Building a Better Total Maximum Daily Load Reopener

Date / Time:
Wednesday, Sep 17 10:55am to 11:25am
Garden 1 & 2
Track / Session:

Over the past 15 years, the development of Total Maximum Daily Loads (TMDLs) has dominated the efforts of regulators and regulated agencies alike. Now, as TMDLs are put into permits and effluent limitations and drive requirements, the realities of implementing the TMDLs and the costs associated with them are setting in. Additionally, when most of the TMDLs were developed, imperfect information led to inclusion of TMDL reopeners to allow reevaluation prior to final compliance. However, many of the reopeners are behind schedule and many agencies are struggling to effectively influence the TMDL reopener process. In this talk we will use case studies from Southern California TMDLs to support a discussion of how to effectively influence TMDL reopeners. The talk will provide a framework that stormwater program managers can use to:

1. Evaluate options to determine the best strategies for the TMDL reconsiderations.
2. Separate the “what’s wrong with the TMDL” from “what will make a difference for compliance”.
3. Develop a plan and schedule to effectively influence the reopeners.

As agencies look towards reopeners, a myriad of technical and regulatory options, such as site-specific objectives and natural source exclusions, are often available to them to pursue. Additionally, as monitoring and special studies are conducted, more and more data are generated that can be used to support the reopener process. Finally, with the new permit requirements and work that has been done to develop implementation plans, agencies now have tools to demonstrate the costs and effectiveness of implementing best management practices to implement TMDLs. While agencies have more and more information available to them, navigating and deciding the best combination of implementation actions, studies and monitoring to support an effective TMDL reopener can be challenging.

Additionally, given the number of uncertainties and assumptions generally made during TMDL development, it can be tempting to try and gather information to “fix” all of the technical inaccuracies in the TMDLs. However, fixing the technical issues may not result in any meaningful changes that impact the compliance requirements for the stormwater program. This talk will provide tools for evaluating when fixing a technical issue will support meaningful changes to the TMDL.

Finally, not all actions can be directly implemented into a TMDL. Some require additional regulatory actions, such as a basin plan amendment to incorporate a site-specific objective, that can be very time consuming. The talk will include a discussion of ways to identify a realistic schedule and plan for the TMDL reopener that incorporates other regulatory actions that may be needed.

The talk will focus on bacteria and metals TMDLs and present lessons learned from recent TMDL reopener processes. Audience engagement will occur through case studies and interactive feedback on issues audience members have faced during TMDL reopener processes.

Primary Speaker:
Ashli Desai, Larry Walker Associates
ASHLI DESAI is a Vice President with Larry Walker Associates (LWA) and has 19 years of experience in regulatory assistance, watershed management, and TMDL development and implementation. Ms. Desai is primarily responsible for overseeing LWA’s TMDL and regulatory work in Southern California, including NPDES permit assistance; regulation and policy review and comment; TMDL review, development and implementation; agricultural conditional waiver assistance; and special study development and implementation. Ms. Desai specializes in facilitating coordination between municipal agencies, stakeholder groups, and regulatory agencies to provide regulatory solutions that allow implementation of stakeholder developed strategies for solving water quality problems. Ms. Desai has a B.S. in Earth Systems, Environmental Technology and an M.S. in Civil and Environmental Sciences and Engineering from Stanford University
Supporting Speaker 1:
Chris Minton, Larry Walker Associates