AUGUSTA — Gov. Janet Mills signed a bill into law Tuesday updating septic system regulations aiming to safeguard Maine’s lakes and ponds, according to a news release by the Natural Resources Council of Maine.

The new law, LD 1550 sponsored by Sen. Henry Ingwersen, D-York, addresses “short circuiting” in systems on properties abutting freshwater bodies such as lakes and ponds, the release said. Short circuiting occurs when septic system effluent skirts natural filtration processes by draining quickly through sandy soils or along shallow bedrock and into water bodies.

Maine Department of Health and Human Services will be required to revise design standards for septic fields in high-risk soil profiles only which address nutrient pollution through natural soil processes, according to the release. High-risk soil profiles include coarse sand, gravel and fractured bedrock. Maine’s subsurface wastewater rules include design and permitting standards that do not account for nutrient removal in these types of soils, a gap the new law is designed to fill.

Ingwersen was not immediately available to comment on what new design elements and permitting may look like when Maine Department of Health and Human Services finalizes its new rules.

Proponents of the new law identified the bill as an immediate and tangible way to curb freshwater pollution throughout the state.

“There are many aspects of lake health that are out of our hands, but managing septic systems is entirely within reach,” said Susan Gallo, executive director of Maine Lakes. “This new law protects Maine’s lakes and ponds, and the wildlife and people who use them, by ensuring that future septic systems are constructed to reduce both pathogen and nutrient flow into lake water.”

The new law, passed with bipartisan support in the House and Senate, guarantees existing land deemed suitable for a septic system will remain eligible for development.

“Poorly performing septic systems are a significant threat to Maine’s clean water,” said Luke Frankel, staff scientist for Natural Resources Council of Maine. “This new law will curb pollution by improving the design standards for septic systems in sandy soils next to lakes and ponds to ensure wastewater is properly treated.”