The document discusses Low Impact Development (LID) as a site-specific and conceptual approach aimed at minimizing the negative impacts of hydromodification and stormwater pollution by mimicking the natural hydrologic cycle. It outlines the evolution of stormwater management, legislative progress, and implementation challenges, with a focus on new developments and significant redevelopments. Additionally, it emphasizes the environmental and cost-effective benefits of LID, along with funding opportunities for sustainable water quality projects.

1. Low Impact Development Adjusting to the New Storm Water Paradigm

2. What is LID? A site-specific, conceptual approach to minimize the detrimental effect of hydromodification LID Goal - Mimic the natural hydrologic cycle Site-specific – Designs will change per locale Conceptual – Qualitative not quantitative Approach – Needs to be addressed and included from the inception of the project Development – LID requirements are currently focused exclusively on new developments and significant* redevelopments Hydromodification – the unnatural redirecting of stormwater

4. Evolution of Storm Water Treatment Three Main Phases Phase I: Conventional Model (pre-70’s) Collect and Convey PROBLEM: Point-source pollution, hydromodification Phase II: Retention Model, BMPs (80’s and 90’s) Flow, Volume and Source/Treatment Control PROBLEM: Hydromodification, maintenance Phase III: Low Impact Design Model (2000+) Mimicking Natural Hydrology PROBLEM: Adequate treatment? Flooding? Implementation? Involvement?

5. Progression of Legislation Clean Water Act of 1972 Set goals for all national waters to be free of all discharges causing pollution Required TMDLs for impaired watersheds NPDES Permits (Section 402 CWA) Storm Water Pollution Prevention Plan Storm Water Management Plan Development Standards Plan State Board’s Sustainability Resolution (2005-2006) NPDES Permits now shifting to LID Contra Costa County Phase I NPDES Permit (2005) Stockton Phase I NPDES Permit (Dec. 2007) Upcoming statewide Phase II NPDES Permit (~ March 2009)

6. What is LID? Site-specific, conceptual approach of developing property to minimize the detrimental effect of hydromodification and pollution LID Goal - Mimic the natural hydrologic cycle Site-specific – Designs will change per locale Conceptual – Qualitative not quantitative Approach – Needs to be addressed and included from the inception of the project Development – LID requirements are currently focused exclusively on new developments and significant* redevelopments Hydromodification – the unnatural redirecting of stormwater

7. Hydrologic Cycle

8. Natural Infiltration

9. Our Mokelumne

10. Example of Erosion caused by Hydromodification

11. Natural Balance of Erosion and Deposition After Lane (1955) as cited in Rosgen (1996)

12. Environmental Benefits of LID Cost Effective - less treatment, less conveyance, less maintenance, less fines, etc. Mitigates downstream flooding, erosion and aggradation Helps control water quality Preserves stream base for riparian ecosystems Helps recharge groundwater Preserves natural temperatures in receiving waters Multifunctional: landscaping, aesthetics, native vegetation, social benefits, open space use, etc. Resilient and adaptable to various climates

13. Functional Benefits of LID Treats first flush runoff Majority of contaminants Treats common small/medium-size storm Majority of storms Design includes overflow for large storms Conventional MS4 used as back-up Aesthetically pleasing Easy to maintain

14. Ways to Mimic Natural Hydrology Know your natural hydrology! Soil quality improvement Native and drought tolerant vegetation Trees Maximize pervious surfaces Disconnect impervious surfaces from storm drain - disconnect downspouts, rain barrels, Bioretention – Rain Gardens, swales Green Roofs?

15. LID Examples

16. The Big Challenge - Implementation Statewide Quantitative Standards TMDLs Sizes of IMPs Regulator-based Local Qualitative Standards Permittee-based Matching local conditions The Main Need – Local Involvement Planning Department, Engineering Firms, Construction Firms, Landscape Architects, Environmental Consultants, Field Technicians…

17. Current Implementation Approaches for LID Contra Costa County - C3 Guidebook 4 th Edition IMPs for 4% of impervious surface Present challenge is to find proper soil type www.cccleanwater.org/newdevelopmentc3/ Santa Barbara’s New NPDES Permit http://www.santabarbaraca.gov/Resident/Community/Creeks/Storm_Water_Management_Program.htm City of Stockton’s new NPDES Permit Revision of SWQCCP currently in progress Stakeholder meetings in progress www.stocktongov.com/mud/General/stormwater/SQCCP.cfm Phase II NPDES Permits Expected March 2009

18. Recent Funding Opportunity – Proposition 84 Matching Grants for sustainable, long-term water quality projects which reduce and prevent stormwater contamination of rivers, lakes and streams LID projects will take priority for grants 20% match for most cities and towns in delta area $250,000 to $500,000 grants per project 2 Phases of grants http://www.waterboards.ca.gov/water_issues/programs/grants_loans/prop84/index.shtml

19. New Developments?! Where? Will that really make a difference? We have to start somewhere Retrofitting is too costly Use of grant money may show the success of LID and direct projects to existing developments

20. LID Opportunities for WGR Expert knowledge of NPDES requirements Ensuring clients with LID compliance Knowledge of local soils and hydrology Filling in needs to facilitate implementation Geographic Informational Systems (GIS) Offering compliant LID design concepts Constructing and maintaining LID sites

21. Closing Comments Unexplored Territory Ahead Opportunity for Sustainable Change A whole new market Share Ideas. Let’s go forward intelligently. Foster awareness. Goal – See WGR as the Central Valley Leader in innovative LID solutions!

22. Thanks for Listening! Any Questions or Comments Please call Chris @ (209) 334-5363 ext. 214 WGR Southwest, Inc. 315 W. Pine St. Lodi CA 95240

23. Restoring Soil Function

24. Soil Health

25. Riparian Zone