DEQ Completes Clean Water Plan For Willamette Watershed

The plan is required because portions of the Willamette River and its tributaries do not meet water quality standards for mercury, temperature, and bacteria.

The Willamette River just north of Salem Photo by: Tim King

(SALEM) - The Oregon Department of Environmental Quality has issued its clean water plan for the Willamette River watershed. The Willamette Basin Total Maximum Daily Load (TMDL) Order signed by DEQ Water Quality Administrator Lauri Aunan requires pollution sources to implement actions to improve water quality.

Through this TMDL, the DEQ expects to reduce mercury with a goal of removing fish consumption advisories; protect people from bacteria during water contact recreation; and protect threatened and endangered fish species.

Implementing the plan will be carried out in partnership with Oregon residents, businesses, local governments, Tribal Nations, and state and federal agencies. Achieving the improvements will require significant commitments and investments from all partners.

The DEQ has already begun working with communities, businesses, rural landowners and others to reduce mercury, temperature and bacteria. The TMDL makes provisions for additional monitoring, evaluation, and adaptive management to achieve water quality standards and protect beneficial uses over time.

“In the early 1940s the Willamette River was so polluted that in some stretches, fish died within minutes of being put into the water. The health of the River has greatly improved over the past decades, but serious problems remain,” said Aunan. “This clean water plan will continue to improve the health of the Willamette River watershed for mercury, bacteria and temperature.”

To develop the TMDL, the DEQ worked closely with state, federal, and local governments, Tribal Nations and stakeholder groups representing industries, conservation groups, agriculture and forestry. The Willamette TMDL Council met 28 times over four years. DEQ issued a draft TMDL for public comment in October 2004, and issued a revised TMDL for public comment in April 2006.

Mercury:

The accumulation of mercury in fish is a well-recognized environmental problem throughout the United States. Mercury can cause damage to the brain and nervous system. Small children and the developing fetus are most sensitive to mercury’s toxic effects. The primary way that humans are exposed to mercury is through the consumption of fish or seafood containing elevated levels of mercury.

The DEQ’s preliminary analysis indicates that the majority of the mercury (96%) in the Willamette watershed comes from non-point sources such as the erosion of native soils containing mercury and the runoff of atmospherically-deposited mercury from urban and rural lands.

Mercury is also discharged at low levels by some industrial facilities and domestic wastewater treatment facilities (4%). The TMDL was developed to reduce the amount of mercury in the river so that mercury levels in fish will be reduced, with a goal of eliminating the fish consumption advisories.

The mechanism by which mercury travels and accumulates in fish is complex and not fully understood. In addition, a large amount of mercury falls onto land from air emissions that originate outside the watershed. For these reasons, the TMDL will be updated as we improve our understanding and knowledge about mercury in the watershed.

Beginning in 2007, DEQ will require selected municipal and industrial facilities to (1) increase monitoring and reporting of mercury, and (2) develop and implement plans to reduce mercury in discharges. DEQ will also work with communities and businesses to reduce soil erosion that can carry mercury to rivers. Best management practices to reduce soil erosion will also occur on agricultural and forest lands. By 2011, DEQ will evaluate the effectiveness of these strategies and update the mercury TMDL as necessary.

Bacteria:

Parts of the Willamette River and some of its tributaries occasionally have levels of bacteria that can make people sick if they ingest the water when swimming or during other water contact. The primary cause of excess bacteria is water that runs off rural and urban lands when it rains. This storm water runoff picks up soil and pollution and takes it into rivers and streams.

Industries and communities covered under National Pollutant Discharge Elimination System (NPDES) storm water permits are required to implement best management practices to reduce storm water pollution. Agricultural Water Quality Management Plans developed by local stakeholders and approved by the Oregon Department of Agriculture will address bacteria pollution coming from agricultural activities.

Portland’s Combined Sewer Overflow (CSO) program is on schedule to meet the DEQ’s Order to reduce CSO discharges by 94% when finished in 2011.

Temperature:

At times, the Willamette River and its tributaries are too warm to support healthy salmon. Warm water interferes with salmon migration and spawning, and decreases chances of juvenile survival. Salmon are more susceptible to disease when water temperatures are warmest.

Oregon’s water quality standards for temperature are established to protect fish habitat for cold water species such as salmon and trout. A principal cause of stream heating has been removal of trees and other shade-producing vegetation from stream banks.

Dams also affect stream temperature. Wastewater from industrial and municipal treatment facilities is a less significant source of heat when discharged to streams, but still needs to be addressed.

The TMDL requires actions to reduce temperature and improve water quality to protect fish.

DEQ water quality permits will include more stringent heat limits as permits are renewed over the next five years. Industries and municipal sewage treatment plants will need to meet permit limits.

Options to meet permit limits will include removing discharges from the river during times when heat is of most concern; reducing the temperature of the discharges; and offsetting the effects of heated discharges through actions such as improving fish habitat, providing cold water refuges for fish, and streamside plantings.

The DEQ will require dams operated by the US Army Corps of Engineers and others to take steps to reduce temperature and improve habitat and water quality for fish through Temperature Management Plans.

The DEQ is partnering with watershed councils, soil and water conservation districts and other entities like the Oregon Watershed Enhancement Board, the Willamette Partnership, and the US Department of Agriculture to leverage resources that reduce the impacts of non-point source pollution.

Through activities such as establishing shade-producing streamside vegetation and re-connecting floodplain areas, temperatures will be reduced. State agencies including the Department of Agriculture and Department of Forestry are working with landowners to protect and establish streamside vegetation.

More work needed to identify and solve other toxic concerns Increasingly stringent pollution controls have significantly improved Willamette River water quality over the years. Through this new clean water plan to reduce mercury, bacteria and temperature, there will be continued improvements.

At the same time, federal studies of the Willamette River have found significant levels of pesticides and toxic chemicals other than mercury. Currently, the DEQ does not have resources to systematically monitor toxics, determine the level of threat to public health and the environment, and target resources toward solutions. DEQ is requesting Governor and legislative approval of funding to establish targeted, watershed-based toxic pollutant monitoring and evaluation, beginning in the Willamette River.

With this funding the DEQ would identify the sources of toxic pollution that pose the greatest threat to public health and the environment, and take steps to reduce those toxics.