Location (Water Treatment Plant)
4806 Highway 85
Williston, ND 58001
Jeff Bryson | Water Treatment Plant Production Superintendent
Location (Public Works)
1121 5th Street East
Williston, ND 58801
PO Box 2437
Williston, ND 58802-2437Dave Bell | Public Works Director
Kenny Bergstrom | Public Works Operation Manager
IMPROVED WATER TREATMENT FOR THE CITY OF WILLISTON & REGION
The upgrading improvements for the Williston Regional Water Treatment Plant started in the late 1990’s due to a combination of issues. The regulatory issues created by the federal government’s Clean Water Act and Safe Drinking Water Act were the driving forces for the upgrades along with the aging infrastructure and plant capacity needs.
The present plant was built originally in 1960 as part of a relocation project by the Corps of Engineers due to the creation of the Garrison Dam and its affects on Williston’s existing water treatment plant which at the time was located south of the Burlington Northern Railroad tracks and 6th Avenue West.
The new Federal Drinking Water Standards indicated to the city that the existing plant would have trouble meeting some of the proposed more stringent requirements. In particular, the turbidity and disinfections by-product rule regulations were not attainable by our treatment processes at the time.
The City initially asked for a consultant firm in 1998 to evaluate the capabilities of the water treatment plant to handle the City of Williston and its regional water users, Williams Rural Water District and Trenton Water Users Association, needs for the future. This master study was completed in 1999 and the first step in the master plan was Phase I, which dealt with filter upgrades that would help the plant meet current regulation. Costing approximately $4 million, this plant work began in 2001 and was completed in 2003. The filter upgrades were designed to meet the more stringent turbidity requirement by replacing the filter media, increasing the number of filter bays, and expanding its capacity to handle 10 million gallons a day. Around the same time the Phase I improvements were taking place; plans were reviewed for an upgraded transmission line from the water treatment plant to the City of Williston. An additional 30” iron transmission line was installed and fully complete by 2004. The additional water transmission line provided a safe guard to the regional water users by ensuring a safe quantity of potable water delivery to the city of Williston and the rural water pump stations by having a redundant water supply line. The new water transmission line cost $4 million and was partially funded by a $2 million State and Tribal Assistance Grant secured by our congressional delegates.
Construction on Phase II of the water treatment plant improvements began in 2005 and was completed in November 2006. This phase, with an estimated cost of $20 million, mainly focused on meeting clean drinking water standards for the disinfections by-products and adding to the plant’s capacity. The highlights of the Phase II improvements include two unique treatment processes that had never been implemented in other North Dakota water treatment facilities. They are ultraviolet (UV) light disinfections and a sedimentation removal process called ActiFlo. The UV light treatment is for water borne bacteria that is resistant to normal water treatment disinfections processes. The ActiFlo process eliminates the need for the larger pre-sedimentation basin and replaces it with a much smaller space treatment facility located within the plant expansion building.
An additional treatment upgrade was to switch from free chlorine to chloramines as the potable water disinfections process. This assists in reducing the amount of undesirable regulated disinfections by-products; mainly trihalomethanes. Also it is worthy to note that Phase II provided additional solid contacts basin (softening), raw water line, new chemical feed equipment and control center.
While the previous water treatment plant was capable of producing a little over 6 million gallon per day (MGD) the new plant can produce 10 MGD.
With all the improvements made from Phase I to Phase II, the area water supply, quality, quantity and reliability has been much improved since the late 1990’s.
The funding for the $28 million dollar plus improvements over the years has come from a mixture of funding sources. The City of Williston utilized approximately $3.5 million dollars of city sale tax dollars and water user’s rates increases of approximately $1.40/unit (750 gallons). There was the $2 million state and tribal assistance grant and a $5 million grant from the MR&I funds distributed to the state by the Federal Dakota Water Resource Act.