When was the last time you visited your doctor for a regular check-up? Maybe annually, perhaps even twice a year if you’re diligent. Now, consider this: your drinking water gets checked hundreds, even thousands, of times every single month.

Public Water Systems across Massachusetts quietly carry out a surprisingly large number of routine analytical tests to ensure your water meets or surpasses the stringent standards of the Safe Drinking Water Act. These aren’t random or occasional tests — they are a continuous, rigorous process designed to protect public health.

Each month, your local water professionals test for contaminants including bacteria, nitrates, heavy metals like lead and copper, disinfection by-products, pesticides, and many others. Systems also measure disinfectant within their treatment plants and distribution systems to ensure protection from bacteria and viruses. The frequency and type of contaminant monitoring is mandated by the state and adhered to by the system. The frequency of these tests can range from daily to monthly, quarterly, or annually, depending on the size of your community, the source of your water, and the type of treatment provided. In a single month, even smaller water systems can perform hundreds of individual tests, while larger systems can conduct thousands. Monthly, these test results are forwarded to our state regulator, the Massachusetts Department of Environmental Protection. Water systems often supplement their routine sampling with online continuous monitoring to be able to view real-time water quality trends and then respond to any potential alarms.

Why such rigorous oversight? Because Public Water Systems are your water’s frontline healthcare workers — conducting constant check-ups to catch potential issues before they become problems in order to protect the people they serve. So unlike with your annual physical, your Public Water System doesn’t have the luxury of waiting a year to find out if something is wrong.

Water quality doesn’t happen by accident. Behind every drop from your faucet is a network of dedicated, trained, and licensed professionals working around the clock, meticulously testing, monitoring, responding, and maintaining the infrastructure that delivers clean, safe water.

Next time you take a sip, remember: your water health check-ups never stop. Ensuring your water is safe isn’t a once-a-year event, it’s an everyday commitment. National Drinking Water Week (May 4-10) is a good time to appreciate all the unsung heroes in our water utilities who ensure the tap water that you and your family rely on every day is safe to drink. Take a moment this week to thank them for all they do!

Jennifer Pederson is executive director of the Massachusetts Water Works Association.