in San Luis Obispo without a corresponding increase in housing could result in more commuting, and therefore more air pollution. Some believe that higher density development within the city will prevent rural residential sprawl outside the city. is While partially true, these conclusions do not describe the full situation for the following reasons. Uniform application of water limits: Limited water supplies need not constrain housing development more than other types of development. Under planned development controls, tourism, manufacturing, and institutions would be subject to the same limitations as residential development. While some growth -inducing activities could expand without additional water, they would not significantly change the imbalance between housing and employment among the county's communities. Service employment: Within a local area, population growth causes more growth. When the population of the city and county grow, the additional demand for goods and services causes businesses and agencies to expand. Also, a larger population can support more specialized services, so new businesses open. Slowing or stopping city population growth would help interrupt this cycle. In addition, as other community's populations increase, their dependence on San Luis Obispo for trade and services would decline. Different costs: In choosing a place to live, those employed in San Luis Obispo consider other location's housing costs and their trip -to -work costs. Housing in some other places will continue to be less expensive than in San Luis Obispo. Therefore, so long as those places accommodate residential development as they recently have, some additional workers in San Luis Obispo will commute regardless of housing construction in the city. Different preferences: Those who desire and can afford an oceanside, acreage, or rural hillside setting will continue to do so even if the city accommodates higher density housing in developed areas or detached housing in expansion areas. Limits on rural subdivisions, not city expansion, would prevent the environmental impacts of rural -residential development. Generally, as cities grow they attract people who want to be close to city jobs and services but who want to live in a rural setting near the city. Since 1973, the total county population has grown faster than city population. In general, any growth within the county creates growth pressures within the city, since the county government center and many specialized stores and services are located in San Luis Obispo. Housing development in San Luis Obispo does reduce pressures for housing• development in surrounding communities. However, the relationship between city and county population growth is not simple and mechanical. If the city obtains a water source located within the county, that source would not be available to support growth elsewhere in the county, so growth would tend to shift to the city. Also, the city would be less likely to participate in a county -wide water project, Which would include the coastal branch of the state aqueduct. Since the city's 4,100 acre-feet per year allotment from the State Water Project would be about 18 percent of the county -wide yield of 23,000 acre-feet per year, the city's .nonparticipation would not significantly reduce the feasibility of the county -wide project. If the city did not participate in the state project but other agencies did,, and the city developed its own source, the total amount of water available within the county would be higher, leading to more growth. (Other agencies in the county are interested in the city's share of the state project yield.) 19 The effects of various combinations of water decisions by the city and other agencies are largely speculative. Overall, the city's choice in adopting the water management plan will probably not have a significant effect on county -wide growth. However, the water choices of other agencies within the county are very similar to the city's. Their water decisions will be choices of how much growth to support. Their common decision or the combined effects of their individual choices will have a significant effect on growth Within the whole county over the next forty years. Community Plans and Goals Land Use Element The city's policies on growth are stated in the Land Use & Growth Management Element of the general plan, adopted in January 1977. That element says yearly city population growth should not exceed four percent during the 1970's, two percent during the 1980's, and one percent during the 1990'x: It calls for limits on the factors causing growth -- creation of jobs and levels of college enrollment -- and says the city's population growth rate should be about the same as the state's (recently about two percent per year). During the 1960's and 1970's, the county as a whole grew faster than the state, and the county population continues to grow about twice as fast as the state's. During the 1970's the city did not grow as fast as predicted. Also, the base population used in the Land Use Element discussion was higher than actual. So, the Land Use Element's anticipated population of 55,000 in 1997 now appears too high, as a statistical projection and in comparison with water supplies. The Water Management Element contains a revised population projection, which indicates about 53,000 people by the year 2015. The Land Use Element was based on the assumption that current water supplies could support a population of about 42,000, and that a conservation program would enable service to a maximum of 46,000 people. (The Land Use Element assumed per -person water use would be slightly lower and safe annual yields would be somewhat higher than currently estimated.) The element shows areas for various land uses which could accommodate a population of about 45,600 within the 1987 city limits and a population of about 53,000 within the urban reserve line. The urban reserve line is the limit to outward expansion of the city. The element favors filling in vacant land within the city and minimum outward expansion. The Land Use Element map shows appropriate uses for areas in and around the city, but it does not say they should be developed in a certain time. Large areas outside the current city limits are designated as potential expansion areas. Those areas are to be kept open or in agricultural use until urban development is appropriate. The element says these areas should not be developed unless the water demands of the expansion areas can be met in addition to the demands from all the potential development within the city limits. .. The element does not set minimum population growth rates nor minimum or maximum desired city population. The Land Use Element could be implemented with any of the water supply alternatives, from "no project" to 6,000 acre-feet per year of supplemental water. A total of 2,335 acre-feet per year of supplemental water would allow maximum development of the land -use designations inside the 1987 city limits. Any smaller amount of water would not. A total of 3,905 acre-feet per year of supplemental water would allow maximum development of all expansion areas within the urban reserve line. Alternatives yielding more than 3,905 acre-feet per year would enable development beyond that designated in the Land Use Element. The Land Use Element. does not assume indefinite expansion of the city. It relates city growth at any time to the availability of resources. FIE Housing Element The general plan Housing Element, most recently amended in March 1987, calls for housing construction averaging 300 dwellings per year during the 1980's, with a resultant 1990 population of about 42,000. Water supplies yielding more than about 2,000 acre-feet per year could support housing production goals. The housing element anticipated water supply limits in calling for residential use to have first priority if water for new development must be rationed. Providing water for expansion of Cuesta College could conflict with policy discouraging institutional expansion until housing supply can catch up with employment. Growth Management Regulations The Residential Growth Management Regulations, a Municipal Code chapter adopted in 1982, can limit development of large residential projects after the housing growth rate has exceeded two percent per year for two years. The regulations try to reserve resource capacity for the most affordable and the most conveniently located projects. Selection of any of the water alternatives would not directly affect these regulations. The no -project or conservation -only alternatives would require building limits below those set by the regulations. Alternatives yielding more than about 2,300 acre-feet per year could add to pressures to repeal or modify the regulations. The Water Management Element outlines.new growth regulations intended to keep water demand from exceeding supplies by an unacceptable margin. The Residential Growth Management Regulations would be suspended while these new regulations are in effect. Conservation Element The general plan Conservation Element (adopted 1973) says: Population growth and development policies should reflect adequacy of the water supply; The city should consider full development of local water resources; Water management should be reviewed and coordinated, with an effort to conserve present and future sources; Any schemes to import water should be part of a regional plan; Development of prime agricultural lands should be avoided (see discussion of land -use changes, below). Current Land Use Element policies together with Water Management Element are consistent with this element. In summary, sources yielding a total of 2,000 to 4,000 acre=feet per year would coincide most closely with growth outlined in the city's general plan. Land Use Changes Obtaining additional water will enable development and changes of land -use. The extent of the changes would be proportional to the amount of water available, unless the city chose to keep development under the amount which could be supported by water sources. 21 The timing and character of the changes will depend on the city's land -use decisions. In general, water supply is a more definite constraint for land -use changes than land -use policies are. Water supply limits are considered less flexible and more time-consuming to change than land -use policies or regulations. The no -project alternative would entail minimum land -use changes. Projects which have already received building permits would be completed. Major new projects would not be approved. Existing buildings would be replaced with new buildings having similar water use, but the city would not expand outward. Open lands would not be converted to urban uses. Some open lands outside the city limits would be converted to low -intensity uses which could be supported by groundwater. (This can happen with any city water alternative.) With the conservation alternative, some vacant land within generally built-up areas of the city would be developed. The first five phases of the Edna -Islay area might be completed. Several older residential and commercial areas would be replaced with more intensive development. The city would probably accept some minor annexations (where open space on hillsides would be preserved as a tradeoff), but no major annexations would be allowed. (All these conclusions assume current general plan policies remain in effect). Sources yielding more than 2,300 acre-feet per year would lead to development of about 92 acres beyond currently subdivided areas (the last four phases of Edna -Islay and the southern 30 acres of Higuera Commerce Park). Any source or sources yielding more than 2,300 acre-feet per year would enable annexations and development outside the existing city limits but within the urban reserve line. As discussed under Regional Considerations, the no -project and conservation -only alternatives may cause more land -use changes in other areas of the county than water choices leading to more city growth. Additional expansion of "bedroom communities" which do not have water or sewer limits could be one result. With a source yielding up to 3,900 acre-feet per year, the city could expand out to the urban reserve line. All the major expansion areas would be developed. They consist of the following (see Figure 6): The Irish Hills area., about 120 acres west of Los Osos Valley Road and south of Madonna Road. About 590 apartments and houses would extend from Los Osos Valley Road back to the lower slopes of the Irish Hills; and from Madonna Road about one-half mile south, to the Auto Park Way area. This land is now used for field crops, pasture, and grazing. The Dalidio area, about 200 acres bounded by Madonna Road, Los Osos Valley Road, Highway 101, and the Madonna Road shopping centers, which would be developed with about 980 apartments and houses. This land is currently used for irrigated.field crops and pasture. The Margarita area, about 100 acres around the eastern end of Margarita Avenue, which would be developed with about 490 apartments and houses. This area is currently used for grazing. The Orcutt area, about. 200 acres east of Orcutt Road and Johnson Avenue, which would be developed with about 980 apartments and houses. It is currently used for grazing and houses on large lots. 22 Figure 6. -- city Of San WI S OBISPO DEPARTMENT OF COMMUNITY DEVELOPMENT 990 Palm St. / P.O. Box 321, San Luis Obispo, CA 93406 23 URBAN AREA CHANGES Several minor expansion areas with a total of 100 acres would accommodate about 280 houses. These areas are currently used for grazing and houses on large lots. Also, part of the "Maino/Madonna" area near San Luis Mountain, which is now outside the city limit, could be developed with tourist -commercial uses. A partially developed industrial area along Sacramento Drive could also be annexed. The estimates of dwelling and population capacity assume that 30 percent of the major expansion areas would be roads, parks, and other nonresidential uses, and the remaining 70 percent would be developed at a maximum seven dwellings per acre. The estimates for the minor expansion areas also assume 70 percent of the land would be available for residential use, but that the maximum density would be four dwellings per acre. The areas which could be urbanized with a 3,900 acre-feet per -year water source total 720 acres, or about 1.1 square miles. With a source or sources yielding 6,000 acre-feet per year, up to 980 acres could be urbanized. Also, 260 acres more than are now included within the urban reserve line could be developed. Additional expansion areas beyond the urban reserve line might be; The Los Osos Valley, north of existing development (200 acres); The area between Los Osos Valley Road and the Irish Hills, south of the identified Irish Hills expansion area shown on the Land Use Element map (50 acres); Land east of the county airport and south of the Edna -Islay area (200 acres); Land south of the Orcutt expansion area (100 acres) Land west of the Foothill saddle in the vicinity of O'Connor Way and the western slopes of Bishop's Peak or San Luis Mountain (300 acres); More intensive industrial development in the vicinity of the airport or residential development south of the airport. Most of these areas are now used for grazing, nonirrigated crops, or dwellings on large lots. Traffic The following analysis assumes that regional growth will be largely independent of the city's choice of supplemental water - that other areas in the county will not grow significantly more or less as a result of this city's growth choice. Therefore, travel between communities will not be substantially different under the various alternatives. This assumption is plausible since availability of water will affect both employment potential and housing potential, the factors responsible for commuting between areas. The analysis also assumes that long-distance travel through the region will not be significantly affected by the city's growth choice. 24 The following trip generation rates were used: Single-family dwellings: 10 total trips per day per dwelling. City surveys have found 10 to 12 trips per day in neighborhoods with single-family houses. The low estimate was used since increasing traffic congestion, fuel costs, and use of alternatives to the car may reduce trip generation. Multifamily dwellings: 7 trips per day per dwelling. City surveys have found 6 to 8 trips per day in areas developed mostly with apartments. The following assumptions about dwelling types in expansion areas were made: About one-third of the total dwellings would be multifamily apartments or condominiums, in the range of 12 to 15 dwellings per acre, and generating on average 7 trips per dwelling. About one-third of the total dwellings would be single-family houses, in a range of 7 to 10 dwellings per acre. Some would be conventional housing and some would be mobile homes. Since the trip generation rate for mobile homes appears to be the same or slightly lower than multifamily housing, an overall trip generation rate of 8 trips per day was used. - About one-third of the dwellings would be conventional single family houses, in the range of 4 to 6 dwellings per acre, generating 10 trips per day. The Edna -Islay area was evaluated according to the mix of dwelling types allowed by the specific plan for that area. Table 1 shows the trips which would be generated in each of the major expansion areas. A source yielding up to 5,000 acre-feet per year would enable development of all the expansion areas named above and would result in 28,570 more local trips per day than the no -project or conservation alternatives. A source yielding 6,000 acre-feet per year would enable more development than contemplated by the general plan and would result in about 44,000 more trips per day than the no -project or conservation alternatives. About 335,000 vehicle trips were made in and through the city each day in 1985. The proposed water sources would therefore lead to a local traffic increase of about 13 percent citywide. Development of the named expansion areas would directly and substantially add to traffic on the following major streets: Edna -Islay: Broad Street from Tank Farm Road to South Street; Orcutt Road from the extension of Tank Farm Road to Johnson Avenue and to Broad Street; Johnson Avenue from Orcutt Road to Monterey Street; Tank Farm Road from Broad Street to South Higuera Street. Irish Hills: Los Osos Valley Road, from South Higuera Street to Royal Way; Madonna Road; Highway 101 from Los Osos Valley Road to Santa Rosa Street. 25 Dalidio: Madonna Road; Highway 101 from Los Osos Valley Road to Santa Rosa Street; _ Los Osos Valley Road from Royal Way to South Higuera Street. Margarita: Margarita Avenue; Prado Road; South Higuera Street from Los Osos Valley Road to Marsh Street. Orcutt: Orcutt Road; Johnson Avenue; Broad Street from Orcutt Road to South Street. TABLE I TRIP GENERATION Exnansion Area Total Dwellings Total Trins ger Day Edna -Islay Phases 6-9 353 3,260 Irish Hills 590 4,910 Dalidio 980 8,160 Margarita 490 4,080 Orcutt 980 8,160 Subtotal 3,393 28,570 Expansion beyond Urban Reserve 1.274 15:290 TOTAL 4,667 43,860 The city has not prepared a traffic assessment for each road section. However, road capacity would generally be adequate between the intersections of major streets. Delays are expected to increase even with planned road widenings at the intersections. Where drivers now wait through one signal cycle to proceed, they may have to wait through more than one. Also, drivers will have increasing difficulty turning onto the major streets from driveways and cross streets where signals are not provided. Noise The additional traffic would add to traffic noise. The increase will be most noticeable on roads that now have little traffic, such as Orcutt Road east of Johnson Avenue and Los Osos Valley Road west of Higuera Street. A larger city population supporting more commercial activities will also cause traffic noise to continue longer into the night than it does now. r� Ami rr Pollution The city's air quality depends on its weather and landforms, the number and activity of air -pollution sources, and the rate of pollutant production from each source. Air pollutants can harm human health and enjoyment, plants, and materials. Their harm is in proportion to the pollutant's concentration (how much pollutant occupies a given space) and exposure (how long something experiences a certain concentration). Weather and Landforms San Luis Obispo occupies a local air basin formed by the hills and mountains surrounding the Edna, Los Osos, and El Chorro valleys. Several weather conditions cause San Luis Obispo's air to become a stable mass at some times of the year and day. The top of the air mass often is lower than the ridges of surrounding hills, resulting in a relatively small space for pollutants to disperse and higher pollution concentrations than usual. Therefore, San Luis Obispo's freedom from smog cannot be explained by unique weather conditions. The layer of haze which forms on still fall days and the odor of exhaust which mixes with the fog on summer mornings show that San Luis Obispo can feel the effects of air pollution if sufficient pollution is produced. San Luis Obispo also occupies a larger air basin which includes San Luis Obispo and northern Santa Barbara counties. Air pollution sources in the city contaminate this basin, and other sources in the basin affect the city. Air Pollution Sources Many sources produce pollutants within the city's air basin. Table 2 shows which sources are responsible for five types of pollutants: Organic gasses include various compounds of hydrogen and carbon. Some of them react with other compounds in the presence of sunlight to form smog; some may cause cancer. Particulates are small particles which obscure visibility and which may settle in the lungs. Oxides of nitrogen form when air supports combustion at high temperature and pressure (as in engine cylinders). Some of them give smog its characteristic yellow-brown color. Some form acids with moisture in the air, stinging eyes and lungs. Sulfur dioxide is formed when fuels containing sulfur are burned. With moisture in the air it forms acids. Carbon monoxide is a product of incomplete combustion. It replaces oxygen in the blood, causing fatigue or disorientation at low concentrations and death at high concentrations. 27 O O Li O D\ O N to M l C C to O I v N v t0D v v V H v M Ln to M Ln N t- O co a �o �o N M rl C 61 Ln N 01 H H N N M m O O Li O D\ O N to O C C to M O rl N N C N C to t- O wN v C N M � rl N W O o ems• -W v C rl O M M all co rl O � Ln M E U �H+ M r1 N O H OOi r-1 O O O D Ln OM Ln �o n N Ln Ci N M 0 0 0 0 i --I v M M N a p �0 N C O Na\ Itr a% M O N N co U +r O m a .I a� b ca rl vi ��cc rI En bW �'� 14 oa�i 28 Air Quality Conditions and Standards The .Air Pollution Control District (APCD) has measured air quality in San Luis Obispo since 1970, and at other locations in the county for various periods. The federal government and the state government have set standards for pollution exposure to protect public health. The following discussion relates measured air quality to the standards, with comments on the reasons for observed trends, for three pollutants. Oxides of nitrogen have not exceeded state or federal standards within the county. San Luis Obispo has the highest concentrations in the county, as expected from the concentration of vehicles. Highest concentrations occur during the winter. Since 1970, average concentrations of nitrogen dioxide have remained about the same, while maximum annual hourly concentrations have declined slightly. The increasing proportion of newer cars with more effective emission -control devices has apparently balanced the increase in vehicle -miles travelled. Carbon monoxide levels exceeded state and federal standards several times during the early 1970's. Since 1975, the standards have not been exceeded. Highest concentrations follow the morning and evening commute times during the winter. Carbon monoxide levels have declined steadily since 1970. Vehicles' emission -control devices have more than offset the increase in vehicle -miles travelled. Ozone is a chemically active form of oxygen which attacks lung tissues, vegetation, fabrics, and rubber. Ozone is formed as hydrocarbons react with oxides of nitrogen in sunlight. Violations of the national standard occur about once per year in the county. The state standard was violated eight times during 1981 and seven times in 1982. Concentrations in San Luis Obispo have remained generally unchanged since 1970. Concentrations elsewhere in the county have declined slightly. Vehicle emission controls, better fuel economy, and vapor recovery devices at service stations have apparently balanced the increase in vehicle use. Impacts and Air Quality Projections When the city evaluated air quality impacts for the 1977 Land Use Element, the California Department of Transportation (Caltrans) had predicted air quality assuming population growth consistent with the element:. The projections showed significant declines in concentrations of carbon monoxide, nitrogen dioxide, and oxident from about 1972 to 1980, then continued low concentrations through 1995. The predictions assumed that emission controls would more than offset the increase in population (vehicle use). The state Air Resources Board, however, observed that during the mid -1980's growing population throughout the state would begin to balance the improved emission -control effectiveness. Measurements have proved the Caltrans predictions to be overly optimistic. Current trends indicate that the Air Resources Board was correct. The dramatic gains in.source control have been made. Improvements in control technology and enforcement during the next 10 to 20 years will be more than offset if population continues to grow. Air pollution officials consider the three pollutants discussed above to be dependent on population. (Other pollutants, such as those from power plants or agricultural practices, are largely independent of county resident population.) Therefore, future. production and concentrations of these pollutants will be correlated with population, within the county as a whole and within the city. Figure 7 shows how county -wide pollution production is expected to increase with various increases in population. Since 29 C6 H C Vl 0 50 40 30 20 10 6 4 2 Figure 7. PROJECTED COUNTYWIDE POLLUTANT PRODUCTION BEY 2000 1995 1990 POLLUTANT F143 1 44,400 I 45,000 I 46,500 I =W, 1. PARTICULATES 5,280 I 5,4 4,450 70 I 15 10 5 30 20 10 30 20 10 11,170 1 11,760 ORGANIC GASES 23,840 i,asozoss0 16,4x0 OXIDES OF NITROGEN 43,900 57,55037,130 1 37,070 SULFUR DIOXIDE L;A11 Source: S.L.O. County Air Pollution Control District 30 MONOXIDE O O O m = y •m i c e gt Q. �w �a0 ao.0 :ao,c7 POLLUTANT F143 1 44,400 I 45,000 I 46,500 I =W, 1. PARTICULATES 5,280 I 5,4 4,450 70 I 15 10 5 30 20 10 30 20 10 11,170 1 11,760 ORGANIC GASES 23,840 i,asozoss0 16,4x0 OXIDES OF NITROGEN 43,900 57,55037,130 1 37,070 SULFUR DIOXIDE L;A11 Source: S.L.O. County Air Pollution Control District 30 MONOXIDE weather conditions are not expected to change, pollution concentrations will vary in proportion to pollution production. While pollution concentrations cannot be predicted with certainty, the production of pollutants is expected to exceed current levels with I0 to 42 percent growth county wide for all major pollutant categories. Even with stable county population, maintaining air quality may be difficult considering such factors as offshore oil development and efforts to reduce federal fuel -efficiency standards. 31 ja Changes and Hazards Urban development resulting from additional water will not change San Luis Obispo's underlying geology. Surface soils will be changed as open lands are developed. Sandy soils will be put on natural clays and soils will be compacted. Urban development will occur in areas geologically similar to areas that have been developed. No greater geologic hazards are expected. While the whole city is subject to earthquake risks, new construction will be more able to resist shaking and settlement than older buildings. Drainage and Flooding Many places in San Luis Obispo are occasionally flooded. Urban development will expose more people to the local risk. City development standards are expected to prevent serious damage or risk to life in newly developed areas from all but the most extreme (infrequent) floods. Urban development will affect areas downstream along San Luis Obispo Creek. More pavement, roofs, and irrigated landscaping will cause runoff from rain to flow more quickly than when agricultural and open lands were undeveloped. Flood levels from a certain amount.of rainfall will be somewhat higher, and they will probably be reached sooner after a rain starts to fall. A preliminary evaluation shows that development would cause runoff to increase from one percent (Margarita area during a 50 -year storm) to seven percent (Dalidio area during a 25 -year storm). These percentages describe flows at the lowest point in each expansion area. Percentage increases would be smaller along San Luis Obispo Creek, which drains a much larger area.. Water Quality Urban development in San Luis Obispo will not significantly affect groundwater quality, since storm drainage flows into creeks and since sewage is treated by the city before waste water flows into the stream. However, urban development will affect water quality in streams. If land north of Laguna Lake is developed, the lake will be affected as well. Tire residue, oil, and some fertilizers and pesticides from developed areas run into streams and lakes along with rainwater. Rainwater and deliberate washing sometimes carry paint and cement residue and soil from construction sites into storm drains and creeks. Usually, the amounts of these pollutants do not significantly affect water quality in the city. Additional development made possible by supplemental water probably will not significantly change average water quality. However, individual incidents, such as fuel and chemical spills and runoff from construction sites, do frequently pollute San Luis Obispo's creeks. These incidents affect the smell and appearance of the water as well as fish, insects, amphibians, and birds living in and along the creeks. If the expansion areas are developed, more incidents can be expected. Agricultural Land Much of the land which would be urbanized as a result of the city obtaining additional water is prime agricultural land. San Luis Obispo's moderate climate, good soils, rainfall, and limited groundwater allow cultivation of multiple annual crops such as garbanzo beans and snow peas. Figure 8 shows the location of Class I and II soils which have been and which probably would be developed. Class I and II soils, according to the U.S. Department of Agriculture, have few limitations for agricultural use because of their inherent fertility, texture, depth, and drainage. 32 All major residential expansion areas and the southern 30 acres of Higuera Commerce Park contain Class I and II soils and have supported some cultivation or intensive grazing. Most of the best soil is in the Dalidio expansion area, which has been cultivated' continuously for about 70 years. Throughout the San Luis Obispo area, growers who lease land continue to cultivate parcels too small to provide the entire support for a farm household. Urban development on and near the parcels is the primary threat to continued agricultural use. San Luis Obispo's agricultural setting and agricultural production are not unique. Similar conditions exist throughout the central coast. However, agricultural lands are similarly threatened by urban development in most locations. Supplemental water sources yielding 4,000 acre-feet per year would lead to development of about 500 acres of Class I and II soils. The proposed sources yielding 6,000 acre-feet per year could lead to development of about 1,200 acres of Class I and II soils (nearly all the remaining prime land surrounding the city and about one percent of all Class I and II soils in the county.) Plants Urban development enabled by supplemental water will cause substantial changes to plant life. Plants normally grown in residential areas will replace field crops, grasses, and low -growing leafy plants and brush. Existing large trees, such as oaks, sycamores, and eucalyptus would probably remain or be replaced. The named expansion areas do not include any rare or endangered plants though serpentine rock hillsides around the city support several rare or endangered plants. Plants growing in the expansion areas grow in other places in the county. Development of the expansion areas would not significantly change the county -wide acreage of such plants. Urban development throughout the county is changing the balance between urban vegetation and agricultural and natural vegetation. Animals Animal life will be affected by changes in plants and water quality. Plants normally grown in residential areas support different wildlife from that found in agricultural and open areas. Animals which need wide hunting areas and undisturbed nesting places will be replaced by domestic animals and those adapted to living in cities. There will be fewer quail; kildeer, doves, owls, hawks, snakes, large mammals, and reptiles and amphibians. There will be more cats and dogs, small mammals, and birds such as linnets, sparrows, and blackbirds. None of the expansion areas are known to support support rare or endangered animals. However, the rare or endangered red -shouldered hawk, Pacific pond turtle, red -legged frog, and two -striped garter snake live in the vicinity of the city. As with plant life, county -wide populations of animals will not be significantly affected by development, but natural animal populations county -wide are declining as open lands are developed. 33 v1 %w� h '. Historical and Archaeological Resources None of the water alternatives will significantly affect historic buildings in the city. Neighborhoods with historical qualities will not be affected either. Farms and ranches at the edges of the city, many of which are or were recently owned by founding families, would be converted to urban use with the proposed supplemental water supplies. As discussed below under Aesthetics, many resident's sense of San Luis Obispo's historical identity may change with major expansions and increased traffic. Archaeological resources -- traces of Chumash settlement before Spanish colonization -- may be affected by city expansion. The city usually requires archaeological assessments during review of major developments and steps to identify and preserve artifacts which may be found during construction. Aesthetics Most city residents value San Luis Obispo's compact form, defined by hills and separated by open lands from other communities. The clean air and the lack of congestion in relation to more developed areas are other attractive characteristics. An active, pedestrian -scale downtown commercial area, well preserved older neighborhoods, and relatively slow conversion of open lands to urban use are also cited as desirable physical factors contributing to the sense of San Luis Obispo as a special place. Citizens are concerned about the pace of development throughout the county and the eventual size of the city. A majority of residents, when given the opportunity to vote directly, have favored voter approval of annexations (Measure G to amend the City Charter, approved in June 1978) and minimum outward expansion (Foothill and Ferrini annexations, rejected in November 1978). (A state court later held the Charter measure invalid and ordered the annexations.) The no -project and conservation alternatives would result in no significant aesthetic impacts. The overall form of the city and local traffic levels would not change significantly. Conservation, cooperative use of the existing reservoirs, and expansion of Salinas Reservoir would produce few changes in city form. Neighborhoods which have been started at the edges of the city would be completed and relatively little agricultural land would be developed. Local traffic levels would increase, but would remain within the capacity of existing streets and proposed widening projects. Adding water from the state project, as proposed, would enable the city to expand over agricultural land bordering its southern and western edges. New neighborhoods would be created. The perception of the city as a community surrounded by peaks would give way to an image of peaks surrounded by a city. Noise and congestion from traffic would increase. However, if the county maintains its land -use regulations, San Luis Obispo would continue to be separated by open lands from Morro Bay and Baywood/Los Osos and from the Five Cities area. Even with substantial growth, in comparison with metropolitan areas San .Luis Obispo would remain attractive to those moving from metropolitan areas. This area would be less attractive than now to many residents who had seen it change. A gradual pace of development would make the changes less disruptive. Obtaining one large water source would be more likely to accommodate rapid expansion than successively obtaining several smaller sources as previous supply limits were reached. 35 The 26,000 additional residents_ enabled by the largest combination of supplemental water sources would have a significant impact on the character of the city. Accommodating an equal population increase within a metropolitan area would riot have an equivalent effect on the character of the metropolitan area. The city requires architectural approval for new multifamily housing, housing tracts, and commercial and industrial developments. Architectural review could result in attractive individual developments but it would not completely mitigate the changes in overall community character caused by growth. Architectural and landscape standards can reduce but not eliminate the aesthetic effects -of land -use changes over large areas. If adhered to, the growth management regulations would keep the pace of change relatively gradual, at least through 1999. The city's plans and regulations do not establish a maximum desirable growth rate for the years after the year 2000. Energy Accommodating more people in San Luis Obispo will not affect state or national energy consumption. Utilities The Water Management Element would establish an acceptable level of risk in exceeding the safe yield of water supplies. The chosen level of risk will affect levels of city water service. The council has considered exceeding safe yield by .as much as 15%. According to the element, water use should not exceed safe yield by more than 13%, and any supplemental sources obtained when water use is above safe yield should go largely to reducing the exceedance rather than to supporting additional development. City water use has exceeded the safe annual yield of existing supplies since 1984. After a public hearing in November of that year, the City Council decided to: Continue to monitor water use and reservoir conditions; Prepare the water management plan that would guide city efforts to conserve water and to obtain more water; Not restrict water use or real-estate development. In 1986, water use exceeded safe yield by about nine percent; and projected 1987 use is expected to exceed safe yield by about twelve percent. Although annual changes in water use are related to such variables as the weather and the economy, the continuing trend of increasing total water use has been due primarily to the construction of more houses, apartments, and businesses. As usual water use exceeds safe yield by greater amounts, water use must be reduced more frequently and by greater amounts to avoid running out.of water during periods of low rainfall. The city is seeking several supplemental water supplies which could be available by'the early 1990's, including conservation, drawing on Salinas and Whale Rock reservoirs in a way that would allow the combined safe yield to be slightly more than now estimated, using groundwater for landscape irrigation, and increasing the capacity of Salinas Dam. However, a major supplemental source of water, such as the coastal branch of the state aqueduct or a distribution system from Nacimiento Reservoir, probably will not be available until the mid to late 19901s. 36 If the city's usual water use did not exceed the safe yield, reductions from usual use would probably never be needed. However, when use exceeds safe yield, cutbacks from usual use may be needed to avoid running out of water. For example, when use exceeds safe yield by ten percent, the city would have to reduce consumption by five percent in about one out of eight years. About once in 25 years it would have to reduce consumption by five percent in one year and by ten percent in the following year. About once in 100 years the city would have to cut back during four consecutive years, about five percent in the first and increasing to about 23 percent in the fourth year. Alternatively, the city might be able to quickly develop temporary or permanent supplemental supplies, such as groundwater pumping, which could forestall the need for water -use cutbacks. These estimates are based on evaluations of rainfall records, the storage and refill characteristics of the reservoirs, and observed water -conservation behavior during droughts in San Luis Obispo and other communities. These estimates are derived from San Luis Obispo's 115 -year record of rainfall, including the six-year dry spell used to determine safe annual yield. A drought longer than six years may occur, though none has been experienced since 1869. Also, while the probability of a six-year drought appears small (once in 115 years), such a drought could begin any year. Less severe droughts are expected to occur more frequently. The following table shows how much and how often the city would have to reduce water use to avoid running out of water, if usual use exceeded safe yield by percentages ranges from five to 20. EXCEEDING THE SAFE YIELD - REQUIRED WATER -USE REDUCTIONS If usual water use exceeds safe annual yield by: 5% 10% 15% ' 20% About one year in eight, water use would have to be reduced: 5% 5% 5% 5% About once in 25 years, water use would have to be reduced two consecutive years and the maximum reduction in one year would have to be about: 5% 10% 15% 20% About once in 50 years, water use would have to be reduced three consecutive years and the maximum reduction in one year would have to be about: 10% 18% 25% 35% About once in 100 years, water use would have to be reduced four consecutive years and the maximum reduction in one year would have to be about: 10% 23% 34% 39% To minimize the risk of having to use less water than usual during droughts, the city would not exceed the safe annual yield. Or, it would have standby sources ready to use that would at least temporarily increase total safe yield. 37 A five percent reduction in water use can usually be achieved by making the public more aware of careful water use, through information efforts or increased rates. A 15 percent reduction would probably require mandatory conservation measures, such as watering only on certain days. A 25 percent reduction would require cutbacks in landscape watering and elimination of some water uses, such as washing cars. A 25 percent reduction is difficult to achieve and maintain. A 35 percent reduction approaches the levels met by northern California communities during the 1970's drought. This reduction could be achieved only by eliminating most landscape irrigation and imposing extra charges for water use over certain amounts. Reductions of 35 percent or more are very hard to achieve and nearly impossible to maintain for a long time without significant changes in peoples' behavior and in community character. Providing additional water supply and treatment capacity will lead to increased demands for other utilities. The city also collects and treats sewage through a system which is similar to the water system. The city has adopted a Sewer Service Plan (1980) which identifies a service area, service population, and relationship to water supply. (The city is updating the sewer service plan.) The service area boundary closely follows the urban reserve line of the general plan Land Use Element. The service area excludes the western Foothill Boulevard and - north Laguna Lake areas, which are potential locations for urban development if 6,000 acre-feet per year or more supplemental water is available. The sewage treatment plant can serve the equivalent of 50,824 people, according to the Sewer Service Plan. This number assumes average rates of use; the actual maximum population which could be served also depends on flows from nonresidential uses. Serving more people would require expansion of the sewage treatment plant. Therefore, supplemental water yielding more than about 3,500 acre-feet per year would support population levels requiring sewage -treatment plant expansion. The Sewer Service Plan notes that before annexation and development of major residential expansion areas or service -commercial expansion areas, supplemental water sources must actually be available. Electricity, natural gas, telephone, and cable television systems would be expanded to serve additional development. Utility companies say that so long as the expansion does not occur substantially faster than recently, they will be able to extend their lines and develop supporting systems to provide adequate service. Public Services Additional development enabled by additional water supply and treatment capacity would lead to increased demands for all government services. -Fire protection and paramedic services According to the City Fire Department, development of the named residential expansion areas would require three additional personnel to maintain the current level of service. Station 3 (Laurel Lane) and Station 4 (Madonna Road) would be most affected by the expected 21 percent increase in service calls. Development of the Orcutt expansion area would also affect Station 1 (Garden Street), since it sends six. people out of eight responding to a first alarm. The city has set four minutes as the maximum time for fire response to be effective. Station 1 personnel could respond to calls from the Orcutt area no sooner than six minutes. 38 Responding to medical emergency calls in the expansion areas will increase the chances that more than one call at a time will come to the nearest station, resulting in longer response times and the need to call on more distant personnel. The additional time taken by medical calls from the expansion areas is expected to decrease fire -prevention and training time by about five person -weeks per year. The Fire Department is particularly concerned about annexation of commercial areas (such as Sacramento Drive or the airport area) where development under county jurisdiction has not and probably will continue to not meet city fire -protection standards. Two existing businesses in the Sacramento Drive area alone would require a higher fire -flow delivery than on -duty personnel could provide. Alternatives for providing adequate fire protection include installing sprinklers in the annexed buildings or hiring more fire fighters. The expansion areas can be served from existing fire stations. -Traffic safety and crime services According to the Police Department, development of the named expansion areas would require additional personnel to provide current levels of service. As with fire response, the additional population would make multiple calls. or a single large incident more likely, diverting personnel from other calls. Gradual expansion would allow the city to provide adequate police services. -Public transit The city would have to expand its bus system to serve the development. enabled by proposed supplemental water. Route changes will be required. Some route changes are anticipated regardless of growth, as the street system changes. Additional busses may be needed to continue the city's level of service -- routes within one-quarter mile of most residents -- as residential areas expand. (The airport and the Edna -Islay area are not served now.) Present federal funding rules, which would entitle the city to more bus system subsidies after the population of the city and adjacent areas exceeds 50,000, are not likely to remain in effect. -Trash disposal A private company hauls trash from the city under a franchise. Trash is buried in a landfill several miles south of the city. According to the County -wide Solid Waste Management Plan (1977), this landfill has enough room to accept trash until about the year 2005, considering projected growth corresponding approximately with 5,100 -acre-feet per year of supplemental water. In the absence of significant resource -recovery or waste -reduction efforts, more people and businesses will need more space for trash disposal. -General government General government services include welfare, libraries, planning, development review, recreation, maintenance of streets and public buildings, civil and criminal justice, elections, and property records. Demands for all these services, provided by various city and county departments, will increase approximately in proportion to additional population and developed area. Recent experience indicates that most general government services can be expanded in pace with growth so long as the growth rate is moderate and sources of revenue are not changed suddenly. 39 -Schools For several years beginning in the 1970's, public school enrollment in the city declined, despite increasing city population, due to fewer school-age children per household and increasing enrollment in private schools. Two elementary schools and one of two junior high schools were closed. No new schools have been built since the 1960's. Enrollment in the early primary grades is increasing again, however, as the children of the "baby boom" generation enter school. Even without significant city population growth, enrollment will probably continue to increase for about five years. Even with growth, city-wide school capacity is expected to be adequate for the next ten to 15 years at least, though various grades will continue to experience fluctuating enrollments. However, the distribution of elementary students will not match school location if significant expansion occurs (Assessment of Future Development and Student Enrollment, Strong and Strong, January 1986). While school capacity would be adequate in the northern and central parts of the city, capacity in the southeast and southwest areas would not be. Development of the Edna -Islay and Orcutt expansion areas would exceed the capacity of Sinsheimer and Los Ranchos elementary schools. Development of the Irish Hills and Dalidio expansion areas would exceed the capacity of C.L. Smith School. Use of portable classrooms and having students attend schools outside their neighborhoods can delay the need for new school sites, but not the need for more staff than would be required with less city growth. 40 ENVIRONMENTAL IMPACTS OF WATER PROJECTS The following summary tells how development of alternative water sources would impact project settings. In some cases, more detailed study is required to describe the impacts and risks of various projects. This summary can help set the scope for future studies. The no -project and conservation -only alternatives would avoid these impacts. Proiect Raise Salinas Dam spillway (enlarge Santa Margarita Lake) Additional land area covered by water in reservoir: 320 acres Type of land changed to lake: oak grassland; Variations in lake level: up to 18 feet deeper Downstream flows: no dry -weather change; reduced flood flows Areas flooded if dam fails: slightly more than with present dam Risk of dam failure: unknown Miles of transmission pipe: existing pipe would be used Type of land affected by transmission route: no new impacts Energy used/produced in water transmission: minor net energy production Project Santa Rita reservoir (new lake) Additional land area covered by water in reservoir: unknown Type of land changed to lake: oak grassland and chaparral Variations in lake level: unknown Downstream flows: reduced flood flows Areas flooded if dam fails: Santa Rita Creek, Paso Robles Creek, and the Salinas River floodplain immediately upstream from Templeton. Risk of dam failure: unknown Miles of transmission pipe: unknown Type of land affected by transmission route: unknown Energy used/produced in water transmission: unknown 41 Proiect: County Water Plan alternatives using Nacimiento and/or state water project only Additional land area covered by water in reservoir: none within county Type of land changed to lake: None Variations in lake level: None at Nacimiento, except in extreme droughts Downstream flows: reduced Areas flooded if dam fails: no change from current conditions Risk of dam failure: unknown Miles of transmission pipe: varies with specific project Type of land affected by transmission route: pasture, oak grassland, oak woodland, chaparral Energy used/produced in water transmission: varies with specific project; probably net consumption Proiect: Jack Creek reservoir (new lake which would be a part of some of the county water plan alternatives) Additional land area covered by water in reservoir: unknown Type of land changed to lake: oak woodland, chaparral Variations in lake level: unknown Downstream flows: reduced flood flows Areas flooded if dam fails: Jack Creek, Paso Robles Creek, and the Salinas River immediately south of Templeton Risk of dam failure: unknown Miles of transmission pipe: unknown Type of land affected by transmission route: unknown Energy used/produced in water transmission: unknown 42 Pro' Cooperative use of Salinas and Whale Rock reservoirs Additional land area covered by water in reservoir: 0 acres Type of land changed to lake: None Variations in lake level: less than now in Whale Rock and more at Salinas Downstream flows: Salinas dam would spill less frequently, Whale Rock more frequently than now Areas flooded if dam fails: no change from current Risk of dam failure: no change from current Miles of transmission pipe: none Type of land affected by transmission route: no new impacts Energy used/produced in water transmission: no significant change from current Proiect: Cantera Reservoir (new lake) Additional land area covered by water in reservoir: unknown Type of land changed to lake: oak grassland, chaparral Variations in lake level: unknown Downstream flows: reduced flood flows Areas flooded if dam fails: Salinas River floodplain north of Santa Margarita Risk of dam failure: unknown Miles of transmission pipe: unknown Type of land affected by transmission route: unknown Energy used/produced in water transmission: unknown 43 Pro'ec : Salinas Reservoir conjunctive use (groundwater storage) Additional land area covered by water in reservoir: none Type of land changed to lake: none Variations in lake level: greater than now Downstream flows: reduced flood flows Areas flooded if dam fails: same or less than now Risk of dam failure: none Miles of transmission pipe: unknown Type of land affected by transmission route: grassland, riparian plain Energy used/produced in water transmission: unknown Proiec : Waste water reclamation Additional land area covered by water in reservoir: 0 acres Type of land changed to lake: None Variations in lake level: Not applicable Downstream flows: Reduced dry -season flows Areas flooded if dam fails: Not applicable Risk of dam failure: Not applicable Miles of transmission pipe: up to 2 miles Type of land affected by transmission route: Agricultural, streets, residential Energy used/produced in water transmission: some energy used 44 ENVIRONMENTAL IMPACTS OF TREATMENT AND DISTRIBUTION SYSTEM CHANGES The water treatment plant can be modified and expanded without causing significant impacts. Nearly all the proposed changes to pipes, valves, and tanks can be made without lasting impacts. Some noise, air, and water pollution will be caused by construction, but the environment will generally return to its pre -project condition. Impacts from the water:system changes to support expansion of the city have been described above. These changes would follow from a choice of supplemental water, and would not occur independently. Construction of a new water tank in the vicinity of General Hospital will cause visual impacts, since it will probably be located on a hillside above Johnson Avenue. Both the tank itself and an access road are likely to change the appearance of a natural area. Since a precise location has not been proposed, more specific conclusions cannot be made. When a proposal is made, an initial environmental study will describe impacts and mitigation measures. MITIGATION MEASURES Mitigation measures, according to state environmental guidelines, are those features of a project which will reduce undesirable effects to acceptable levels. EIR's are to distinguish between mitigation measures recommended by the EIR and those actually incorporated in project approval. Obtaining major supplemental water supplies will have several adverse effects on the environment. However, the Water Management Element and the Water Management Plan was not intended to and in most cases realistically cannot include mitigation measures. Depending on -the type of impact, mitigation measures may be unavailable, already incorporated in city plans and projects unrelated to water resources development, or the responsibility of other agencies. The following outline describes mitigation measures for various types of impacts. For those growth impacts where mitigation measures are included in other city plans or the responsibility of other agencies, more growth will make the impacts more severe regardless of mitigation. In these cases, mitigation is not truly a measure related to water resources development. IMPACT: Population growth and resulting land -use changes. MITIGATION: Recommended in draft EIR: Amend the general plan Land Use Element to require phased development of the expansion areas, consistent with Housing Element policy favoring those with the best proposal for affordable housing. Specific plans would state the earliest date when development of an area or phase could begin. 45 Included in council action (final EIR): The recommended action (to be considered during Land Use Element revision proposed for 1987-88). Already included in other city plans or actions: Residential Growth Management Regulations limit increases in the housing stock to about two percent annually during the 1980's and one percent annually during the 1990's (expire end of 1999). General plan Land Use Element requires a specific plan for each expansion area. Responsibility of other agencies: None. IMPACT: Traffic increases and resulting noise and air pollution. MITIGATION: Recommended in draft EIR: Amend the general plan Land Use Element to include a policy relating growth and air quality, such as: "The city hopes to at least maintain air quality levels experienced during 1980 through 1985. The city will periodically evaluate air quality information provided by the County Air Pollution Control District and the state Air Resources Board. Development of major expansion areas will be allowed only if air pollution is kept within State and Federal standards." In addition, the city should try to persuade all agencies in the county to approve major developments only when they can show that air pollution from existing sources will be reduced to offset the pollution added by the development. Included in council action (final EIR): The recommended action (to be considered during Land Use Element revision proposed for 1987-88). Already included in other city plans or actions: City operates a bus system. City maintains bicycle lanes and provides them along new or rebuilt major streets. City encourages city -employee car-pooling and bus ridership. General plan Circulation Element and budget include street projects to reduce traffic delays. City reviews projects along major roadways and administers state building code standards for noise protection. 46 Responsibility of other agencies: Traffic management Government partnerships operate regional bus system. County coordinates ride -sharing program. Air Quality Noise Federal and state governments set acceptable pollution exposure limits. Federal and state governments set mobile and stationary pollution -source standards. State and county enforce pollution -production limits. Federal and state governments set acceptable noise -exposure limits. State government sets vehicle -noise standards. IMPACT: Drainage and Flooding MITIGATION Recommended in draft EIR: None Included in council action (final EIR): None Already included in other city plans or actions: Flood Damage Prevention Regulations require new buildings to be flood -proof and to minimize changes to flood levels and locations. Flood Management Plan attempts to delay peak flood flows in small streams and accommodate them in large streams, without destroying wildlife habitat and esthetic appeal of natural creeks. Responsibility of other agencies: County flood regulations apply to construction downstream from San Luis Obispo. 47 IMPACT: Water Quality MITIGATION: Recommended in draft EIR: None Included in council action (final EIR): None, but Sewer Service Plan to be updated. Already included in other city plans or actions: Developments along creeks are often required to post signs concerning creek pollution. Projects with large parking lots near creeks are often required to provide sumps that separate some oil from water at low flows. City requires erosion control during grading and construction. Responsibility of other agencies: State Water Quality Control Board, through a regional board, sets and enforces standards for discharges to creeks from such sources as sewage treatment plants and businesses, but not from construction sites or street and yard drainage. State Department of Fish and Game reviews major creekside projects and investigates spills. IMPACT: Aesthetics MITIGATION: Recommended in draft EIR: None in addition to those measures recommended to reduce growth effects and slow the apparent pace of change. Included in council action (final EIR): No additional measures. Already included in other city plans or actions: The Architectural Review Commission approves new commercial and multi -family residential projects and tracts where houses will be built in groups of three or more. The general plan Land Use Element requires specific plans for expansion areas. The specific plans may set aside space for preservation of natural features. Responsibility of other agencies: County government regulates land -use outside the city limits. 48 IMPACT: Dam Failure MITIGATION: Recommended in draft EIR: None Included in council action (final EIR): No additional actions, but staff directed to begin seismic safety study for enlarging Salinas Dam. Already included in other city plans or actions: Inspection of Whale Rock Dam. Responsibility of other agencies: U.S. Army Corps of Engineers and S.L.O. County inspect Salinas Dam. If the city develops dams on its own or in partnership with other agencies, the dam owners would be responsible for design, construction, and inspection, in conformance with state requirements. IMPACT: Disruption by dam -to -city pipes , MITIGATION: Recommended in draft EIR: Following existing road and utility rights-of-way where feasible. Included in council action (final EIR): The recommended action. Already- included in other city plans or actions: None Responsibility of other agencies: None 49 1 ENVIRONMENTALLY SUPERIOR ALTERNATIVE State environmental rules require the city to describe and evaluate a range of reasonable alternatives. If the environmentally superior alternative is "no -project," the city must then identify which other alternative is environmentally superior. The conservation -only alternative, followed closely by cooperative -use -only alternative would cause the least harm to the environment. These supplemental water sources are the environmentally superior choices. SHORT-TERM USE AND LONG-TERM PRODUCTIVITY According to state environmental rules, an EIR for a plan must also discuss the relationship between short-term decisions and long-term effects, including reasons why the project is justified now (Guidelines Section 15126). The city's water choice will affect how many more people can live in the city and how far out it can expand, including all theeffects of urban growth. The City Council is considering the Water Management Plan because additional water is necessary if the city is to continue to grow. The council knows that choices of additional water sources must be made now if the growth is to continue with little interruption, since designing and building a dam or pipes will require several years. Other agencies in the county face similar choices, prompting the city to consider being part of a county -wide water decision. Some city residents believe that the qualities of the natural environmental which would be lost in accommodating growth can not be adequately compensated by additional city revenue or financial benefits. CUMULATIVE IMPACTS The city must also consider cumulative impacts -- the combined effects of similar projects. As noted before, other agencies in the county face similar water limits and are considering ways to overcome them. The cumulative impact of all agencies obtaining supplemental water will be continued county -wide development: less open space and more people, with more vehicles, and all the resulting effects. Throughout California, as cities grow and as the open lands between are developed, fewer communities offer the type of setting enjoyed by San Luis Obispo. Communities along major highways such as Highway 101 are particularly vulnerable to this trend. If a substantial amount of additional water is available throughout the county, four urban areas will form with one and one-half to two times their current populations: the "Five Cities" area from Oceano to Shell Beach; the Estero Bay area from Baywood-Los Osos to Cayucos; the Salinas Valley area from Santa Margarita to Paso Robles; and the San Luis Obispo area, from Los Ranchos to Cuesta College. IRREVERSIBLE IMPACTS Adoption of the Water Management Element itself is not an irreversible decision. It may be repealed or amended at any time. The Water Management Plan would be a more definite step in carrying out supplemental water projects. Authorization of specific projects, particularly those involving other agencies, is largely irreversible once design and financing commitments have been made. Actually securing supplemental water would be irreversible. 51 Choosing to not seek a major source of supplemental water would be a reversible decision, since the choice to seek water could be made in the future. Choosing to not pursue any particular source would leave open the option of pursuing most other sources. Choosing one particular source would not. necessarily commit the city to securing or not securing other sources, though the city is not likely to pursue more than one major water project at a time due to cost. If the city does not participate in the State Water Project but the county does, the city may lose its tentative commitment to water from that source. If the county does not participate, the county and the city may loose their entitlements. (The water rights could be sold to agencies which want the water, such as San Joaquin Valley irrigators or Southern California cities.) Urbanization of land enabled by supplemental water would be an irreversible effect. Traffic, air pollution, and noise effects are also largely irreversible. Significantly higher fuel costs or fuel shortages, or significantly more effective state or federal standards for air or noise pollution, which would avoid or reduce these impacts, are not likely to change during the term of the water management Plan (1986 through 2020). However, motor fuel availability will probably change significantly after this period. Loss of agricultural land and other open space would be irreversible. Most of the energy and materials used to construct and operate systems to provide water could not be recovered. 610A T -- STATUS OF IMPACTS State environmental rules require the city to determine which types of impacts could be significant. (Guidelines Section 15126). The city must then name those which will be avoided or reduced to insignificant levels through features incorporated into the plan. The city must also explain overriding reasons for approving a project with significant impacts that cannot be avoided (Guidelines Sections 15091-15093). The following outline describes the status of each type of impact as determined by the City Council in the final EIR. Insignificant: Community Plans and Goals Geologic Changes and Hazards Plant Life Animal Life Energy Potentially Significant; will be acceptable with recommended mitigations Noise Air Pollution Public Services & Utilities Drainage and Flooding Water Quality Historical and Architectural Resources Traffic Significant; mitigation unavailable or inadequate (overriding concerns justify project): Population Growth Land -use changes Aesthetics OVERRIDING CONCERNS In adopting the Water Management Element, the City Council identified these reasons for carrying out the project despite significant, unavoidable impacts: provision of adequate water for growth which may occur in conformance with the Land Use Element and for affordable housing as provided in the Housing Elcment; diversion of some growth from other places in the region that could accommodate it but with more severe impacts; expansion of the city to better control the type of development which might occur at its edges. 53 ORGANIZATIONS AND PERSONS CONSULTED c The following people provided information for or commented on drafts of this report. Copies of all written comments on the draft EIR, records of public hearings, and responses to significant issue raised are on file in the City of San Luis Obispo Community Development Department. Paul Allen, Robert Carr, Terry Dressler, S.L.O. County Air Pollution Control District Melanie Billig, San Luis Obispo League of Women Voters Suzanne Butterfield, California Department of Water Resources Mike Dolder, City of San Luis Obispo Fire Chief Hal Fones, City of San Luis Obispo Utilities Engineer Gary Henderson, City of San Luis Obispo Engineering Division Bill Hetland, City of San Luis Obispo Utilities Manager Nancy Knoffler, City of San Luis Obispo Transit Manager Barbara Lynch, City of San Luis Obispo Traffic Engineer Clint Milne, County of San Luis Obispo Deputy Engineer Vic Montgomery, planning consultant Jack C. Parnell; California Department of Fish and Game Wayne Peterson, City of San Luis Obispo City Engineer Ellen Rognas, County Environmental Coordinator Dave Romero, City of San Luis Obispo Public Works Director San Luis Obispo City Council members (listed in Water Management Element) San Luis Obispo City Planning Commission members (listed in Water Management Element) Martha Schwartz, San Luis Obispo League of Women Voters Steve Seybold, City of San Luis Obispo Crime Prevention Officer Don Smith, resident of San Luis Obispo PREPARATION This report was prepared by staff of the City of San Luis Obispo Community Development Department, including: Toby Ross, acting city administrator and former director Michael Multari, director Glen Matteson, associate planner Glenda Murray, word processing Allen Hopkins, administrative services Rick Hocker, graphic services IN 54