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THE CITY OF LAGUNA BEACH MONITORING PLAN FOR THE HEISLER PARK ASBS PROTECTION AND PRESERVATION PROJECT ASBS Grant #10-410-550 COMPLETED PLAN PREPARED BY Will Holoman, City of Laguna Beach Refer correspondence to: Will Holoman, City of Laguna Beach 505 Forest Drive Laguna Beach, CA 92651 Telephone: (949) 497-0781 E-mail: [email protected] Approval:______________________________________________________________ Date Project Description and Monitoring Objectives The baseline conditions along the shoreline adjacent to Heisler Park are of elevated bacteria levels attributable to anthropogenic sources. The source of the bacteria along the coastline is generally attributed to drainage from adjacent developed areas. Heisler Park is currently designed to drain directly to the ocean through its subterranean storm drains and sheet flows on the surface. The objective of the Phase III project is to reduce the amount of bacteria reaching the adjacent ASBS by routing nuisance flows and flows from small storm events through treatment control BMPs then diverting any remaining water to the sanitary sewer system. Nuisance flows will be reduced by incorporating Smarttimers and irrigation improvements throughout the project area. The predicted outcome of this project is the reduction of bacteria levels in the ocean by eliminating flow from storm drain lines to the beach during non-storm and small storm conditions. The BMPs implemented in Phase III include site design, treatment and diversion. The site design BMP is the regrading and recontouring of the land within the project boundaries to direct storm flows away from the beach. The innovative site design includes tilted pathways, contoured swales and terraces built with retaining walls to contain sediments and push surface flows into the treatment control BMPs. Smarttimers, water efficient sprinkler heads and drought tolerant vegetation will reduce nuisance flows by reducing on-site water waste. The treatment control BMPs are vegetated areas where flows will infiltrate for plant use and be filtered through vegetation to remove nutrients and bacteria. Flows which overwhelm the capacity of the treatment control BMPs will enter the subterranean drain system, then flow into a sump where a pump will divert the water directly to the sanitary sewer system. Flows not diverted will be treated with catch basin inserts. The combination of BMPs and the diversions should be adequate to handle all flows but major rain events. The goal of the monitoring program is to quantify the amount of bacteria and water treated through the BMPs and diverted from the beach. Research findings will build on monitoring data gathered through the CBI funded diversion projects upstream of the Heisler Park project area. Combining data from ocean water monitoring, the two projects will quantify the total amount of bacteria and flow removed from the beach outfalls. The data will be compiled and maintained by the City of Laguna Beach until submission to the State. The information will be shared with the SWRCB, the SDRWQCB, and upon request to other State, federal and local agencies and organizations. Detailed Sampling Information The City of Laguna Beach will coordinate all monitoring activities for this project. The Project Analyst will be responsible for data collection, but subcontractors may be utilized to assist in collecting and analyzing data. Agreements with subcontractors will be 2 administered through the City. The City will also document all monitoring and construction activities and expenditures in quarterly progress reports throughout the project term. CEQA documentation and all necessary permits have been secured by the City. A Quality Assurance Project Plan (QAPP), Monitoring Plan and Project Assessment Evaluation Plan (PAEP) will be submitted by the City and approved by the State prior to the start of project monitoring. Water meter, storm flow, debris mass and bacteriological data are of primary interest in the assessment of the project with respect to stated goals. The timing of the project dictates that the field data collection activities focus on the post-construction phase for bacteriological, debris, irrigation flow and diversion flow monitoring as pre-construction data has already been collected. Once the post-construction field data has been collected, it will be compared to five prior years of pre-construction ocean bacteria and water flow data to form a comprehensive picture of pre- and post-construction conditions. Ongoing studies at Heisler Park will be included in the analysis and results of the post-construction monitoring for Phase III will be used in combination with results from Phases I and II to create a comprehensive final report. Bacteriological and debris monitoring will take place at diversion units located along Cliff Drive adjacent to the Park. Water samples will be taken from diversions quarterly, as available, to quantify the bacteria levels in the runoff. The sediment and debris pumped from the unit by city crews will be tracked to calculate mass of debris captured. Flow and bacteria data from other monitoring projects may be utilized to enhance the data set for this location. Bacteriological and flow monitoring will take place in the sumps where nuisance flows are collected for diversion. The sumps represent the culmination of all subterranean drain lines within the project prior to discharge onto the beach and are the points at which flows are diverted to the sewer. The flow is monitored by counting the cycles of the pump as it is triggered to divert water to the sewer lines. The known quantity of water pumped per cycle multiplied by the number of pumping cycles will provide the necessary flow data. Pump cycle data will be taken monthly, as available. Quarterly bacteriological samples will also be taken at this location, as available, and subsequently correlated with flow data to quantify the amount of bacteria diverted away from the ocean. Because the benefits of infiltration and site design BMPs are difficult to assess using typical flow and sampling techniques, and the benefits of Smarttimers and irrigation improvements must be quantified, the water meter data for Heisler Park will allow a comparison of water usage pre- and post-construction. Precipitation data taken during the post-construction monitoring period will be used to evaluate the effectiveness of site design BMPs by correlating rain events to bacteria levels and other project criteria as appropriate. Flow, debris, bacteria, water meter and precipitation data will be taken over a period of one year post-construction, then analyzed in a comprehensive report with the goal of 3 assessing the overall bacteria reduction realized in the receiving waters with Park improvements as well as the benefits of individual elements of the Park design. Both a Draft and a Final report will be submitted to the State for approval. Pre- and post-construction water samples use the following methods to determine bacteria levels: Parameter Method/range Units Total coliform – water matrix SM 9222-B CFU/100 ml Detection Limit* 1 Fecal coliform – water matrix Enterococcus – water matrix SM 9222-D SM 9230-C CFU/100 ml CFU/100 ml 1 1 The County of Orange monitors the bacteria levels in storm drain outlets and the ocean at several nearby locations. Data from these ongoing monitoring efforts, as well as beach closure data, will be analyzed for one and five years, respectively, prior to and one year post-construction. Pre-construction data will be collected as follows: 1-year Sediment and debris volume from diversion Water meter flow data Orange County storm drain and ocean bacteria data Beach closure data 4 5year X X X As available X Post-construction monitoring will begin by June 30, 2008 and the preliminary draft final report is anticipated in August 2009. The framework for post-construction sampling is as follows: Monthly Sample diversion sumps for bacteria Record data from pump counter Pump sediment and debris from diversions, record volume Water meter flow data Orange County storm drain and ocean bacteria data Beach closure data Precipitation data X Quarterly As Available* X X X X X X X X *Samples cannot be taken when sumps are dry, some data may have inconsistent sampling frequencies Geographical Information Heisler Park is located along the Pacific Ocean shoreline immediately northwest of Main Beach in Laguna Beach. The coordinates for the project site are approximately: 33d32’38”N, 117d47’32”W. Monitoring sites are located as follows: Site ID CDS-2 CDS-3 CDS-4 Site Name Myrtle CDS Jasmine CDS Aster/Gazebo CDS D-1* Central Diversion D-2* South Diversion OLB00 OLB05 HEISLRUP HEISLRDN 4636* 4647* 10066* 8125* Main Beach Heisler Park North Heisler Upcoast Heisler Downcoast Heisler Water Meter Heisler Water Meter Heisler Water Meter Heisler Water Meter Parameters Bacteria, Debris Bacteria, Debris Bacteria, Debris Flow, Bacteria, Debris Flow, Bacteria, Debris Bacteria Bacteria Bacteria Bacteria Flow Flow Flow Flow *Locations approximate, TBD upon project completion 5 Latitude 33d32’39.9”N 33d32’38.5”N 33d32’35.3”N Longitude 117d47’34.0”W 117d47’26.0”W 117d47’20.3”W 33d32’36.8”N 117d47’33.3”W 33d32’35.0”N 117d47’19.4”W 33d32’31.97”N 33d32’42.85”N 33d32’33.78”N 33d32’32.57”N 33d32’42”N 33d32’38”N 33d32’42”N 33d32’38”N 117d47’11.77”W 117d47’45.39”W 117d47’20.88”W 117d47’21.80”W 117d47’35”W 117d47’26”W 117d47’35”W 117d47’26”W Site Location Map 6 Monitoring Site Map 7 Resource and Time Constraints The Heisler Park Project is expected to produce long-term positive impacts in the adjacent waters of the Pacific Ocean, but the data to be analyzed for the final report will span only one year after construction. It is anticipated that the data will show a decrease in bacteria levels at the beach and a reduction in water use for the park. The data will also serve to estimate the volume of bacteria and quantify the mass of debris diverted away from the ocean during the first year of BMP operation therefore demonstrating tangible benefits of the project on Heisler Park ASBS. The results of the monitoring analysis for this final phase of the project will be combined with results from the previous two phases to produce a more comprehensive, longer-term study of the positive impacts of the project on the ASBS. All relevant monitoring data from Heisler Park will be examined to determine if it would better characterize the overall effectiveness of the BMPs and therefore enhance the final report. 8