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HomeMy WebLinkAbout12/04/2001, 2 - SAN LUIS OBISPO PHASE II WATERWAY MANAGEMENT PLAN council j acEnbA REpoRt CITY OF SAN LUIS OBISPO FROM: Mike McCluskey,Public Works Director SUBJECT: SAN LUIS OBISPO PHASE II WATERWAY MANAGEMENT PLAN CAO RECOMMENDATION: 1. Receive a presentation on the draft San Luis Obispo Phase H Waterway Management Plan. 2. Provide direction to staff on any changes to the proposed Plan in the areas relating directly to the City of San Luis Obispo. 3.. Give feedback and comments on areas of the proposed Plan relating to locations outside the City of San Luis Obispo. DISCUSSION Background and Status of the San Luis Obispo Phase II Waterway Management Plan A. Floods of 1969 and 1973 These two storms awakened the community to the problem of flooding along the San Luis Obispo creek system. During the post-war growth years the City had not experienced any serious flooding problems and had not performed any significant maintenance of the major creek system. The immediate response to the 1973 flood was the formation of Zone 9 of the County Flood Control and Water Conservation District. This Zone of Benefit included the entire San Luis Obispo Creek Watershed. It was formed with a primary responsibility to gather information about flooding and to develop a plan to reduce or eliminate flood impacts. Funding was also to be provided for minor maintenance of the waterway. Capital improvements were not to be funded by the original tax levels. Originally, a .08% tax rate was established that was to be reduced to .05% after five years. The approval of Proposition 13 froze the tax formula and resulted in a continuing flow of tax dollars into the program. In the years since its formation, Zone 9 has funded the Nolte Study of 1977, which recommended standards and projects to reduce flooding. The recommended projects were a basis for the City's 1983 Flood Management Policy (Pink Book). Funds in the County program were used each year to pay for clearing major creeks and the repair of creek banks damaged by high flows in areas under public control. Generally, funds for projects in the City and in the County were divided, with 80% going to the City, since it represented about 80% of the funding source. Over time, the balance in the Zone 9 fund has increased. After the 1995 storms, the City was able to fund a major portion of a creek bank repair program from the Zone 9 balance and Zone 9 funds were budgeted to pay for the Questa Phase I and II studies being discussed at this meeting. BUS 2-1 f r Council Agenda Report-Waterway Management Plan -Phase II Page 2 B. Pink Book Flood Management Policy—Adopted by Council June 1983 This document included policy information on design and construction standards for waterways, storm drains and drop inlets, and listed a number of projects of varying scale to address points of restriction to flood flows, as well as minor and major creek projects to increase capacity. Many of the projects proposed were completed, with the main exception being the $20.5 million in Major Waterway Modifications. Council funded some of the major projects, but ultimately declined to approve final plans and specifications because of costs and environmental concerns. C. 1995 Floods The 1995 floods once again reminded the City of the flooding and bank instability problems along the San Luis Obispo Creek. At that time, the Council had already adopted a goal to review and update the "Pink Book'. Staff reductions of 1993, and permitting and environmental issues related to flooding that occurred in 1995,prevented staff from accomplishing this goal. In the summer of 1995, staff's application to the Army Corps of Engineers for permits to perform flood damage repairs raised several "cumulative effects" and "downstream impacts" issues that led to the Corps's requirement to perform comprehensive engineering and environmental studies of the entire water shed. These studies revisited the Nolte Study and are now the basis for proposed new City policies on Flood Plain Management and revised design standards for drainage,bank stabilization, and flood control in the City. In the fall of 1995, the Corps asserted discretionary authority over bank stabilization measures within the San Luis Obispo Creek and its tributaries. The Corps' response to the City's permit application was outlined in a letter dated April 30, 1996. It determined that each additional project that would channelize or otherwise affect the creek would result in greater than minimal cumulative impacts and require an individual permit (a costly and lengthy process). Instead, the Corps recommended that the City submit a single individual permit application for a comprehensive, long-term drainage plan for the creek. The process was initiated with a Request for Proposals for a two-part study. The study was broken into two parts because the City and Corps recognized in 1996 that the City needed to repair certain high priority creek banks damaged in 1995 and that the entire study required by the Corps would take some time. The first phase was an abbreviated study approved by the Corps that covered only portions of the creek where permits for bank repair were needed immediately. The Phase II portion of the study covers the entire San Luis Obispo creek and its major tributaries, and will satisfy the Corp requirement for a comprehensive long-term drainage plan. Questa Engineering was selected for both phases of the project following established City procedures. D. Annroval of Phase II Contract- 1999 Phase II of the study was approved to begin in late fall of 1999. It also had two parts. The first was an aerial survey of the major creek system from the base of Cuesta Grade to the ocean. The second was an engineering and environmental technical study. Information from the first sub- BUS 2-2 Council Agenda Report=Waterway Management Plan-Phase II ' Page 3 part was necessary before any real progress could occur on the second, since the information was needed for development of new computer and hydrology models. The City expanded the scope of the aerial work to include the entire City Urban Reserve Area. The aerial work utilized LIDAR technology to determine elevation contours. This was an efficient way to obtain solid information and avoid as much manual surveying as possible. Unfortunately LIDAR technology is a very advanced form of survey with few vendors in the country. The initial vendor was unable to perform due to equipment failure; therefore, another vendor was brought in. The second vendor also had some difficulty, resulting in additional delays in completion of the initial work. Another delay in the project occurred when the County, because of a pending lawsuit, withheld data from our consultant because another consultant owned it. Our consultant delayed pursuing alternate methods of obtaining this data because the County told him that their data would be available shortly. The County's data was significantly superior to any alternative data our consultant could obtain and waiting made good sense. The original schedule showed the project starting in November 1999 with completion in January 2002. At this time, the project is nearly a year behind schedule, with completion of all the work now projected for fall 2002. Completed Phase II Waterway Management Plan Tasks 1) Aerial photo and topography contour maps: The City and County have an excellent photo of the waterway from the base of Cuesta Grade to Avila including See Canyon. The photo is in color and has an extremely high resolution. There is also a topographic contour map with %i meter contours of the waterway. Similar maps are in the City's possession for the entire Urban Reserve area. 2) Watershed reconnaissance, inventory, hydrology and geomorphology: The raw data is in the City and County's possession and is displayed for the public on a web site maintained by Cal Poly. It will be included as appendices to the overall plan. 3) Computer Models: The hydrology and hydraulic models have been completed using standard Corps of Engineers procedures. 4) Sediment Study: A special study was conducted following 2-dimensional modeling of sediment transport problems at the Marsh Street Bridge and is completed. 5) Problem Identification: Two meetings were held with the public to discuss problems and to identify missed issues. Solutions to problems were identified and are included in a document. Status of the Phase II Waterway Management Plan Documents The following documents have been received and reviewed. Final versions are still forthcoming except as noted. BUS 2-3 Council Agenda Report—Waterway Management Plan-Phase II Page 4 1) Design Manual — Draft submitted. Currently undergoing additional edits. To be delivered December 4, 2001. 2) Flood Elimination Plans — Three alternatives with costs completed. Alternatives to be presented to Council on December 4, 2001. 3) Maintenance Plan — Completed. Now termed "Stream Maintenance and Management Program. 4) Mid Higuera Flood Plan: - Final Document received and used by Community Development in the presentation of the Mid Higuera Street Plan. 5) Stream Bank Stabilization Handbook—Completed; now a chapter in design manual 6) NPDES Plan for San Luis Obispo. Final Document received and accepted by Council. 7) EHZIEIS—Early stages; this piece of major work should be completed by April 2002. The draft Waterway Management Plan Phase H brings all of the aforementioned tasks and documents, except the EIR, into one summary plan document. The final document is scheduled for completion in mid-December, based on Council direction at this study session. This document will then be circulated for agency comments in.January 2002. The Plan is well over 300 pages long. Therefore, it will not be placed in the Council reading file. After the Study Session, if any council member would like to be more thoroughly briefed on any one section or have their own copy of the document, staff will arrange to meet that request. Areas for Discussion and Council Feedback 1) Design Manual - the Consultant will overview the following areas that will determine how the City designs future improvements: a) Design storm levels b) No net fill concept and special zones C) Possible Drainage Impact Fee d) Possible channel conveyance design capacities for each reach (differs for each reach and will be dependent on alternative selected) 2) Stream Management Program - the consultant will provide a brief review of the following elements and seek Council comments and possible direction: a) Current permit situation b) Proposed permit streamlining c) Vegetation management d) Bank stabilization procedures 3) Flood Management Plan a) Comparison of FEMA and Zone 9 model flows and Flood Zone Problems b) Alternatives and their costs BUS 2-4 Council Agenda Report=Waterwaygement Plan-Phase H Page 5 C) Bank stabilization program FISCAL IMPACT During this study session staff will review many variables. Depending on feedback from the Council, the costs of implementation will vary. However, staff is independently working on the establishment of a Storm Water Utility that will most likely fund most of the improvements and programs called for by the Phase 11 Plan. ATTACHMENT Consultants and Participating Agencies BUS 2-5 Attachment Consultants and ]Participating Agencies Professional Consultants: Lead Consultant: Questa Engineering Corporation www.questaec.com Biology Sub-consultant: Morro Group www.morrogroup.com Agencies participating in the study: Government Agencies: City of San Luis Obispo,www.ci.san-luis-obispo.ca us County of San Luis Obispo—Zone 9 Agricultural Research Initiative(ARI) project,www.cagr.calpoly.edu/cagr/ari/ San Luis Obispo County—Planning Department U.S. Army Corps of Engineers Regulatory Branch,www.spl.usace.army.mil/co/co5.html National Marine Fisheries Service California Department of Fish and Game U.S. Fish and Wildlife Service US Environmental Protection Agency Central Coast Regional Water Quality Control Board,www.swrcb.ca.gov/rwgcb3/ Landscape Architecture Department Cal Poly San Luis Obispo, suntzu.larc.calpoly.edu/gislab/ BioResource &Agricultural Engineering Department Cal Poly San Luis Obispo, www.calpoly.edu/—brae/ Coastal San Luis Obispo Resource Conservation District, www.coastalrcd.org Non profit corporations: San Luis Obispo Land Conservancy, http://www.slonet.org/vv/land—con/ BUS 2-6