City of Lake Lillian

The City of Lake Lillian, a small city in Kandiyohi County, Minnesota, faced significant challenges due to its aging infrastructure, which led to critical water and sanitary issues posing health and safety risks to residents. Ongoing problems with drinking water quality (including arsenic levels more than 2.5 times above the allowable limit) made it clear that immediate action was needed. In 2017, the City partnered with Bollig Engineering to develop a multi-phase municipal infrastructure improvement plan designed not only to resolve current issues, but also to build a stronger, safer foundation for the future.

Lake Lillian Infrastructure Improvements

Phase 1 – Utility and Downtown Revitalization

• Replaced failing watermain, sanitary sewer crossing, and storm sewer piping.

• Coordinated with Kandiyohi County’s CSAH 8 road reconstruction.

• Enabled the City’s vision for a more walkable, welcoming business district with wider sidewalks, added green space, and decorative lighting.

Phase 2 – Lift Station & Meter Upgrades

• Replaced the community’s lift station.

• Installed new water meters to improve the efficiency and reliability of service.

Phase 3 – Advanced Water Treatment Plant Improvements

In 2021, Lake Lillian launched a pilot project to address periodic taste and odor complaints, as well as high levels of ammonia, iron, and arsenic in its groundwater supply. To bring additional expertise, Bollig partnered with subconsultant AE2S, a premier provider of water and wastewater engineering services in the Upper Midwest, to test innovative biological treatment methods. This process uses naturally occurring microorganisms to treat water through oxidation and nitrification. The pilot demonstrated that more than 95% of the raw water ammonia could be removed while still meeting treatment objectives for iron and arsenic.

The success of the pilot made Lake Lillian one of the first small communities in Minnesota to adopt full-scale biological drinking water treatment. The upgraded facility reduces chemical costs for chlorine and permanganate, while providing safer, better-tasting drinking water. Bollig and AE2S designed the new water treatment plant, which now ensures reliable water quality for the community.

Phase 4 & 4a – In Progress

• Replacement of aging cast iron watermains and clay sanitary sewer pipes.

• Stormwater system improvements and street reconstruction.

• Construction is currently underway, with additional funding efforts ongoing.

Lake Lillian Project Impact

• Safer, Cleaner Drinking Water: Consistent compliance with Minnesota water quality standards and improved taste and reliability.

• Community Vitality: A revitalized downtown district with enhanced walkability and aesthetics.

• Long-Term Reliability: Modernized water, sewer, and stormwater systems that reduce risk of failures and ensure service for decades.

• Financial Stewardship: Leveraged $13.2 million in state and federal infrastructure funding to minimize the local financial burden.

• Transparent Process: Public meetings and environmental reports kept residents engaged and informed.

If your small city is facing challenges with drinking water quality, sewer infrastructure, or stormwater management, this Lake Lillian, Minnesota case study shows how phased planning, innovative treatment technology, and expert funding strategies can transform critical infrastructure.