August 27 2010

Al Edenloff, Published August 27 2010

Sewage in, clean water out

It’s a dirty job but someone has to do it. And the Alexandria Lake Area Sanitary District (ALASD) has been doing it – treating and disposing sewage – since October 1, 1977.

On Wednesday, it held an open house to let the public know more about its efforts to restore water for a healthier, natural environment.

The ALASD was created by an act of the Minnesota State Legislature in 1971.

Local units of government that are ALASD members include the city of Alexandria and the townships of Alexandria, Carlos, Hudson, Ida, LaGrand and Lake Mary.

The facility, located near Nevada Street in West Alexandria, treats about 2.5 million gallons of wastewater a day.

Another 916 dry tons are treated annually and recycled onto agricultural land in accordance with state and federal regulations.

Just how clean is the treated wastewater when it leaves the treatment facility?

Believe it or not, the treated water, which is drained into Lake Winona, is nearly safe enough to drink, according to the ALASD.

It gets kind of technical but, according to the ALASD, the removal efficiency of “biological oxygen demand” and “total suspended solids” exceeds 98 percent and the total phosphorous removed exceeds 96 percent.

So for the most part, the treated wastewater effluent meets state and federal drinking water standards, with the exception of sulfate or salt concentrations and fecal coliform. The coliform meets standards when heavy disinfection is implemented.

The wastewater effluent also meets permit limits established by the Environmental Protection Agency and the Minnesota Pollution Control Agency.