Section 2 Stormwater Management Program Water Quality Assessment

Transcription

1 Section 2 Stormwater Management Program Water Quality Assessment 2.1 Stormwater Management Area Assessments Local Environmental Setting The, population 10,350 according to 2000 US census, generally lies on the narrow coastal shelf between the ocean and the coastal hills. A map of the City is located in Appendix C. The City is within the north coastal area of San Luis Obispo County and is about 12 miles north of the city of San Luis Obispo. The covers an area of approximately 6 square miles. The topography is generally hilly to mountainous, with development and agriculture concentrated on the coastal plain and valleys. The City is primarily a residential community with an economy based on the tourism/visitor-serving businesses. Census 2000 data shows that 24 percent of the population is over the age of 65 and approximately 20 percent of the City s residences are vacant or used as seasonal second residences. The built out projected population for the is 12,500. Almost the entire community of Morro Bay lies within the Coastal Zone. The Local Coastal Program Land Use Plan (LUP) applies to all but a small area of the City. Development within the City is regulated by the Coastal Land Use Plan, the Zoning Ordinance, the General Plan, the Building Ordinance, and other Municipal Codes when appropriate. The City operates and maintains a variety of facilities, including parks, streets, sidewalks, bike trails, public buildings, a corporation/maintenance yard, open space, a waste water treatment plant, a water treatment plant reverse osmosis facility, and harbor support facilities. Drainage A watershed is the area of land that drains to a specific body of water. The City lies within several watersheds (Appendix D) including Chorro Creek Basin watershed, Morro Creek Basin watershed, Toro Creek watershed, Alva Paul Creek watershed, Noname Creek drainage area, and small unnamed watersheds. The City plans to delineate these unmapped watersheds as the GIS mapping of the storm drain system is being completed. The major watersheds within the City are Morro and Chorro Basin watersheds. The Chorro Basin watershed is approximately 27,670 acres including approximately 2,300 acres of mudflats, tidal wetlands, and open water habitat. The City lies within a small portion of this watershed; approximately 0.09% of developed land is within the total watershed and 0.91% of undeveloped land is within the total watershed. Section 2 Page 1

2 The Morro Basin watershed is approximately 15,400 acres with approximately 1.77% of developed land and 0.91% of undeveloped land within the total watershed area. The smaller watersheds; Alva Paul Creek is approximately 1,125 acres and Noname Creek is approximately 280 acres. The land use percentages have not yet been determined in these smaller watersheds. In 1987 the Wallace Group completed a storm drain master atlas for the City of Morro Bay (Appendix E). The storm drain system has changed very little since this time. The drainage for the City consists mostly of overland to surface drainage ways draining into the storm drain conveyance system and then draining to the bay or ocean. Some areas of the City drain directly to the bay or ocean (i.e. Embarcadero area) or to a creek that then drains to the bay or ocean. 2.2 Local Watershed Efforts Watershed Management Approach USEPA defines the watershed management approach as having the following components: problem identification (pollutants of concern), stakeholder involvement, and integrated actions. The has complied with this definition by identifying pollutants of concern in section, 2.3 and 2.4. The City has held several stakeholders meeting and has also participated in stakeholder meetings county wide. The City s integrated actions are within each proposed Best Management Practices (BMP) for the six minimum control measures. The watershed management approach can also encompass issues such as flood control, habitat restoration, and water supply, which are not specifically regulated by the CWA. In contrast to the traditional command and control regulatory approach, the watershed approach is characterized by collaborative planning among the various stakeholders in a watershed. The solutions derived from this approach typically take longer to develop, but are more tailored to the unique problems and characteristics of individual watersheds. As expected, each watershed has a unique combination of environmental problems, existing organizations, and restoration opportunities, requiring a patient and flexible approach to developing solutions. In an effort to achieve the watershed management approach, the City currently participates in the SLO County Partners for water quality, a group where the City collaborates with other stakeholders within the county. The city also works with Morro Bay National Estuary Program and their Comprehensive Conservation and Management Plan, which is discussed on the following page. Section 2 Page 2

3 Morro Bay National Estuary Program (MB NEP) After years of grassroots campaigning, Morro Bay was designated as a State Estuary in 1994 and as a National Estuary in In 2000, the Morro Bay National Estuary Program published its Comprehensive Conservation and Management Plan (CCMP) to address the following seven priority problems for Morro Bay: Sedimentation Bacteria Nutrients Loss of freshwater flow during the dry season Heavy metals and toxic pollutants Loss or degradation of habitat Loss of steelhead The CCMP includes 61 Action Plans that target the priority problems and rely on collaboration of stakeholders for funding and implementation. In addition to targeting the seven listed priority problems, the actions include Public Outreach and Education and seven actions that address Land Acquisition, Drainage, TMDLs, Urban Runoff, Stream Geomorphology and Water Quality, Volunteering Monitoring, and a Watershed Crew. The actions target the seven priority issues as well as public education and outreach. Many actions address source pollution and are consistent with California Coastal Commission s Source Pollution Control Program. The City s SWMP includes best management practices that are consistent with the action plans related to urban runoff. The CCMP Action Plans include: CC-4 Urban Runoff: Implement urban storm water Best Management Practices (BMPs) to reduce pollutants entering Morro Bay and its tributaries. SED-1: Increase use of management measures for road maintenance and construction activities to reduce damage to streams and the Morro Bay estuary. SED-2: Install new and maintain existing sediment traps in order to reduce the delivery of sediment to Morro Bay. BACT-2: Upgrade existing pump-out facilities (where needed), improve accessibility, and provide new pump-out facilities at additional locations where feasible, to minimize the impacts of waste discharges and improperly functioning marine sanitation devices (MSDs vessel restrooms). BACT-3: Remove illegal moorings (and prevent future illegal occurrences) in the back bay to reduce the potential for high-concentrations of bacterial pollution in the vicinity of shellfish harvest areas. Section 2 Page 3

4 BACT-5: Decrease levels of bacteria from live aboard boats (both within and outside the limits). BACT-8: Support the establishment of an off-leash dog park and provide supplies around high-use recreational areas for the pick-up of pet waste, and promote protection of creek beds from horse trails during low flow periods. NUTR-4: Implement Best Management Practices (BMPs) to decrease fertilizer runoff from residential and other urban areas. HMT-2: Implement marina (harbor and waterfront) Best Management Practices (BMPs). HMT-3: Support the s development and design of a new environmentally friendly boat haul-out and maintenance facility for large vessels (generally over 30 feet). EDU-1: Conduct general public outreach and education focused on the value of a healthy environment and the role of individuals in protecting the natural resources of the Morro Bay watershed. EDU-2: Develop educational materials and programs regarding marine pollution and habitat issues geared toward the commercial and recreational boating community of Morro Bay. MB NEP conducts First Flush monitoring and Urban Watch programs. The pollutants of concern identified by MB NEP are as follows: E. Coli Turbidity ph Total Dissolved Solids (TDS) Orthophosphates Metals (zinc, copper and nickel) 2.3 Stormwater Pollutants of Concern (POC) The analyzed existing water quality data to determine the Pollutants of Concern impacting waterbodies within the permit coverage area. Water quality monitoring data from the Central Coast Ambient Monitoring Program (CCAMP) were reviewed to determine the parameters that have been monitored and the pollutant load trends that have been reported. Next, key water quality reports and Watershed Management Plans for waterbodies within the city limits were reviewed to look for local water quality problems caused by stormwater runoff. See Table 2.1 for a listing of the water quality reports and Section 2 Page 4

5 watershed management plans that were reviewed for stormwater pollution impacts on waterbodies located within the city limits. After careful review of the local water quality reports and watershed management plans for waterbodies in the permit coverage area, Chorro Creek was identified as an impaired waterbody in the CWA (d) list. As a result, there are several reports conducted in this area. Morro Creek is not identified as an impaired waterbody, but CCAMP has conducted monitoring in this area and pathogens were identified as pollutants of concern for Morro Creek. Morro Bay is listed as an impaired waterbody in the CWA (d) list. Table 2.1 Key Local Water Quality Reports and Watershed Management Plans for Waterbodies in the Permit Coverage Area Water Quality Document Watersheds Covered Internet Hyperlink, where available San Luis Obispo Integrated Regional Water c.htm Management Plan Morro Bay National Estuary Program Comprehensive Conservation Management Chorro Creek Plan for Morro Bay Central Coast Regional Water Quality Control Board Basin Plan Watershed Management Initiative, January 2002 Water Quality Priorities and Targeted Projects Draft 2005 Basin Plan Triennial Review Priority List Final 2001 Basin Plan Triennial Review Priority List Central Coast RWQCB 303(d) Investigations and TMDL Projects RWQCB 2006 CWA 303(d) List of Impaired Waterbodies RWQCB Central Coast Ambient Monitoring Program (CCAMP) Heal the Bay Annual Beach Report for San Luis Obispo City See Table 2.3 See Table 2.2 Coastal watersheds t/basinplan/index.htm %202002,%20Final%20Document,%20Rev ised% pdf t/wmi/documents/wmi2004waterqualitypr ioritiesappendixdfinal.pdf t/basinplan/triennialreview/documents/att achatrl2004revised pdf t/basinplan/triennialreview/documents/ t/tmdl/303dandtmdlprojects.htmattachb. pdf s/programs/tmdl/docs/303dlists2006/epa/st ate_usepa_combined.pdf lt.asp Section 2 Page 5

6 2.4 Total Maximum Daily Loads (TMDLs) In general, Pollutants of Concern within the generally fall within one of two categories: 1) pollutants associated with soil disturbance and 2) pollutants entering the system from other surface runoff. These pollutants are generally associated with land use and enter waterways through runoff from urban surfaces. Section 303(d) of the Clean Water Act requires States to identify waters not attaining applicable water quality standards and to develop Total Maximum Daily Loads (TMDLs) for pollutants. The State complies with this requirement by periodically assessing the conditions of rivers, lakes, and bays and identifying them as impaired if they do not meet water quality standards. These waters, and the pollutants causing impairment, are placed on the Clean Water Act Section 303(d) List of Impaired Waterbodies. In addition to creating this list of impaired waterbodies, the Clean Water Act mandates that states rank each waterbody by factors (such as the severity of the problem, the potential to restore beneficial uses, the availability of data, etc.) and develop TMDLs for each waterbody listed. A TMDL is the amount of a particular material that a waterbody can assimilate on a regular basis and still remain at low enough levels to protect the beneficial uses designated for that waterbody. A TMDL is approved by the Regional Water Quality Control Board, the State Water Resources Control Board, and the US Environmental Protection Agency. Once a TMDL is approved, it establishes the following: 1) An allowable amount of a pollutant to a waterbody; 2) Proportional responsibility for controlling the pollutant; 3) Numeric indicators of water quality; and 4) Implementation to achieve the allowable amount of pollutant loading. TMDLs are developed by analyzing information from existing or commissioned studies and/or by stakeholders interested in the waterbody or conditions being investigated. TMDL development results in a definition of water quality problems in a waterbody or watershed, a numeric value for the TMDL, and an implementation plan that identifies how the problems will be solved and the TMDL achieved. The implementation plans identify new requirements, based on existing regulations, in conjunction with other existing water quality management activities. The implementation plans identify which requirements or activities apply to which agencies, landowners, resource managers, and/or the public. Table 2.2 lists the waterbodies in the permit coverage area that are impaired by pollutants and the potential sources of pollutants. The pollutants identified on the 303(d) list are Pollutants of Concern for the. Section 2 Page 6

7 Table 2.2 Clean Water Act Section 303(d) Listed Waterbodies and TMDL Priority in the Permit Coverage Area The TMDLs are a Pollutant of Concern for the, but it appears that the City is not a significant contributor according to the potential sources. Note: From the 2006 Clean Water Action Section 303(d) List of water quality limited segments. _combined.pdf Waterbody Pollutant TMDL Requirement Potential Sources Status* Chorro Creek Fecal Coliform B Unknown Chorro Creek Nutrients A Municipal Point Sources Agriculture Irrigated Crop Production Agricultural storm runoff Chorro Creek Dissolved Oxygen A Unknown Chorro Creek Sedimentation/Siltation B Agriculture Irrigated Crop Production Range grazing riparian and/or upland Agricultural storm runoff Construction/Land Development Road Construction Resource extraction Hydromodification Channelization Streambank modification/ destabilization Channel erosion Erosion/siltaton Natural sources Golf course activities Nonpoint source Morro Bay Dissolved Oxygen A Unknown Section 2 Page 7

8 Waterbody Pollutant TMDL Requirement Potential Sources Status* Morro Bay Pathogens B Range Grazing Upland Urban Runoff/Storm sewers Septage disposal Natural sources Nonpoint Source Morro Bay Sedimentation/Siltation B Agriculture Irrigated Crop Production Construction/Land Development Resource Extraction Channelization Channel Erosion * (A) Those requiring TMDLs, (B) addressed by USEPA approved TMDLs Table 2.3 lists the TMDL s that have been approved for the impaired waterbodies in the permit coverage area for this SWMP. A complete listing of the status of all of the TMDL s in the region can be seen on the internet at Table 2.3 Approved TMDLs for Clean Water Act Section 303(d) Listed Waterbodies in the Permit Coverage Area as of June 2006 TMDL Morro Bay TMDL and Implementation Plan for Pathogens, Including Chorro and Los Osos Creeks Morro Bay TMDL and Implementation Plan for Sediment Including Chorro Creek, Los Osos Creek and the Morro Bay Estuary Status Final approval January 20, 2004 November 19, 2003 effective date Final approval January 20, 2004 December 3, 2003 effective date Section 2 Page 8

9 The City attended a water quality assessment stakeholders meeting with the Central Coast Regional Water Quality Control Board and various stakeholders on May 15 th, At this meeting the Pollutants of Concern for Morro Bay were discussed. As discussed earlier, the impaired waterbody identified was Chorro Creek for pathogens and sediment/siltation, which has an approved TMDL. Also included in the impaired waterbody list was Morro Bay for Dissolved Oxygen, which does not have an approved TMDL. Additional POC discussed were pathogens in Morro and Toro Creeks and organochlorine and metals (arsenic, cadmium) for Morro Bay. Heal the Ocean s beach report card was also included in the discussion. The Morro Bay City Beach and Morro Creek received an A in the dry weather season and a B in the wet weather season in This report shows an improvement from pervious years report cards of C in wet weather. The report indicates an A in the past three year for the dry seasons. The Heal the Bay s beach report card states; Morro Strand State Beach, projection of Beachcomber Dr and Morro Bay City Beach, projection of Atascadero Rd. both received an A+ for wet and dry season year round. Morro Bay City Beach, Morro Creek (south Side) and Morro Bay City Beach, 75 feet north of main parking lot received an A for both dry and wet season year round. The possible pollutants sources were identified by stakeholders as follows: Restaurant Discharges Harbor Activities Street Runoff Landscaping Business maintenance and repairs (power washing and painting related discharges) Construction Homeless encampments These pollutant sources were identified through anecdotal information and will require additional assessment during the City s permit period. The SWMP addresses possible pollutants of concern with various BMPs in the six minimum control measures (see section 4). Section 2 Page 9

10 This SWMP addresses the Pollutants of Concern identified in the TMDLs that have been approved as follows: Morro Bay (Chorro Creek) Pathogens TMDL See Section 4 for a detailed description of the BMPs listed below. BMPs/Projects as Cited in TMDL Boat management pump-outs Manage live aboard boating situation Educate Public about proper boat waste disposal Pet waste management Discussion/Actions as Cited in TMDL Upgrade pump-out facilities, provide new facilities improve accessibility Continue issuing permits to live aboard, continue with inspections Educate public about proper waste disposal Create an off leash dog park, provide supplies to pick-up pet waste, ordinance How the Pollutant of Concern (Pathogens) is Addressed in this SWMP The pump-out facilities have been upgraded, tidelands park pump-out station is also very accessible. The Yacht Clubs pump-out station has also improved the accessibility. See BMP IL9 Ongoing BMP MO10 Ongoing BMP MO10 BMP IL7 Adopt and enforce a Pet Waste Management Ordinance BMP PE15 Pet waste management public education and outreach campaign which includes mutt mitt stations in various locations within the City. Morro Bay (Chorro Creek) Sediment TMDL The is not currently identified in the Morro Bay (Chorro Creek) Sediment TMDL as a responsible discharger. However, the s SWMP does address the sediment and siltation in several BMP s within the six minimum control measures. Section 2 Page 10