Beaver Lake algae-test limits would be state 1st

Agency starts push to protect drinkability

— A drinking-water source for about 420,000 people in Northwest Arkansas would become the first body of water in the state to have numeric limits on indicators of algae growth under a proposed update of the state’s water-quality standards.

The limits on chlorophyll a and Secchi transparency, both measures of algae growth, in Beaver Lake are among the changes in a draft update of the standards that the state Department of Environmental Quality presented to the state Pollution Control and Ecology Commission on Friday.

At its meeting in North Little Rock, the commission approved a request by the department to begin the procedures for adopting the revised standards, known as Regulation 2.

The commission’s action starts the clock on a public comment period on the revisions that will end at 4:30 p.m. May 8. Public hearings on the proposed changes are tentatively planned in April in Jonesboro, Fayetteville, El Dorado and North Little Rock.

The Environmental Quality Department developed the proposed nutrient-pollution standards for Beaver Lake through a two-year study paid for in part by a$143,000 grant from the federal Environmental Protection Agency and an $85,000 grant from the Walton Family Foundation.

The lake and other water bodies are now protected by a “narrative standard” on nutrient pollution, which has no numeric limits.

According to the narrative standard, materials “stimulating algal growth shall not be present in concentrations sufficient to cause objectionable algal densities or other nuisance aquatic vegetation or otherwise impair any designated use of the water body.”

The proposed standard for Beaver Lake would limit chlorophyll a, an algae pigment essential to photosynthesis and algal growth, to 8 parts per billion.

It would establish a minimum Secchi transparency of 1.1 meter, or just over 3 1/2 feet. The measurement is the depth at which a black-and white disk lowered into the water disappears from view.

The standard specifies that the chlorophyll and transparency readings would be taken at a particular point on the lake below the confluence of War Eagle Creek and the White River.

Bob Morgan, environmental quality manager for the Beaver Water District, said the standards are meant to prevent algae from having major effects on the taste and smell of drinking water.

Although the lake would meet the proposed standards, algae already causes taste and odor problems for six to eight weeks every fall, Morgan said.

“I’d say we have moderate problems, not severe problems so far,” said Morgan, who served on an advisory group that helped develop the standards.

Although no numeric standard has been set for Lake Maumelle in central Arkansas, the prevention of pollution from phosphorus and nitrogen, both of which stimulate algae growth, is a goal of a proposed zoning code that would restrict development in the lake’s watershed. The Pulaski County Quorum Court is set to vote on the code Tuesday.

Randy Easley, director of water quality for Central Arkansas Water, which owns the lake, said algae has caused occasional taste and odor problems for the lake water, but not as severe as the problems in Beaver Lake.

“Right now, we’re in good shape,” he said.

Steve Drown, chief of the state department’s Water Division, said the department plans to eventually establish numeric nutrient pollution standards for other lakes and streams in the state.

The EPA has encouraged states to develop the standards as part of a nationwide initiative to curb pollution that stimulates algae growth, he said.

“Nutrients are the most common impairment that some of these states are seeing,” Drown said.

The standards for Beaver Lake could potentially affect Fayetteville, Huntsville and West Fork, which discharge treated wastewater into tributaries of the lake.

If a water body fails to meet standards, it can be declared impaired, resulting in tighter restrictions on the amount of pollution cities, companies and other entities are allowed to discharge into the water body and its tributaries.

Morgan said the amount of wastewater discharged into the Beaver Lake watershed would have to “grow significantly” to put the lake in violation of the proposed nutrient standards.

Storm-water runoff also contributes to the nutrients in the lake, he said.

“For the last 10 years, we haven’t seen a lot of change, but that could change with land use,” he said.

The proposed revisions are the result of a triennial review required by the EPA.

Unlike the proposed Beaver Lake standard, most of the 163 proposed revisions to the 162-page document clarify wording but don’t change the existing standards, Drown said.

One change would remove standards, adopted in 2007, that increased the limits on chloride, sulfate and total dissolved solids in several streams in the Ouachita River basin.

The increases were adopted at the request of El Dorado Chemical Co., Great Lakes Chemical Co. and Lion Oil, which discharge wastewater into the streams, but they were rejected by the EPA.

After the public comment period, the revised water quality standards will go to the state Legislature for review before returning to the commission for final approval.

Front Section, Pages 1 on 02/23/2013

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