The City of Longview and the Beacon Hill Water & Sewer District (BHWSD) currently supply customers with drinking water sourced from groundwater wells and treated at the Mint Farm Regional Water Treatment Plant. Mint Farm reliably produces drinking water that meets all regulatory standards. But when a 2014 survey found that a large majority of water customers were unsatisfied with their water, the City and BHWSD undertook a study of water quality improvement options. The study, completed between 2014 and early 2016, considered more than 50 different options to modify the water supply and improve water quality. Switching the water source from Mint Farm groundwater wells to Cowlitz River riverbed collector wells was initially identified as a preferred alternative. However, disappointing water quality testing results caused this approach to be removed from consideration in July 2016. (Find out more about the study here.)
The City and BHWSD are currently looking into treatment modifications at Mint Farm that may improve water quality and address some of the issues that have concerned customers. Later this year, staff will recommend next steps to address taste and odor complaints and propose methods to evaluate treatment options for silica removal.
Early this year, four sites along the Cowlitz River were explored to investigate horizontal collector wells as a source of water to replace the Mint Farm aquifer. Initially, three sites were tested but less than desirable results prompted consideration of a fourth site. In the end, two sites proved feasible in regards to capacity but water quality testing showed high levels of iron, manganese, hardness and silica (download water quality test results and comparison, PDF 128 kb), the same constituents which are the cause of many of the current customer complaints.
Water quality may improve over time, with high-volume, long-term pumping eventually displacing groundwater and drawing more water from the Cowlitz River. However, the degree and rate of change is unknown and would require additional investment and testing to prove or disprove it.
The next steps of testing would involve drilling a larger test well, multiple observation wells and ongoing water quality tests. The technical consultant provided two testing options ranging in cost between $180,000 and 435,500.
The decision facing the City Council and BHWSD Commissioners was whether to approve this additional testing or cease further investigation.
In a special joint meeting on July 28, City Council and BHWSD Commissioners decided to cease further investigation of collector wells and reconsider Mint Farm improvement options. Later this year, staff will recommend next steps to address taste and odor complaints and propose methods to evaluate treatment options for silica removal. Download a schedule of work.
The effort to return to the Cowlitz River for Longview’s drinking water supply is dead.
Longview council members and Beacon Hill Water and Sewer District commissioners unanimously agreed Thursday to halt testing for a Ranney collector well system.
The vote follows months of discouraging water quality testing of potential Cowlitz River Ranney locations. Silica and iron concentrations were far higher than at the Mint Farm artesian well system.
Longview and Beacon Hill officials said they want to pursue a staff-recommended plan to improve the taste and odor problems with water from the Mint Farm well system.
A special joint meeting of the City Council and the Beacon Hill Water & Sewer District Commission is scheduled for July 28. The purpose of the meeting will be to review the Phase 1 study results of potential collector well sites and determine what the next steps should be. Engineering information, water quality test data, and additional pumping cost proposals will be presented during the meeting.
The joint meeting will directly follow the regularly scheduled council meeting. The joint meeting will likely begin around 8 p.m. All are welcome to attend.
Meeting to review potential collector well study results and determine next steps
Date: July 28, 2016
Location: Council Chambers, Longview City Hall, 1525 Broadway, Longview
Time: Regular Council meeting will begin at 7 p.m. Special joint meeting will follow, likely beginning around 8 p.m.