Aging infrastructure, tightening permit requirements, increased demand: these factors are driving capital needs for drinking water systems across the country. Communities are faced with the challenge of funding major upgrades to their treatment facilities with no easy way to pay for it. The Town of Cumberland, Rhode Island found a creative solution to this complex bundle of issues: develop a completely new water supply to eliminate the need for expensive treatment upgrades, increase resiliency to climate change impacts, and improve the quality of its drinking water.
Cumberland already used multiple sources for its water supply: surface water, ground water, and purchased water. Surface water was drawn from Sneech Pond, where Cumberland’s treatment facility, built in the 1950s, was struggling to keep up with increasingly strict permit and residuals discharge requirements. Meanwhile, growth was pushing demand for drinking water up, putting additional pressure on the facility, and it appeared that the town was facing a huge capital expenditure.
An innovative solution
Given the potential cost impacts, Woodard & Curran and Cumberland decided that switching to an entirely groundwater-based supply was the right choice. The returns realized from this approach are significant, not only in dollar terms but in additional resiliency to drought, severe weather, and source water quality changes.
To determine if this approach was feasible, Woodard & Curran performed engineering and hydrogeological assessments of potential groundwater source areas in town, including multiple site screening, selection, and soils and aquifer evaluations. Two sites were identified, at which we implemented small diameter test well programs and short and long-term pumping tests.
The data collected was used to obtain final regulatory approval to withdraw over 2 million gallons per day from two separate sites. Each includes two new gravel packed wells and associated pumps, chemical addition for pH adjustment and corrosion control, disinfection to provide 4-log virus inactivation, fluoridation, and a standby generator for emergency power. Telemetry is included for remote monitoring, alarming, and control, and will be incorporated into Cumberland’s existing Supervisory Control and Data Acquisition System.
The production rate from the new wells completely offsets the Town’s surface water treatment and purchased water needs, and the high-quality groundwater from the new well requires only chemical treatment. This means that Cumberland can decommission its surface water treatment plant. Instead of spending millions, the town avoid the entire cost of upgrading and running that facility. The annual cost savings will be in the hundreds of thousands of dollars and will allow the Town to recover the total project costs in just a few years. Over the life of the new supply, the expected savings are in the tens of millions.
One of the new facilities is located on an existing historical site and was designed with architectural details that blend the new facility and associated infrastructure into the historic structures. Woodard & Curran worked hand-in-hand with Cumberland to carry out an extensive public outreach campaign and engage with numerous stakeholders including the Department of Health, the State Historical Commission, a citizen’s oversight association, and the site’s abutters to develop a design that accommodated all of the competing concerns. The second facility is planned for completion in late 2022.
In addition to the financial benefits of the project, the new groundwater supply makes Cumberland more self-sufficient and creates a new high-quality supply that is more resilient to climate change. Not every community is able to make this change, but for those struggling with the escalating capital costs of aging surface water treatment facilities, it is worth a hard look. For Cumberland, this innovative approach is making a significant difference.
