Agua Hedionda Watershed Management Plan

1. Agua Hedionda Watershed Management Plan Watershed Planning Group Meeting June 5, 2008 Carlsbad, CA

2. Agenda Update on LID Research Preliminary Recommendations for Watershed Management ActionsImplementation Next Steps

3. Update on LID Research

4. Bioretention • Bacteria removal significantly better than swales • Likely to need underdrain system, which increases cost • Without irrigation, need drought-tolerant plants that can also withstand inundation • Recommend sedimentation forebay to reduce risk of clogging • More research needed for proper design in arid environments

5. Porous Pavement • Many different technologies, rapidly evolving field • Potential for some infiltration, even on poor soils • With proper design, may not need underdrains • Frequent vacuum sweeping (e.g., annually) needed to maintain effectiveness • Could be used for sidewalks and patios in addition to large non-commercial parking areas.

6. Cisterns • Cisterns have been successfully tested in CA in demonstration projects • Store runoff from rainy season to use for site irrigation during dry season • Applicable for both residential and non-residential uses • Needs further analysis to determine cost-effectiveness • New development – can amortize cost with mortgage

7. Bioretention Porous Pavement Cistern City of Encinitas, Roadside GrassCrete parking Courtesy of Arid Solutions, Inc

8. Stream Buffers • Multiple functions – stream channel stability, pollutant trapping and uptake, temperature moderation, habitat • Recommended width varies depending on goals • 30 – 100 feet for pollutant removal • 100 – 300 feet for habitat/ecosystem function/wildlife corridors • Channel protection width varies by stream order – room for channel migration (e.g., 4X bankfull width) • Current CA local buffer ordinances mostly from 50 – 100 feet

9. Irrigation • Estimates of 40-50 inches/yr in CA, leads to nutrient-rich irrigation return flow • Technologies allow irrigation to be demand-driven • Can use drought-tolerant plants to reduce demand • Irrigation essentially required by CA fire safety law • Maintain a “defensible space” around buildings • 30 feet minimum “home defense zone”, vegetation with high moisture content

10. Preliminary Recommendations for Watershed Management Actions

11. Actions: New Development Site Management • Basic LID Implementation • Reduce site impervious area • Swales • Extended dry detention • Stream buffers

12. Extended Dry Detention Swale City of Encinitas, Volleyball Court/ Detention Area Stream Buffer Photograph Courtesy of EOA, Inc.

13. Actions: New Development Site Management • Enhanced LID Implementation • High level of effort to reduce site impervious area • Disconnect impervious surfaces where possible, direct runoff to pervious areas to maximize infiltration • Minimize disturbance of pervious surfaces • Bioretention • Porous pavement • Cisterns/water harvesting

14. Actions: New Development Site Management • Incorporate use of “basic LID” techniques into local codes and ordinances • Track compliance with stormwater management and LID • As requirements increase (e.g. TMDL), consider use of enhanced LID techniques • Test feasibility of porous pavement, cisterns, and bioretention without irrigation

15. Actions: Preservation • 25 properties • 386 acres to preserve • $38 to $95 million in total acquisition costs (fee simple acquisition) • Average cost: $98,000 to $246,000 per acre

16. Actions: Preservation • Field evaluation • Landowner outreach • Compare with cultural resource priorities • Identify/secure funding sources • Identify/secure stewardship organizations • Develop stewardship plan • Annual acquisition workshop • Update prioritization tool

17. Actions: Riparian Buffer Restoration • 27 properties • 129 acres to restore • $9.8 to $19 million in total acquisition and restoration costs • Average cost: $76,000 to $147,000 per acre

18. Buffer Restoration Priorities Actions: Riparian Buffer and Wetland Restoration

19. Actions: Riparian Buffer Restoration • Field evaluation • Landowner outreach • Compare with cultural resource priorities • Preliminary design and cost estimate • Secure needed permits • Identify/secure funding sources • Identify/secure stewardship organizations • Restoration planning and design • Develop stewardship plan • Annual acquisition workshop • Update prioritization tool

20. Actions: Wetlands Restoration • 14 properties • 61 acres to restore • $4.2 to $13 million in total acquisition and restoration costs • Average cost: $69,000 to $213,000 per acre

21. Wetlands Restoration Priorities

22. Actions: Wetlands Restoration • Field evaluation • Landowner outreach • Compare with cultural resource priorities • Preliminary design and cost estimate • Secure needed permits • Identify/secure funding sources • Identify/secure stewardship organizations • Restoration planning and design • Develop stewardship plan • Annual acquisition workshop • Update prioritization tool

23. Actions: Stream Restoration • 12 reaches to restore • 31,500 feet, or 6 miles to restore • $9 to $11 million in restoration costs

24. Stream Restoration Opportunities Actions: Stream Restoration

25. Actions: Stream Restoration • Landowner outreach • Compare with cultural resource priorities • Preliminary design and cost estimate • Secure needed permits • Identify/secure funding sources • Identify/secure stewardship organizations • Restoration planning and design • Develop stewardship plan • Annual acquisition workshop • Update prioritization tool; coordinate with sewer and storm drain infrastructure programs

26. Actions: BMP Retrofit • 2,870 acres of high priority parcels • Located in high priority subbasins based on existing runoff and loading • Five retrofit demonstration sites (coincident with stream restoration sites) • Demonstration BMPs include dry detention, bioswale, rainwater harvesting, permeable pavement, media filters, trash traps

27. BMP Retrofit Opportunities Actions: Riparian Buffer and Wetland Restoration

28. Actions: BMP Retrofit for 5 Demonstration Sites • Landowner outreach • Preliminary design and cost estimate • Secure needed permits • Identify/secure funding sources • Final planning and design

29. Actions: BMP Retrofit for Untreated Parcels • Site selection and BMP feasibility • Landowner outreach • Design and costing • Secure needed permits • Secure funding

30. Actions: Monitoring and Enforcement • Long-term stream and lagoon monitoring • Long-term wetlands monitoring • Inspections/maintenance of sanitary sewer • Inspections/maintenance of storm drainage system • Construction site inspection • Stormwater BMP Inspection • Tracking Watershed Indicators

31. Actions: Citizen Stewardship/Public Outreach • Collaborative Watershed Council • Education of local boards to gain support for watershed management • Development of citizen education materials • LID workshops and training • Annual awards program • Management partnerships

32. Actions: Sustained Funding and Support • Secure grants • SWRCB (Prop 84); DWR (Prop 84 and 1e); County IRWM (Prop 84); EPA 319(h) • Coordinate with partner agencies • Wetland Recovery Project; Wildlife Agencies; MSCP/MHCP programs; Channel Maintenance Programs • Mitigation programs • Mitigation Banks; Individual Project Mitigation Needs • Watershed Council Support • Wetland Recovery Project; Department of Conservation; Local Jurisdictions; Local Businesses

33. Implementation

34. Your advice needed • Potential funding sources • Responsible group(s) • General timelines • See handout

35. Next Steps

36. Next Steps • June 9-16 - Review of Draft Implementation Table • June 12-16 – Review of Focus Area Recommendations • July 10 – Draft Watershed Management Plan • July 17- Final WPG Meeting to comment on Draft Plan