IDEM TMDL 101

Everything you wanted to know about Total Maximum Daily Loads

Presentation Overview

• The Total Maximum Daily Load Program (TMDL)

• The TMDL Development Process

• The TMDL Document

Presentation Overview

• The Total Maximum Daily Load Program (TMDL)

• The TMDL Development Process

• The TMDL Document

What Is a Total Maximum Daily Load?

• Identifying the pollutant

• Determining the current level of the pollutant

• Calculating the amount of the pollutant that a waterbody can receive and still meet water quality standards

• A report of pollutant sources, needed reductions, and actions necessary to improve water quality

• A tool to guide watershed planning

History of Indiana TMDL Program

• 2001 IDEM submits first TMDL • 2005 IDEM meets submission goals from U.S. Environmental Protection

Agency (U.S. EPA) • 2006 IDEM develops and submits TMDLS

– IDEM developed first state-led multistate TMDL

• 2012– U.S. EPA submission goals have been continuously met since 2005– IDEM has developed a TMDL template designed to meet the nine elements of a

Watershed Management Plan (WMP)– IDEM has 1,055 approved TMDLs

What Is a Watershed?

The Definition of a TMDL

• The sum of allowable loads from point sources, waste load allocations (WLA) and nonpoint sources, load allocations (LA) plus a margin of safety (MOS)

What Does a Total Maximum Daily Load Provide?

• Information- A description of the watershed and the water quality data on the impairment

• Sources- Overview of the potential sources of the pollutant• Loads- The amount of the pollutant of concern that a

waterbody can receive and still meet water quality standards or targets that apply to the watershed

• Reductions- A list of the pollutant load reductions necessary to meet the water quality standards or targets that apply to the watershed

• Implementation- A tool to guide watershed planning and restoration activities

TMDL Development Selection Process• Water Quality Reports

• 305(b) - Assess water quality and report to U.S. EPA, Congress• 303(d) - Compile list of impaired waters • Product - Indiana Integrated Water Monitoring and Assessment Report

• 303(d) list• Start with 1998 and use subsequent lists to complete watershed

assessment

• New process• Watershed group request• Special projects

Allocations

• Waste load Allocation (WLA)– WLAs are the contributions from point sources– Point sources are much easier to identify since they

have a discharge point or direct outlet to the stream– Point sources have some type of monitoring or

information and are therefore easier to assign loadings

Allocations• Load Allocation (LA)

– LAs are the pollutant contributions from nonpoint sources, which are not directly regulated

– "Diffuse" pollution, generated from large areas with no particular point of pollutant origin, but rather from many individual places

– Pollution that cannot be traced to a regulated direct outlet or discharge point

Allocations

• Margin of Safety (MOS)– MOS may be either implicit or explicit– Implicit

• Incorporated into the TMDL through conservative assumptions in the analysis

– Explicit• Expressed in the TMDL as loadings set aside for the

MOS

Presentation Overview

• The Total Maximum Daily Load Program (TMDL)

• The TMDL Development Process

• The TMDL Document

What Is the TMDL Process?• Review 303(d) list and sampling data • Conduct additional monitoring • Reassess waterbodies• Gather information and produce draft TMDL report• Draft TMDL stakeholder meeting• 30-day comment period• Revise draft TMDL and respond to comments on draft final

TMDL• Submit TMDL to U.S. EPA and receive final TMDL approval

What Are Impaired Waters?• Waterbodies sampled for water quality, assessed by

IDEM and listed on the 303(d) List of Impaired Waters

• Waterbodies where a “use” is adversely affected– Fishable, Swimmable, Drinkable

• Waterbodies then sampled for TMDL magnitude and extent of impairment

• Streams are then reassessed

Indiana’s Most Common Water Quality Impairments

• Problems:– E. coli– Impaired Biotic Communities– Statewide fish consumption advisory

• Mercury• PCB

Internal Data Gathering• ArcGIS map of area• 303(d) listing

information• Assessment database• Land use

• Confined Feeding Operations

• Concentrated Animal Feeding Operations

• NPDES permits• NPDES violations• Enforcement cases

External Data Gathering• Stakeholders

• Soil and Water Conservation Districts

• Health Departments

• Federal and State Government Agencies

• Watershed Groups

• Purdue Extension Offices

• Universities

Presentation Overview

• The Total Maximum Daily Load Program (TMDL)

• The TMDL Development Process

• The TMDL Document

The TMDL Document

• Overview of watershed condition• Identification of sources• Discussion of analytical process• Load reductions needed• Current and past water quality improvement

efforts• Recommended actions

What Does a Total Maximum Daily Load Provide?

• Information- A description of the watershed and the water quality data on the impairment

• Sources- Overview of the potential sources of the pollutant• Loads- The amount of the pollutant of concern that a waterbody can

receive and still meet water quality standards or targets that apply to the watershed

• Reductions- A list of the pollutant load reductions necessary to meet the water quality standards or targets that apply to the watershed

• Implementation- A tool to guide watershed planning and restoration activities

TMDL Goals• IDEM is committed to a stakeholder-driven

process

– Collecting information from local stakeholders

– Providing staff to communicate with stakeholders and share information

– Watershed specialists assist with watershed management plan (WMP) development

Putting it All Together

Locally Led Work to Improve Water

Quality

Nonpoint Source Grants

Program

Total Maximum

Daily Loads

(TMDL)

Watershed Specialists

303(d) List and 305(b) Report

Questions?

Staci GoodwinSenior TMDL Project ManagerOffice of Water QualityIndiana Department of Environmental Management100 North Senate AvenueIndianapolis, Indiana 46204

Phone: (317) 308-3387Fax: (317) 308-3219E-mail: sgoodwin@idem.IN.gov