The new comment period opens today and continues through Oct. 15, 2009. The Spokane River/Lake Spokane Dissolved Oxygen Water Quality Improvement Plan, often referred to as the total maximum daily load (TMDL) report, will guide work toward a healthier Spokane River in compliance with water quality standards for dissolved oxygen.
A public meeting is planned for 6-9 p.m., Thursday, Sept. 24, 2009, at the Spokane Community College’s Sasquatch Room in the Lair Building #6, 1810 N Greene St., Spokane.
“This document has been controversial and the subject of many years of community discussion,” said Water Quality Program Manager Kelly Susewind. “We heard the community’s concerns during the previous public comment period and we have worked hard on this draft plan to address those concerns. Now it’s time to take one more look.”
The water quality improvement plan outlines how the community will reduce phosphorus and other substances in the Spokane River and Lake Spokane to prevent algae blooms, increased growth of aquatic plants and the related declines in Lake Spokane’s dissolved oxygen. Under the federal Clean Water Act, when a body of water fails to meet water quality standards for certain pollutants, Ecology must study the problem and produce a plan to improve water quality.
Phosphorus is the primary nutrient causing excess algae and plant growth in the Spokane River and Lake Spokane. It behaves like fertilizer, causing algae and other aquatic plants to grow and thrive. When the plants decompose, they use up dissolved oxygen that fish need to breathe. More algae means less oxygen.
In addition, unsightly algae blooms can become toxic and cause nuisance smells or human skin irritations. They can make Lake Spokane unhealthy for swimming, and compromise its ecological balance.
The Spokane River / Lake Spokane Dissolved Oxygen Water Quality Improvement Plan will lead to reducing phosphorus pollution from industrial and municipal pipes by more than 90 percent. Its phosphorous limits for industrial and municipal discharges are among the most stringent in the country.
Unique to this improvement plan, the industrial and municipal “point-source” (from a pipe) dischargers are required to help reduce phosphorus from other diffuse, “non-point” sources as well. Non-point sources include farms, septic systems, stormwater runoff, animal waste, and fertilizers used at home. In addition, the plan gives Avista Corp., operator of Long Lake Dam, a portion of the responsibility to improve dissolved oxygen levels in Lake Spokane.
The U.S. Environmental Protection Agency (EPA), working with Ecology, the Idaho Department of Environmental Quality and the Spokane Tribe of Indians hired experts at Portland State University to conduct new computer modeling after the EPA changed its procedures in 2008. Instead of measuring “background” levels of phosphorus and other nutrients at the Idaho/Washington border, EPA reversed course and said background levels used should be from Lake Coeur d’Alene, miles upriver.
This change in course changed the numbers used to calculate how much phosphorus each industry and municipality along the river is allowed to discharge on both sides of the state line. Changes were made in the water quality improvement plan based on the new course, new computer modeling and two prior public comment opportunities in the past two years.
Water quality models are mathematical tools that are used to represent a water system. By entering all the data into a model, scientists can visualize, predict, and determine water quality factors that may be causing pollution. They can see what the river’s levels of phosphorus might be under different scenarios, and from there, good decisions can be made.
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