Newport Bay Watershed Executive Committee. February 20, 2013

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1 Newport Bay Watershed Executive Committee February 20, 2013

2 AGENDA ITEM 1 APPROVAL OF MINUTES Mary Anne Skorpanich, County of Orange

3 AGENDA ITEM 2 ELECTION OF OFFICERS Mary Anne Skorpanich, County of Orange

4 AGENDA ITEM 3 SEDIMENT PROGRAM UPDATE AND PATH TO DELISTING Mary Anne Skorpanich, County of Orange Wanda Cross, Santa Ana Regional Water Quality Board

5 Sediment Program Update Sediment management activities for past 30 years Year 14 of TMDL implementation in Newport Bay Watershed Since March 1999 sediment TMDL partners have met requirements

6 Key Accomplishments Maintenance & expansion of basins Channel stabilization Restoration of Upper Newport Bay Construction & agricultural best practices Study for Serrano Creek & Borrego Canyon Wash Watershed-wide completion of channel erosion surveys Monitoring & reporting

7 Current Activities Study on long term funding for maintenance of In-Bay basins Exploring options for stabilizing Serrano Creek Monitoring Bay restoration project Ongoing best practices & TMDL-required monitoring and reporting Working with Regional Board Executive Officer to modify monitoring & reporting requirements

8 In-Channel Basins, 2012 BASIN MAXIMUM CAPACITY AVAILABLE CAPACITY Cubic Yards Cubic Yards Tons % 1 232, , , ,876 71,360 86, ,297 52,362 63,

9 Rationale for Changing TMDL Requirements Discontinue monitoring that no longer adds meaningful data Increase monitoring efficiency Increase flexibility on how sediment is managed throughout the system To allow sediment removal in additional locations To facilitate opportunities for source control upstream

10 B S Unit I In-bay Basins Unit II 10

11 2013 Revisions Requested 1. Discontinue monitoring Santa Ana-Delhi, Sand Canyon, Bonita Creek, and Marshburn stations Stations have very low sediment yield. Further information is not beneficial.

12 2013 Revisions Requested 2. Discontinue scour studies and available capacity requirements for Marshburn Retarding Basin Marshburn Basin has been modified to a natural Treatment System wetland, no longer functioning as a sediment basin.

13 2013 Revisions Requested 3. Revise the rainfall trigger for foothill retarding basin scour surveys to 150% mean rainfall Surveys collected during years of 100% mean basin rainfall have not shown a significant drop in available sediment basin capacity from the prior year.

14 2013 Revisions Requested 4. Revise the monitoring schedule for bathymetry and vegetation studied in the Bay to at least every 7 years Completion of the Upper Newport Bay Restoration Project has increased the sediment capacity of In-bay Basins requiring less frequent data collection.

15 Summary of Changes Sought Administrative changes: 4 changes above to Monitoring & Reporting Program Transmitted to Regional Board in January Basin Plan Amendment required: Eliminate requirement to monitor capacity of three In-Channel Basins

16 PATH TO DELISTING Wanda Cross, Santa Ana Regional Water Quality Control Board

17 Presentation Topics 1. TMDL Background 2. Technical Issues Compliance with numeric targets (TMDL) Need for in-channel sediment trapping basins Evidence for continued impairment in San Diego Creek and Newport Bay 3. Plan for the Future Sediment control projects Protecting Newport Bay Delisting TMDL = Total Maximum Daily Load (mandated by the Clean Water Act to ensure achievement of water quality standards in impaired waterbodies)

18 TMDL Background 1998 TMDL Based on 1983 Boyle Plan developed by stakeholders Purpose is to restore impaired beneficial uses Focus is protection of Newport Bay Extensive public comment/involvement prior to adoption TMDL numeric targets are intended to help interpret water quality standards but do not replace those standards (beneficial uses and water quality objectives)

19 TMDL Background Implementation Reduction in suspended sediment concentrations Stabilization of eroding channels (with notable exceptions) Newport Bay dredging restoration of navigation use

20 Annual Net Sediment Load [(tons/yr)/acre] San Diego Creek San Juan Creek Sweetwater River Tijuana River Regional Sediment Loading Comparison San Luis Rey River S.D. Creek , without basin maintenance TMDL Target expressed per unit area S.D. Creek , with basin maintenance Santa Margarita River Santa Ana River San Diego River Average Streamflow (million gallons per day) Reference: (Inman and Jenkins, 1999; data: , streams draining peninsular ranges)

21 TMDL Numeric Targets Compliance Indicator Sediment Load to S. D. Creek Numeric Target 62,500 tons (10-yr avg.) Compliance Summary In compliance Sediment Load to Newport Bay Min. Depth In-Bay Unit I/III Min Depth In-Bay Unit II Newport Bay * Habitat Acreages 62,500 tons (10-yr avg.) -7 ft MSL -7 ft MSL 1% change In compliance beginning in 2008 (with maintenance of S.D. Creek basins) In compliance (1998 dredging project) Out of compliance: In compliance: 2009 current Out of compliance by 2004 survey Continued expansion of saltmarsh Saltmarsh = 350 acres, TMDL baseline = 277 acres (largest extent of saltmarsh since 1989) * TMDL establishes habitat target as primary measure of success of the TMDL

22 In-Channel Basins and Numeric Target (latest 10-year averages: 2001/ /11) Sediment Monitoring Ten-Year Average Load (tons/year) Discharged to Newport Bay 50,434 Removed from in-channel basins (TMDL requirement) 16,500* Total (including sediment removed from basins) 66,934 TMDL Target 62,500 *Another 44,000 tons accumulated in the three basins after the last removal in (an additional 4,400 tons/year for the 10-year period to 2011)

23 Dredging Cost Comparison Project Sediment Removed (cubic yards) Project Cost ($) Unit Cost ($/cubic yards) San Diego Creek Basins 2 & 3 216,800 $3.8 M $ $ Upper Newport Bay ,349,700 $47.3M 5 $ IRWD presentation to NBWEC, February 17, After subtracting royalties earned by IRWD 3- Excluding IRWD staff costs 4- Including IRWD staff costs ($5/yd 3 ) 5- All reported Army Corps costs (Design Documentation Report, 2011) 6- Phase I = $17.4/yd 3, Phase II = $25.7/yd 3

24 S.D. Creek Operations & Maintenance Plan (2009) Basin 2 from Campus Dr., Jan (flow = 885 mgd)

25 Sediment Loading to Newport Bay Sediment Load to Newport Bay (tons) 700, , , , , , ,000 Annual Load (tons) Ten-Year Avg. (tons/yr) TMDL (tons/yr; 10-yr avg) TMDL = 62,500 tons/year (10-yr avg) s 600, , , , , , ,

26 Evidence of Impairment: Bio-assessment Project 20 Sediment Depostion Score Deposition Score optimal: suboptimal: marginal: 6-10 poor: ,000 2,000 3,000 4,000 5,000 6,000 7,000 Red squares= S.D. Creek Elevation (feet) sites

27 San Diego Creek Bio-assessment Sites Region 8 Stream Bio-assessment Project: (IBI= Index of Biotic Integrity, scale of 0 to 100) East Yale (2006) IBI = 23 (poor) Culver (2008) IBI = 14 (very poor) Laguna Freeway (2008) IBI = 9 (very poor) West Yale (2009) IBI = 3 (very poor) (San Diego Creek sites marked in red)

28 San Diego Creek at Confluence with Peters Canyon Wash, February 2011

29 Evidence of Impairment: Newport Bay Eelgrass Upper Newport Bay: 8 acres in 1969; 0.04 acres in 2010 Lower Newport Bay: Evidence of light-limitation (CRM, 2010) Shallow eelgrass acreage has declined steadily from 30 acres in 2004 to 20 acres in 2010 Despite a reduction in fluvial sediment loads to the Upper Bay, superfine particles remain in suspension and are transported into Lower Newport Bay. These superfine particles reduce the levels of available light needed for eelgrass growth (CRM, 2010) Eelgrass and Macroalgae, Balboa Island,

30 Sediment Control Project: Jeffrey Basin (SD Creek between Jeffrey Road and Sand Canyon Avenue) June, 2010 October, 2012 Potential for beneficial reuse declines as sediment moves downstream due to higher organic matter and silt/clay content, increased salinity, and increased contaminant concentrations.

31 Sediment Control Project: Borrego Wash (pictures from County of Orange, FBI El Toro property, ) Lower reaches (one mile) traverses federal property (FBI). Preliminary stabilization plan (2010). Approx. $2.5 million to stabilize entire 1-mile segment; costs for stabilizing individual subsections begin at approx. $200,000 Eroding creek bank Failing grade control Upper reaches (one mile) to be stabilized by Shea-Baker Properties in conjunction with development of Baker Ranch.

32 Sediment Control Project: Restoration of Degraded Foothill Habitat Limestone Whiting Park in 2013, after 2007 Santiago Fire and large storm event of Dec , 2010 (rainfall=7 in.) Existing Plan: Nature Reserve of Orange County (NROC), Habitat Restoration and Enhancement Plan (2003)

33 Proposed Aqua Chinon Restoration (NROC 2010)

34 TMDL Delisting Pathway 1. Meet All Numeric Targets Newport Bay habitat Loading (without in-channel basins) Minimum depths 2. Beneficial Uses Supported Sediment does not impair established beneficial uses Eelgrass restoration in Newport Bay San Diego Creek benthic habitat not impaired by sediment 3. Plan to Protect Newport Bay Sustainable plan to ensure future sediment removal from the in-bay basins

35 Recommended Action Receive and File.

36 AGENDA ITEM 4 FECAL COLIFORM REPORT UPDATE Mary Anne Skorpanich, County of Orange

37 Purpose TMDL Task 9 requires an updated Fecal Coliform TMDL report. Recommendations for revisions to the Basin Plan, the Fecal Coliform TMDL, and the 303(d) list of water quality limited segments. TMDL Task 8 requires development of a plan for evaluation and source monitoring to determine compliance with the Waste Load Allocations and Load Allocations assigned to four source categories. Proposed Source Monitoring Plan to comply with this requirement.

38 Focus of Report Recommended revisions in following three categories Basin Plan Fecal Coliform TMDL List of Impaired Waters

39 Revision to Basin Plan Consideration of natural sources Reference System and Anti-degradation approach Natural Source Exclusion Approach Outdated Fecal Coliform water quality objectives

40 Revision to Fecal Coliform TMDL Updated problem statement Revised TMDL numeric targets Revised TMDL load allocations and waste load allocations Revised SHEL compliance date Routine monitoring program

41 Revision to List of Impaired Waters Source monitoring plan TMDL revision process

42 Recommendations for List of Impaired Waters revision Monitoring locations that meet de-listing criteria should be removed from routine monitoring program Revise monitoring locations to reflect current areas of impairment

43 Revision to List of Impaired Waters

44 Recommended Basin Plan Changes Adoption of REC-1 Saltwater Enterococcus water quality objective Rescinding REC-1 Fecal Coliform water quality objective for bays and estuaries

45 Recommended TMDL Changes Revision of the problem statement to reflect the most current data Inherent differences in fecal indicator bacteria concentrations during wet and dry weather conditions in Newport Bay Outdated Fecal Coliform water quality objectives

46 Next Steps Gathering comments on draft report Revise report and additional data analysis Transmit final draft to Regional Board with recommendations Consideration of natural sources Update the water quality objectives for bacteria applied to estuarine and bay waters designated for the contact recreation (REC-1)

47 Implementation of Recommendations Update TMDL problem statement Revise TMDL Numeric Targets Revise TMDL load allocations and waste load allocations Process for approval by: Regional Water Board State Water Board Office of Administrative Law U.S. Environmental Protection Agency

48 Recommended Action Receive and file

49 AGENDA ITEM 5 EXECUTIVE OFFICER REPORT Mary Anne Skorpanich, County of Orange

50 AGENDA ITEM 6 EXECUTIVE COMMITTEE COMMENTS

51 AGENDA ITEM 7 PUBLIC COMMENTS

52 Next Meeting Date May 15, 2013