Business Details
36 Years
experience
Your Trusted Excavation & Septic Contractor in Marlborough, NH
David O'Neil Construction has served Southern New Hampshire and the Monadnock Region for over two decades, specializing in excavation and septic system solutions. With a combined 40+ years of industry experience in excavation and carpentry, our team delivers safe, cost-effective projects ranging from septic installations to driveway repairs and drainage systems. We maintain full licensing and insurance, operating a fleet of professional equipment including excavators, dump trucks, and backhoes. Our approach prioritizes client collaboration, transparent communication, and utilizing local soil scientists for precise septic system designs.Backed by decades of hands-on experience and hundreds of completed projects, we ensure compliance with NH state regulations while providing maintenance guidance for long-term system viability. Our commitment to quality materials, precise installation, and customer education has earned consistent positive feedback from residential and commercial clients requiring excavation, septic services, and site work solutions.
Services
Septic System Installation
Video Camera Inspections
Excavation Services
Drainage Solutions
Driveway Repairs
Septic Tank Pumping
French Drain Installation
House Lot Development
Underground Utility Installation
Emergency Excavation Services
Details
- Year established: 1990
Highlights and features
- 20+ years of combined excavation and septic system expertise
- Fully licensed and insured New Hampshire excavation contractor
- Comprehensive services from design to installation and maintenance
- Client-focused process with transparent cost estimates
- Modern equipment including mini excavators and video inspection technology
What people say
Top notch service
Excellent work
Professional and timely
Dependable team
Great communication
Services
Septic System Installation
We design and install code-compliant septic systems using local soil scientists and approved plans. Our process includes test pit analysis, system layout, tank installation, and Enviro-Septic technology options. We coordinate permitting and ensure proper drainage with sand fill and hydroseeding for lasting performance.
Video Camera Inspections
Our video inspection technology identifies issues in septic tanks, distribution boxes, and leach fields. Using camera locator technology, we map underground components and provide detailed reports. This service helps buyers evaluate systems pre-purchase or diagnose existing system problems with precision.
Excavation Services
We handle residential and commercial excavation projects including foundation digging, utility installation, and site preparation. Our equipment fleet supports projects from small repairs to large-scale development, with attention to proper drainage and soil management for long-term stability.
Drainage Solutions
Our drainage experts install French drains, foundation drains, and surface water management systems. We use durable materials like rubber lining and perforated piping to prevent basement flooding and manage runoff. Custom solutions address specific property water challenges effectively.
Driveway Repairs
We repair and install driveways with proper base preparation and drainage considerations. Services include grading, drainage solutions, and material recommendations. Our approach extends driveway lifespan through proper crown formation and compacted base layers for New England weather conditions.
Questions
What septic inspection services do you offer?
We provide comprehensive video camera inspections for septic systems and private sewer lines, including tank, distribution box, and leach field evaluations. Reports are emailed within 48 business hours.
How much do septic system installations cost?
New septic systems typically range from $20,000 to $30,000 depending on system type, soil conditions, and site requirements. We provide detailed estimates after design approval.
Do you handle drainage problems?
We install various drainage solutions including French drains, foundation drains, and underground drainage systems to prevent water intrusion and manage runoff.
What excavation services are available?
Our services include septic system installation, driveway construction, house lot development, underground utility installation, and emergency excavation with equipment available for projects of all sizes.
Are services available in winter?
Yes, we provide winter services including snow plowing, sanding, and emergency excavation. Equipment and crews remain operational year-round for urgent needs.
Reviews (6)
Brad Grinstead
Jun 16, 2018
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They are almost too good to be true. Honest, fair, and dependable. Dont waste your time (and money) on other contractors for your septic/leach field needs, or for all of the other services they provide.
Priscilla Leed
Nov 27, 2017
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David and his crew were very helpful in updating our forty+ year old system. Our need was urgent and they got a new system installed quickly. We expect it to last a long time. Thanks for a job well done!
Donna Sprague
Nov 19, 2017
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Two years ago, the septic system at my lakeside home desperately needed to be modernized. David came to evaluate conditions, called in an engineer to design the proper system, and followed up with all required permits and inspections throughout the process. He and his son performed all the site work, including removal of a paved driveway which had delivered excess rainwater and snow melt-off into my basement for years (that project uncovered an additional ancient septic tank!) Matt recommended recycled asphalt for the new driveway surface, which is permeable and friendlier to the environment near
Russell White
Aug 19, 2017
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With a dead line for sale of our house, it became painfully clear the septic system would not hold up. O'Neil not only put a rush on the job for us, but also did a very professional job at a competitive price.
Janelle Hodgman
Jun 14, 2017
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From a customer we met at the Home Show last year who needed work on their driveway.
"Pat and I would rate O'Neil Construction 10 on a scale of 1-10 with 10 being excellent. We had our driveway regraded with more drainage along the sides and pipes placed under the driveway where water could be diverted. A good base of gravel was put down with a top layer of SurePac on top . The estimate was well detailed listing exactly what would be done. The estimate was discussed with Pat and I and explained well answering all of our questions. They were prompt in the estimate and when they came to do the job
"Pat and I would rate O'Neil Construction 10 on a scale of 1-10 with 10 being excellent. We had our driveway regraded with more drainage along the sides and pipes placed under the driveway where water could be diverted. A good base of gravel was put down with a top layer of SurePac on top . The estimate was well detailed listing exactly what would be done. The estimate was discussed with Pat and I and explained well answering all of our questions. They were prompt in the estimate and when they came to do the job
Maria Coviello
Jun 14, 2017
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We used David O'Neil Construction for several projects and were very pleased with the professional way he did each project, priced fairly and done in a timely fashion. One of the projects that we cannot thank him enough for is his consultation and working on stopping water from coming in our property. He installed the perfect drainage to keep the property from water seeping in from every rainstorm.
Maria Coviello
Harisville Inn
Maria Coviello
Harisville Inn
