DEQ’s Twin Falls Region is improving water quality in the region through partnerships, cooperation, and support from government agencies, businesses, and the public.  Specific accomplishments are outlined below.

Water quality improvement plans called "total maximum daily loads (TMDLs)," have been completed for all or part of six "subbasins" in the region and have been approved by the U.S. Environmental Protection Agency (EPA).  The goal of a TMDL is to set limits on pollutant levels in water bodies that don’t meet water quality standards so that they will meet standards in the future.

Two additional TMDLs will be sent to EPA for approval in 2005.  Upon this approval, only one subbasin-wide TMDL will be left to complete in the region.  This TMDL should be finished in 2006.  Once this TMDL is developed, all subbasins in the region will have undergone the TMDL process. 

Additional TMDLs will also be developed; however, these will be for single streams within subbasins that have already had TMDLs developed.  These single-stream TMDLs are much less complicated than the subbasin-wide TMDLs that have been completed to date. 

Once a TMDL is complete, programs are implemented to improve water quality and achieve TMDL goals.  All approved TMDLs in the Twin Falls Region are in various stages of implementation. Support for improved water quality by the general public, agricultural interests, land management agencies, and state agencies has brought about improvement in the surface waters of the region. 

The implementation projects come in many forms and take place on private, as well as public, lands.  Projects on private lands to reduce nonpoint source pollution abound in the area and are supported by federal, state, and private funds.  For example, §319 subgrants have funded 15 different water quality improvement projects in the region; grant money to support an additional six projects has recently been applied for. 

Two major irrigation canal companies on the Snake River (Twin Falls Canal Company and Northside Canal Company) have spent nearly $2,000,000 on wetland and sediment basin construction projects specifically for the Mid-Snake and Upper Snake Rock TMDLs.  With support from the canal companies, most farmers with irrigated fields have constructed sediment basins to control sediment runoff during the irrigation season.  Cost for construction and maintenance for these systems is considerable and is borne by the individual farmers. 

Additional projects on public lands, by land managers such as the U.S. Forest Service, the Bureau of Land Management, and the Idaho Department of Lands, have further improved water quality. 

Millions of dollars have also been spent by point source pollution permitted municipalities, food processors, and others to reduce point source pollution into surface waters. 

Four areas in the Twin Falls Region have been designated as nitrate priority areas and require ground water quality management plans be developed to outline strategies to help reduce nitrate loading to ground water from land use activities.  With DEQ’s assistance, local ground water quality advisory groups have completed two plans: Twin Falls Ground Water Management Plan (DEQ Publication, December 2001: pdf 659 kb, 59 pages) and Cassia County Ground Water Management Plan (DEQ Publication, June 2004: pdf 2.3 mb, 62 pages).

These plans are being implemented through classroom education for children, an educational video, a land management pilot project (funded by §319 funds), and county-wide comprehensive planning.     

Work has begun on the remaining two plans.  A planning team for the  Minidoka County Water Quality Management Plan has formed and begun meeting.  The Bliss Water Quality Management Plan is being developed concurrently with the Bliss Nitrate Priority Area Best Management Practices Demonstration Project (a §319-funded project).

The Twin Falls Regional Office has been working with Blaine County decision-makers to develop and implement a countywide drinking water protection plan and county wellhead protection ordinance.  DEQ is providing technical assistance and acting as a liaison among local officials, the Blaine County Drinking Water Protection Coalition, and other stakeholders within the county.  More detail on this successful partnership can be found in DEQ’s 2005 Annual Report (pdf 864 kb, 20 pages).   

DEQ is also providing technical assistance to other community water systems in the region to develop and implement local drinking water protection plans, update existing plans in preparation for state recertification, and facilitate source water assessment of new public drinking water sources as they are developed.