This op-ed originally ran in the Baltimore Sun and was co-authored with Maryland Del. Vaughn Stewart (D-Montgomery County).

If you’re one of roughly 2 million Marylanders whose drinking water comes from a private well, you or your property owner is responsible for maintaining the well and ensuring its water is safe — no exceptions. That’s because federal clean water laws don’t cover private wells or small water systems, and state-level protections vary dramatically. In Maryland, those protections are few and far between.

In a recent Center for Progressive Reform (CPR) report on state-level efforts to protect private well owners, Maryland ranked among the five states with the fewest protections. Unlike other states, Maryland doesn’t offer well owners free or low-cost water testing kits or require water quality test results be disclosed during property sales. While the state does require new wells to meet certain safety thresholds, this policy falls short because it doesn’t ensure that well water will stay safe over time.

One key well water contaminant: nitrates. Nitrates form when nitrogen breaks down, and they can pollute groundwater when fertilizer or manure is mismanaged or over-applied to fields. Since they are odorless, colorless and tasteless …