Asset Management – Williston ND Wastewater System Outgrowth

Williston, North Dakota has a growing population affecting its sewage lagoon system capacity to handle the excess wastewater.

There are major concerns that this issue will have a negative effect on the backwaters of the Missouri River and the headwaters of Lake Sakakawea.

Most of the immediate concern has occurred due to a marsh area where Williston discharges 19 million gallons of treated wastewater each week containing enough ammonia to be extremely toxic to fish.

Six fish die-offs were reported this year, and conservationists are concerned about the long-term impact the treated wastewater will have on the environment.

The Bismark Tribune reports:

“Steps the city has taken in response to the demand include adding chemicals to the water and more aeration equipment to speed up the treatment process, Tuan said.

The city also spent $7.5 million on a temporary plant while the new wastewater treatment plant was being developed, he said. But the temporary plant has not worked out as intended.

That facility includes a pipeline allowing the city to release treated wastewater directly into the backwaters of Missouri without having an impact on the marsh.

The pipeline was used for a short time but has been offline since May 2014 after a fish kill in the discharge area.

The North Dakota Department of Health, which regulates the city’s wastewater discharges, issued Williston a notice of apparent noncompliance and attributed the fish kill to a lack of ammonia treatment in the city’s wastewater.

“We feel that was definitely related to their wastewater discharge,” said Karl Rockeman, director of the Division of Water Quality.

After that incident, the city and the state health department decided together that the temporary plant was providing even less ammonia treatment and discharging through the marsh was the “least damaging option,” Rockeman said.

The equipment in the plant is still being used but not to the level it was intended, Tuan said, and it will be incorporated into the permanent wastewater plant.”

The city is constructing a new wastewater treatment facility due to be completed this fall which will hopefully help to cut the amount of wastewater being discharged, therefore reducing the ammonia levels, but at this point results are uncertain.

Inframanage.com notes that wastewater treatment plants can be major expenditure items in your wastewater network asset management plan – both capital expenditure, and ongoing operations and maintenance.

When thinking about wastewater treatment plants it is important to consider what are the drivers for the timing and type of upgrade required.

This will then allow projection of upgrade cycles and subsequent capital, operation and maintenance expenditure requirements.

Wastewater treatment plants are definitely an asset class that benefits from optimizing the asset life cycle management through the life of the asset.

PHOTO CREDIT: Andrew Filer via Flickr Creative Commons License. The photo has been cropped to fit website requirements.