HomeMy WebLinkAbout03/12/2002, SS 2 - CITY OF SAN LUIS OBISPO WASTEWATER MASTER PLAN CAO RECOMMENDATION j.
council M Dale
Maa rch 12 2002
acenaa nepoat 2
CITY OF SAN LUIS OBISPO
FROM: John Moss,Utilities Direc114(r_'
Prepared By: David Hix,Wastewater Division Manager
SUBJECT: CITY OF SAN LUIS OBISPO WASTEWATER MASTER PLAN
CAO RECOMMENDATION
Receive and file the report and consider specific projects as they come forward in future financial
plans.
REPORT-IN-BRIEF
The City selected Brown and Caldwell engineers to prepare a Wastewater Master Plan in concert
with the Airport Area Specific Plan and Environmental Impact Report (EIR). The Master Plan
analyzed the City's existing facilities, processes, and makes recommendations for improvements
that will be needed to accommodate growth and build out per the City's General Plan. The Master
Plan recommends wastewater collection systems improvements for the replacement and/or upgrade
of the Tank Farm, Howard Johnson and Silver City Lift Stations. Anticipated growth will require
the expansion of processes at the Water Reclamation Facility (WRF) to meet capacity by 2010..
These recommendations address both capacity and operational/maintenance issues and should
provide adequate wastewater infrastructure for conformance to the City's General Plan.
DISCUSSION
Several years ago the City released a request for proposal (RFP) for consultant services for the
Airport Area Specific Plan, environmental impact report and related facilities master planning. The
scope of work called for a City wide wastewater master plan that would analyze and evaluate the
existing operations of the Water Reclamation Facility (WRF) and wastewater collection system as
well as future demands that these facilities face to meet build out based on the City's General Plan.
The document is intended to provide a long-range plan to guide implementation of recommended
improvements and expansion of services to future expansion areas.
The City selected Brown and Caldwell Engineers to prepare the Wastewater Master Plan. Brown
and Caldwell had prepared the City's last wastewater management plan in 1987 and provided
design services for the latest WRF upgrade, belt filter press and Laguna Lift Station. Brown and
Caldwell met with City staff, visited facilities and reviewed reports to determine then analyze where
improvements will need to be made and what facilities will need to be added or enlarged to
accommodate new annexation areas and build out of the City-wide wastewater system.
Below is a detailed summary of the major components and projects of the wastewater master plan,
schedules and costs.
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C) 'C
Council Agenda Report-Title of Report
Page 2
Wastewater Collection System Overview
The City's existing wastewater collection system is comprised of approximately 130 miles of
mainline pipe that range in size from 6 to 48 inches. The majority of the pipe is vitrified clay with
concrete mortar joints. Over half of the system is 6-inch pipe. Most of the collection system was
constructed prior to 1960 with some pipe dating to the tum of the last century.
In areas of the City where adequate grade could not be achieved, sewage lift stations have been
installed to pump wastewater to areas of the system where gravity can again be used to move
wastewater. Currently the City operates and maintains 8 lift stations, all of which are at or near their
life expectancy, lack permanent emergency power and require a confined space entry for
maintenance activities. Several of the lift stations are over capacity and one, Rock View lift station,
experiences operational problems because of its configuration.
Pump Stations and-Force Mains
Master Plan Recommendations
The wastewater master plan recommends upgrades to several of the City's lift stations. The
majority of these improvements are in the Southern portion of the City to accommodate future
growth, capacity, and operations and maintenance issues with the existing lift stations. All of the
City's current lift stations are below ground "can" type stations that require a confined space entry
permit for maintenance and have no on site backup power.
The master plan recommendations for the lift stations that require upgrading address the capacity,
operations, maintenance and emergency power issues. Figure 1 shows the location of the lift
stations discussed in this report. Below is a summation of the recommendations for specific lift
station improvements and upgrades identified in the master plan.
Laguna Lift Station and Force Main
Construction of the new Laguna Lift Station and force main are nearing completion. This lift
station handles approximately one quarter to one third of the City's wastewater, has two other lift
stations that discharge to it and serves the Madonna/Los Osos Valley Road, western portion of the
airport area and,Lower Higuera area. The Laguna Lift Station was identified for replacement in the
City's 1987 Wastewater Management Plan. The new lift station will provide adequate capacity for
future development, have backup emergency power, will not require a confined space entry for
maintenance and will require significantly less maintenance. The lift station's Asbestos/Concrete
(AC) force main has also been replaced to accommodate future capacity and eliminate maintenance
problems. Design and construction began in 2000 and is nearing completion, delivery of the
pumping equipment and testing have caused delays. This lift station is expected to be completed
and brought into service by fall of 2002.
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Council Agenda Report- Title of Report
Page 3
Tank Farm Lift Station and Force Main
Tank Farm Lift station was installed in 1966, is well past its intended service life and is at or over
capacity. This lift station currently receives flows from the Edna Islay and airport area and will
receive significant additional flow from the Airport, Margarita and Orcutt areas. Tank Farm lift
actually pumps to another lift station, Rock View, which then pumps all the wastewater to a gravity
main. This pumping arrangement has caused operational problems including overflows and is
inefficient.
The master plan recommends the replacement and relocation of this lift station to a site
approximately one mile West on Tank Farm Road from its current location at the corner of Tank
Farm and Broad Street. This project also includes the installation of a new gravity line down Broad
Street and Tank Farm to the new lift station site, and a new force main to connect at Prado Road.
Installation of the new gravity lines will allow the retirement of the existing Rock View and the
Airport Lift Stations.
Total estimated cost of this project is $5,000,000. Funding for the design of this project has been
identified as$500,000 in the 1999-01 budget,while construction costs of$4,500,000 were identified
in the 2001-03 Financial Plan as a 2003-04 capital project. Staff requested this funding using
information from the draft Master Plan because of the urgent nature of the identified capacity,
operational and maintenance problems and the need to replace this lift station even if the proposed
annexations do not immediately take place.
Howard Johnson Lift Station
Howard Johnson lift station receives wastewater from the South Higuera Street and Auto Parkway
areas and pumps to the Laguna Lift Station. This lift station was installed in 1967 and is past its
expected service life. It has also flooded several times which has left the wiring in poor shape and
control panels badly corroded.
This lift station is recommended for upgrading to both meet the expected future flows and because it
is due for replacement. Replacement of this station is recommended when future flows near
capacity. Staff estimates this to be 2005-06 and is estimated to cost $900,000, design should begin
in 2004-05 and construction of this project should be completed in 2005-06.
Silver City Lift Station
This lift station currently serves the Higuera Street area South of Prado and North of Tank Fane
Road and pumps to the Laguna Lift Station. This lift station will take some of the flow from the
Margarita area and will require its pumps and controllers to be upgraded when flows near capacity.
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Council Agenda Report-Title of Report
Page 4
Margarita Lift Station
This lift station receives wastewater from the Margarita Avenue area and will receive wastewater
from a portion of the Margarita annexation area when it is annexed. Adequate capacity currently
exists in the lift station and no upgrades to its pumps or controllers will be required.
Madonna Lift Station
The master plan recommends that this lift station and its operation and maintenance be transferred
to the owner of the Madonna Inn because it only serves that property. If Council should adopt this
recommendation, staff will have to negotiate the transfer with the Inn's owner.
Rock View
This lift station is recommended to be deactivated when the proposed new Tank Farm lift station
becomes operational. Rockview currently receives almost all of its flow from Tank Farm Lift
Station that results in operational and maintenance problems and has caused overflows. The small
amount of gravity flow to Rock View Lift will be directed to the proposed new Tank Farm lift
station via a new gravity line in Broad Street.
Airport
This lift station currently receives flow from the airport area South of El Capitan on Broad Street
and pumps to the Tank Farm Lift Station. The Airport Lift Station will also be deactivated with the
installation of the proposed new Tank Fane Lift Station, which will be deep enough to take flows
from this service area,by gravity.
Summary of Recommended Collection System Improvements, Costs and Completion Dates
Project including study,design and construction Cost Completion Date
Tank Farm Lift Station and Force Main and abandonment of $5,000,000 2003-05
old Tank Farm,Rockview and Airport Lift Stations.
Howard Johnson Lift Station $900,000 2005-06
Silver City Lift Station $180,000 2007-09
Main Lines
Current Status
The City's 1987 wastewater management plan recommended the installation of a relief sewer
interceptor from Montalban at Hathaway to the WRF to alleviate overflows, reduce the amount of
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Council Agenda Report-Title of Report
Page 5
parallel sewers and decrease maintenance. Since the completion of the interceptor and several other
major sewer improvements, plus the ongoing replacement of mainlines around the City, overall
system capacity is currently considered adequate.
Inflow and Infiltration (1/1) continue to be a problem for the collection system. Ongoing
replacement of the City's mainlines plus the lateral rehabilitation program should begin to slowly
reduce UI over the coming years. Participation from City residents in the lateral program has been
excellent and over 330 laterals have been partially or fully replaced. City staff will be bringing
recommended changes to the program this spring. The master plan also recommends further
evaluation of the effectiveness of the City's N program.
Master Plan Recommendations
A trunk system of gravity lines needed to serve the expansion areas will be the responsibility of the
City to install. The City will also install a"feeder"gravity line to connect a portion of the Margarita
area to the proposed new Tank Farm line. Figure 2 shows the recommended backbone sewer
installation, recommended in the master plan. Mainline installation to connect to this trunk system
for individual development areas will occur with the development and be the responsibility of the
developer.
Water Reclamation Facility
Current Status
The City's Water Reclamation Facility (WRF) was last upgraded in 1994. This project added
nitrification by aeration, clarification, equalization, cooling, filtration and
disinfection/dechlorination processes to provide the City a full tertiary facility. Currently the WRF
has all the necessary facilities to treat wastewater to current regulatory standards for discharge to
San Luis Obispo Creek. This may change because of pending regulations regarding nutrients,
trihalomethanes, State regulations for effluent dependent water bodies, the Municipal/Domestic
drinking water beneficial use identified for San Luis Obispo Creek and the City's pending National
Pollutant Discharge Elimination System (NPDES) permit. Changes in these requirements may
necessitate additional Master planning and construction of treatment processes to comply with these
new regulations. These requirements were not addressed in this master plan because they are still
pending, have just recently been introduced and/or continue to be negotiated with the Regional and
State Water Boards. Staff will continue to analyze, evaluate and comment on these pending
regulations and provide Council recommendations for compliance.
Master Plan Recommendations
Currently the WRF's average dry weather flow is 4.5 million gallons per day (MGD) with a
maximum treatment capacity of 5.1 MGD. Per current regulations, to treat the increased flow from
the proposed annexation areas and serve build out per the City's General Plan, the WRF will require
the addition of a cooling tower and cooling tower effluent pump, a dual media filter and filter
effluent pump, another chlorine contact tank and Dissolved Aeration Flotation Tank (DAFT).
Z� S
Council Agenda Report-Title of Report
Page 6
These improvements will need to be constructed when the City's population starts to approach
50,000 and the WRF begins nearing maximum capacity, estimated to be approximately 2008.
Total estimated costs for study, design and expansion of the WRF have been estimated to be
$4,300,000. Funding for study and design of this project have been identified in the City's 2001-03
financial plan, appendix B, as $100,000 for study in 2002-03 and$1,000,000 for design in 2004-05.
Construction of the recommended expansion is estimated to begin in 2006-07 and cost$3,200,000.
The master plan also recommends several capital improvement maintenance projects with assigned
priorities. Two of these projects, the boiler and potable water air gap, are currently in the WRF's
major facility maintenance and upgrade capital improvement requests for the 1999-01 and 2001-03
financial plans. The City's energy services consultant for possible cogeneration opportunities is
currently reviewing the boiler replacement project. The remainder of these projects and an
evaluation of the entire facility's processes will be evaluated during the study portion of the WRF's
required improvements.
Summary of Recommended WRF Improvements,Costs and Completion Dates
Project including study, design and construction Cost Completion Date
Stud $100,000 2002-03
Design $1,000,000 2004-05
Filter,Cooling Tower,Disinfection and DAFT $3,200,000 2006-09
FISCAL IMPACT
There is no immediate fiscal impact associated with this report and the recommended action. Some
of the recommended improvements for near term projects such as the design and construction of the
Tank Farm Lift project and the study and design phase of the WRF's Master plan implementation
have been placed in the current Financial Plan's capital improvement planning, and have been made
part of Sewer Fund analysis and rate forecasts. This was done because of the urgent need to replace
Tank Farm Lift Station and the time frame that is necessary to study and design improvements at
the WRF. Staff will not request direct funding for these projects until Council has considered the
Airport Area Specific Plan and EIR. The improvements necessary to serve new development will
be incorporated into the Sewer Impact Fees for new development and are being provided to Council
in a separate report at this study session.
Figure 1. Map of Wastewater Lift Stations
Figure 2. Backbone Sewer and Water Improvements
* Full copy of the Wastewater Master Plan is in the Council reading file.
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