For the more than 15 million households who use private well water as their drinking water, making sure it is safe to drink is a big concern. Unlike municipal water users, private well owners take on that responsibility without help. It has been hard for the owners to get outside help with managing their well water quality. A team at Northeastern University is working to close the knowledge gap.

Private Well Owners Are On Their Own

Municipal water systems are treated and tested regularly. Users of this water can rest easy knowing that problems, for the most part, are detected and fixed before they become an issue for the user.

Private wells have to be monitored by the owner and there are few regulations around private wells.

Often owners don’t know when they should test. According to the EPA, you should test annually at a minimum. They recommend testing more often if you have vulnerable people, e.g., kids, elderly, etc., using the well water.

They also recommend testing right away if you hear about other private well owners having issues in your area, you change any part of the well system, you notice a change in odor, color, or taste, or there is a major event like a flood or new construction near the well.

This leaves them with little data to guide them on testing and treatment and puts them at risk of health problems from water contamination.

This is especially problematic when floods happen, like the one from Hurricane Harvey in 2017. This hurricane flooded the U.S. Gulf Coast and wells along the coast started testing for higher levels of fecal bacteria. A team from Northeastern University found that in 9,000 wells tested there were 2.8 and 1.5 times higher levels of Escherichia coli and total coliform post hurricane.

After events like this, the owner often doesn’t know that they should test their wells. The best way for well owners to see if the well water needs to be tested is by contacting local experts, like health department officials.

They can also check the local papers for construction projects, attend hearings and ask questions about the impact to their well water, and read through environmental impact statements. This is a lot of effort for a private well owner and often isn’t done.

Monitoring Well Water Risks Using Remote Sensing

A group of researchers at Northeastern University is combining remote sensing data, census demographics, flood hazard maps, and well water sampling data to help fill this information gap.

At last estimate there were around 44 million people using private wells. A Virginian study tested a large number of wells and found that up to 60% had levels of contaminants that could impact the user’s health.

There is very little data on well use and ownership. The last census on private wells was in 1990. Without this information, there is little that can be done to assist well owners after a natural disaster.

The Northeastern team’s project addresses this by identifying where flooding has happened using remote sensing data and comparing that with satellite and census data to pinpoint which private wells might be impacted.

One big barrier will be scaling down remote sensing data to the household level. Typically, the data is at a huge scale. The team is still working on how to do this.