Water Filtration and Well Pump Specialists in Darnestown, MD

From Water Testing to Water Treatment, We Set the Home Standard for Quality 

Our Store

14111 Seneca Road
Darnestown, MD 20874



Monday – Thursday: 7am – 5pm

Friday: 7am – 4pm

Saturday and Sunday: 7am – 5pm

Currently closed due to COVID-19


Contact Information

T:  (410) 379-1993
F:  (301) 854-1538
E:  info@nationalwaterservice.com

Contact Us Today!


Give us a call or fill out our online form to get started

National water service employees trenchingWater is essential for your family’s home and health — your shower, bathroom, kitchen, coffee, and meals all depend on a healthy, functioning water system. Whether you’re purchasing a new building or need to update a current system, we have the experience you need to keep your systems functioning. 


Imagine not knowing the quality of the water coming from your sinks, dealing with a lack of water filtration, or being unable to replace your well pump. When these things happen to you, don’t worry, that’s what National Water Service is here to do.


For over 40 years we’ve been in the Darnestown local community giving free basic water analysis, setting the standard for water purification, and taking on projects big and small. From water storage to flood prevention, we’re here to assist you. 


With a master plumber, we are able to provide you with all of your water services in one place, gaining you a team you can count on for any room in your house. It’s pretty simple: when the water needs serviced, we do it all, with reliability you can count on.

Residential Water Care, for Your Family’s Well-Being

National Water service workers working on a wellAs a homeowner, your top priority is the water flowing through your pipes. Whether you are on city water or a well system, the water quality can vary from neighborhood to neighborhood, and it serves you best to have that water tested before you come across any surprises.


Our basic analysis is free, with extensive testing offered at a reasonable rate for any contaminant that may be suspected. If you’re the do-it-yourself kind of person, don’t worry, all our work is neat and tidy, making the simple tasks like changing a filter or adding a solution tank a breeze for you. 


Additionally, we utilize non-proprietary systems for handling problems. These water treatment systems generally cost less and rarely become obsolete, meaning you save money and have long-term system confidence. 

Commercial Water Services, At Your Doorstep

Commercial water serviceNational Water Service has the capabilities to handle your commercial water needs, satisfaction guaranteed.


Water treatment and testing, well pumps, flood prevention systems, and water storage including low yield wells and irrigation storage are all available to you when you work with our team of specialists. 


Our friendly staff is able to provide pumps, tanks, and boosters; crane services; and trenching, all for your business needs.


We’re experienced with business offices and food services alike, even offering reverse osmosis for a selection of varying different issues. It’s all covered when you call National Water Service, here to keep you up and running, worry-free.

All Around Emergency Water Services

Water service, residence water breakWater contaminant concerns can be worrisome, but with the right team, anything can be handled.


We offer specific, in-depth testing for Radon, Lead, Nitrate, Bacteria, E Coli, Coliform, Pharmaceuticals and much more. If your basic analysis doesn’t come back right, we’re here to work with you until the issue is resolved.


National Water Service also offers you seven-day-a-week emergency services, so you don’t know need to fret when something breaks on a Sunday, because we know accidents happen and can’t wait till Monday.

We Have the Water Filtration System for You, Darnestown

Clean water service projectOur friendly staff is still servicing the same systems we installed over 30 years ago, because our clients value our trust, dedication, and workmanship.


We service you with the best tools for efficient care, including well cameras, underground line finders, and pump hoists. And when our clients speak, we listen, that’s why we now employ a plumber for all your needs.


It is our dedication to your service that allows us to re-do your kitchen or bath, install new gas lines for generators and outdoor grills, and repair your water heater. Call us today to discuss our new client discounts and how any home or commercial need is available to you.

Contact Us Today!


Give us a call or fill out our online form to get started