Sanitation Department mandates 24-hour pump tests for new subdivision wells

The Missoula County Commissioners' Public Meeting on May 29, 2025, focused on critical discussions regarding water availability and sanitation requirements for new developments. A key point of contention arose over the necessity of a 24-hour pump test for septic systems, as highlighted by Ms. Evans' comments.

One participant expressed concern that the current process may have changed, noting that typically, preliminary plat approval would precede detailed sanitation assessments handled by the sanitation department or the Department of Environmental Quality (DEQ). The speaker emphasized the importance of relying on scientific data rather than anecdotal evidence when assessing water levels and aquifer conditions.

The discussion included technical details about the testing of wells, particularly the need for wells to be inactive for 72 hours before measuring static water levels. This requirement is crucial for obtaining accurate data, as any recent use of the well could skew results. The speaker pointed out that previous aquifer tests conducted in 2007 had established a baseline for understanding water availability in the area.

The conversation also touched on the distinction between physical and legal water availability, particularly concerning exempt wells, which do not require proof of legal availability under certain conditions. The speaker clarified that while the project under discussion did not necessitate extensive testing, they would still gather data if sanitation regulations mandated a pump test.

In conclusion, the meeting underscored the complexities of water management in Missoula County, particularly as it relates to new developments and the need for accurate testing protocols. The outcome of the discussions may influence future regulations and the approval process for new subdivisions in the area.