MONITORING PLAN FOR THE SONGS’ WETLAND MITIGATION PROJECT Prepared for the staff of the California Coastal Commission by: Mark Page Stephen Schroeter Daniel Reed and Mark Steele In consultation with Richard Ambrose, Peter Raimondi, and Russell Schmitt Updated January 2016 Monitoring plan for SONGS wetland restoration project Table of Contents Executive summary………………………………………………………..……………………………. 4 1.0 Introduction…....................................................................................................................... 5 2.0 Evaluation of condition compliance……………………………………………………………… 6 2.1 Performance standards…………………………………………………………………….. 6 2.2 Reference wetlands…………………………………………………………………………. 7 2.3 Determination of similarity………………………………………………………………….. 8 2.4 Monitoring period and project compliance………………………………………………... 9 3.0 Sampling methods and data collection…………………………………………………………. 10 3.1 Methods for assessing the performance standards……………………………………... 10 3.2 Data collection………………………………………………………………………………. 11 3.3 Strategy for dealing with unusual events…………………………………………………. 20 4.0 Data management………………………………………………………………………………… 21 4.1 Daily field and data transfer procedures………………………………………………….. 21 4.2 Data entry and quality assurance…………………………………………………………. 21 4.3 Data storage and preservation…………………………………………………………….. 22 5.0 Dissemination of results………………………………………………………………………….. 23 6.0 Management of the mitigation site……………………………………………………………… 23 6.1 Inlet management………………………………………………………………………….. 23 6.2 Topography………………………………………………………………………………….. 24 6.3 Control of weeds and other invasive exotic species……………………………………. 24 7.0 Construction impact monitoring……….………………………………………………………….24 8.0 References……………………………………………………………………............................. 25 Figure 1. The locations of tidal creeks and sections of main channel/basin to be sampled for fish within San Diegutio Lagoon using enclosure traps and beach seines…………….. 27 Figure 2. The location of stations to be sampled for fish using enclosure traps and beach seines in Tijuana Estuary………………………………………………………………………… 28 Figure 3. The location of stations to be sampled for fish using enclosure traps and beach seines in Mugu Lagoon and Carpinteria Salt Marsh………………………………………….. 29 Figure 4. The location of plots to be sampled for birds in San Dieguto Lagoon…. …………….. 30 2 Monitoring plan for SONGS wetland restoration project Figure 5. The location of plots to be sampled for birds in Tijuana Estuary……………………….. 31 Figure 6. The location of plots to be sampled for birds in Mugu Lagoon and Carpinteria Salt Marsh…………………………………………………………………………………………. 32 Figure 7. The location of transects in seasonal marsh sampled as reference sites and transects in the constructed transition zone to be sampled annually………...……………... 33 Appendix 1. The definition of compliance and the determination of similarity in the context of the SONGS mitigation projects………………………………………………………………. 34 Appendix 2. Methods for sampling gobies with enclosure traps in southern California wetlands…………………………………………………………………………………………… 43 Appendix 3. Variation in estimates of species richness and density of wetland fish fish caused by different methods of purse and beach seining………………………………. 64 Appendix 4. Spatial and temporal variation in fish assemblages in southern California coastal wetlands: implications for post-restoration monitoring at San Dieguito Lagoon and reference sites……………………………………………………………………. 100 Appendix 5. Spatial variation in benthic macroinvertebrate density in southern California coastal wetlands: implications for post-restoration monitoring at San Dieguito Lagoon and reference sites……………………………………………………………………. 139 Appendix 6. Estimating bird species richness and density in coastal wetlands of southern California: application to the SONGS bird monitoring plan…………………………………. 187 Appendix 7. List of exotic species that occur in or could invade San Dieguito Lagoon………. 220 Appendix 8. Planned acres of subtidal, mudflat, and salt marsh habitat for the San Dieguito Wetlands Restoration Project (from the Final Restoration Plan, SCE 2005)……………………………………………………………………...……………….. 225 3 Monitoring plan for SONGS wetland restoration project EXECUTIVE SUMMARY Through its 1991 and 1997 coastal permit actions (permit # 6-81-330 and 6-81-330) the California Coastal Commission (CCC) adopted permit conditions that require Southern California Edison (SCE) and its partners to create or substantially restore 150 acres of tidal wetlands at an approved location within the Southern California Bight. A revised preliminary plan for wetland restoration at the San Dieguito River Valley, submitted to the CCC by SCE on November 3, 1997, calls for the excavation of approximately 115 acres of upland to create tidal wetland and the enhancement of 35 acres of existing tidal wetland through the continuous maintenance of the tidal inlet in perpetuity. Created and restored habitats in this plan include a subtidal basin, channels, and intertidal mudflats and vegetated salt marsh. Condition A (Wetland Mitigation) of the CCC coastal development permit for SONGS (hereafter, SONGS permit) requires that monitoring of the wetland restoration be done over the full operating life of SONGS Units 2 & 3. This monitoring will be done to determine project compliance with the performance standards specified in the SONGS permit. In accordance with Condition D (Administrative Structure) of the SONGS permit, scientists retained by the Executive Director of the CCC will develop a Monitoring Plan to guide the monitoring work and will oversee the monitoring studies outlined in the Plan. The SONGS permit provides a description of the performance standards and the monitoring required for the wetland mitigation project. This Monitoring Plan closely adheres to the monitoring requirements of the permit and includes: (1) a description of the process used to evaluate condition compliance, including a list of performance standards by which the success of the mitigation wetland will be judged, (2) descriptions of the specific sampling methods and analyses that will be used to evaluate each of the performance standards, (3) an explanation of how project data will be managed and archived for future use, and (4) a description of how the results from the monitoring program will be disseminated to the CCC, the applicant, and all other interested parties. Management issues relevant to the SONGS wetland mitigation requirement include inlet maintenance, responses to excessive changes in topography, and adverse effects of exotic species. SCE has a plan for managing the inlet in perpetuity to ensure uninterrupted tidal flushing of the restored wetland. This plan provides conditions that would trigger the need for additional maintenance dredging at the inlet (SCE 2004). Topographic degradation of the wetland and berms may occur over time as a result of sedimentation and scour. If topographic surveys and aerial photographs indicate major topographic degradation has occurred, then the appropriate corrective action (e.g., dredging) will be taken to reconfigure the wetland to its “as designed” condition. Exotic species may invade restored habitats. If invasive exotic species are found in the restored wetland, and these species could adversely affect the success of the restoration, experts working in this field will be consulted and a program to control the spread of these species will be developed. 4 Monitoring plan for SONGS wetland restoration project 1.0 INTRODUCTION Through its 1991 and 1997 coastal permit actions (permit # 6-81-330-A, formerly 6-83-73) the California Coastal Commission (CCC) adopted permit conditions that require Southern California Edison (SCE) and its partners to create or substantially restore 150 acres of tidal wetlands at an approved location within the Southern California Bight. The purpose of this condition is to serve as out-of-kind mitigation that compensates for past, present and future impacts to fish caused by the operation of San Onofre Nuclear Generating Station (SONGS) Units 2 & 3. On June 11, 1992, the CCC approved SCE’s choice of the San Dieguito River Valley as the restoration site that meets the minimum standards identified in the SONGS permit and best meets the objectives of the wetland mitigation requirement. On April 9, 1997, the CCC reaffirmed its prior determination that San Dieguito River Valley is the restoration site and determined that SCE can propose an additional site for restoration only if achieving all 150 acres of restoration at San Dieguito River Valley becomes infeasible due to hydrology or other engineering concerns. The CCC also determined that up to 35 acres of enhancement credit could be obtained for inlet maintenance if wetland restoration is done at San Dieguito. A preliminary plan for wetland restoration at the San Dieguito River Valley was submitted to the CCC by SCE on September 30, 1997. In November 1997, the Commission approved SCE’s revised preliminary wetland restoration plan as largely conforming with the minimum standards and objectives stated in the permit. The revised plan called for the excavation of approximately 115 acres of upland to create tidal wetland and the enhancement of 35 acres of existing tidal wetland through the continuous maintenance of the tidal inlet in perpetuity. Created and restored habitats in this plan include a subtidal basin, channels, intertidal mudflats, and vegetated salt marsh. In addition, the plan included the construction of least tern nesting sites, flood control devices