St. Mary’s County Health Department (SMCHD) is suspending wet season perc testing effective Friday, April 17, 2026. The suspension is due to declining groundwater levels, made clear by observing conditions within a network of monitoring wells in the county.

All perc test applications that were not scheduled and evaluated will be prioritized for scheduling when groundwater levels are adequate for the next wet season, expected in 2027. Applicants may also request a refund; however, they must then reapply when the wet season returns and will lose their place/priority for scheduling during the next perc testing season.

For more information, please contact the SMCHD Environmental Health Division at (301) 475-4321.

For additional information on perc testing, please visit smchd.org/perc-testing.