City hears water-supply plan: wells and storage adequate through 2035, drought named primary risk

City water officials and consultants presented the Water Supply Service Area Plan (required under Wisconsin—s NR 854) at the Oct. 22 council meeting, concluding the Fond du Lac Water Works has adequate deep-well capacity and storage to meet projected demand through 2035 but should monitor aquifer conditions and plan options if demands approach aquifer capacity.

Steve Kliesner of Strand Associates, who led the study, said the system—s total well capacity exceeds 9,000 gallons per minute (firm capacity roughly 7,000 gpm) and total storage approaches 10 million gallons (about two average days of storage). He summarized previous aquifer analyses indicating the North Well Field capacity at roughly 4—6 million gallons per day (MGD) and the South Well Field at roughly 2—3 MGD (combined estimated range approximately 6—8 MGD).

Kliesner said projected average-day demands in the plan are about 4.6—.9 MGD through the planning period, with maximum-day demands reaching the 8 MGD range. "Your aquifer capacity is greater than your average day demand, which means you have adequate aquifer supply over the planning period," he said, while noting that maximum-day pumping can stress individual well fields and require operational balancing.

The presentation noted a storage surplus of approximately 3.6 million gallons and identified three principal source options should supply approach capacity in the future: additional deep wells (including a previously studied east-side well field), shallow wells (not recommended due to capacity limits) and surface water from Lake Winnebago (technically viable but requiring more treatment and distribution changes). Kliesner said the most practical near-term option from a cost and operations perspective is an additional deep well field.

During Q&A, council members asked about aquifer stability and threats; consultants cited drought as the primary short-term risk to supply and said ongoing monitoring of pumping water levels and proactive well maintenance were critical to managing that risk.

The city will complete the water-supply service area plan as required by NR 854 and incorporate it into future planning; a more detailed water-system plan will follow to identify capital projects, replacements and distribution improvements.