Connelly & Associates, Inc. is a drilling contractor headquartered in Frederick, Maryland, providing geothermal loop-field drilling, water well installation, geotechnical exploration, environmental drilling, and sonic drilling across the Washington DC and Baltimore Mid-Atlantic region since 1991. The company operates one of the region's most capable drilling fleets, including sonic rigs, auger rigs, direct-push units, and limited-access equipment suited to both urban and remote sites. Connelly specializes in ground-loop installation for closed-loop geothermal systems, partnering with HVAC contractors on residential and commercial geothermal projects; it does not install heat pump equipment itself. All operations are conducted in compliance with OSHA and EPA standards, and the company's Maryland Master Water Well credential supports its well-drilling work.
Verified active operator per https://connellyandassociates.com/ + https://www.bbb.org/us/md/frederick/profile/drilling-contractor/connelly-assoc-0011-90137149 (Bundle 4 audit 2026-05-28)
One of the most advanced and diverse drilling fleets in the Mid-Atlantic with 30+ years of geothermal and geotechnical expertise, handling closed-loop installations and complex subsurface projects across the region.
