The city of Auburn says proposed ordinances changes impacting Lake Auburn’s water quality are backed by a new assessment. The city’s announcement comes amidst a lawsuit from a neighboring municipality.

In a press release, Auburn states it wants to limit density in areas around the lake and incorporate "best practices in phosphorus control and subsurface wastewater disposal in the Lake Auburn Watershed."

More information about the assessment will be presented to the city council on Monday.

The work follows up on an analysis that FB Environmental conducted in 2021. 

According to FBE, although the changes result in improvement in water quality over a "do nothing different" scenario, the city's - and its partners' - work to protect Lake Auburn is not done, according to the release.

Lake Auburn's water quality is at the center of a suit filed by the neighboring city of Lewiston in June against Auburn.

At issue are Auburn's efforts to exclude a 148-acre parcel from the watershed and a proposed change to its ordinances regarding residential septic systems that would make it easier to build new housing along the lake.

Lewiston does not share a border on the 15-square-mile lake. However, Lake Auburn is the drinking water source for both cities.

Lewiston's suit maintains Auburn's ordinance changes would harm water quality and may impact an EPA waiver in effect since the 1990s. Violating the waiver could result in the need for a new filtration system that would cost both cities millions of dollars.

Lake Auburn cannot be protected without the cooperation of other municipalities within the Lake Auburn Watershed implementing similar measures to control phosphorus, according to the city, which cited FB Environmental's analysis.

"Auburn staff look forward to working with the Auburn Water District and Lake Auburn

Watershed Protection Commission during review of phosphorus control plans and updating of

the watershed base plan through a public process," the release stated.

Phosphorus is a naturally occurring mineral and is frequently found in fertilizers and manure. Too much phosphorus in a body of water can deplete oxygen and result in recurring algae blooms. The decayed algae following a bloom can result in areas where there is no oxygen, which can kill fish.