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Find Septic system installers and replacers in Merrimack

Avatar for Septic Designs of NH, LLC
Septic Designs of NH, LLC
4.5(
29
)

Serving Merrimack, NH and surrounding areas

Approved

In business since 2007

Free estimates

Emergency services offered

"They came to inspect the Septic for home buying .They explain the system and how it works ,so I could understand , showing me the cleanout and D Box area . After this they coverd the two holes and left it like they found it. They both are Pro s and I will use them again"
Septic Inspection
Leach Field
Septic System Distribution Box
Septic Camera
Septic Pipe

+43

Response time8 hrs
14 neighbors recently requested a quote
Recommended by96%of homeowners
Avatar for Innovative Septic Solutions
Innovative Septic Solutions
4.3(
34
)

Serving Merrimack, NH and surrounding areas

Approved

Super Service Award Winner

In business since 1985

Free estimates

Emergency services offered

"No one wants to replace their septic system, but if you need to â ¦. Call Bob. From begging to the end of the job, he made the process painless. He explained everything, how the system works and gave us options to fix the old system or replace. His crew was great, arrived when he said they would, worked quickly and left my yard/lawn in better condition then before the work started. Great company , great serviceâ ¦. Thank you!"
Response time2 days
8 neighbors recently requested a quote
Recommended by77%of homeowners
Avatar for Sewer Surgeons LLC
Sewer Surgeons LLC
5.0(
8
)

Serving Merrimack, NH and surrounding areas

Approved

In business since 2013

Free estimates

Emergency services offered

We pride our company on reliability, great communication, \nintegrity, and quality work. We are experts in our trade and will do our best \nto keep you as educated as we can on your particular task or project. We are locally owned and operated. Give us a call today, we look forward to earning your business!\n

Septic Repairs
Septic Repairs
Septic Repairs
4 neighbors recently requested a quote
Tom Howe Septic Systems and Excavation
4.9(
7
)

Serving Merrimack, NH and surrounding areas

Approved

In business since 1968

Free estimates

Customers say: Quick response

"Tom Howe and his team are a dedicated professional who takes his work very serious and it shows. A man of great integrity, Tom can sell you more but he won't. He will only sell you what you need. As a real estate agent, I see septic systems on a regular basis that have been poorly installed and failed inspections after just a few years. I have never seen a system that Howe has done that has failed. He only uses the best techniques and products so he can put his name and reputation behind them. As for my personal experience, Tom put a system in at my home and did so quickly and efficiently with no delays or excuses and it looked terrific when it was done despite the mounded look which he was very clever at blending in to the landscape. Take my advise, use Tom. You will not regret it."
Response time2 days
2 neighbors recently requested a quote
Recommended by100%of homeowners
Roadway Excavators Inc.
5.0(
2
)

Serving Merrimack, NH and surrounding areas

Approved

In business since 1996

Free estimates

Offers commercial services

Roadway Excavators Inc. is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests and make their concerns the basis of our business

Response time6 hrs
15 neighbors recently requested a quote
Recommended by100%of homeowners
Avatar for BMP Consultants
BMP Consultants
5.0(
6
)

Serving Merrimack, NH and surrounding areas

Call us today for all your excavating needs! We handle start-to-finish septic system installations. We will work with any design team you may already have in place. We do not provide maintenance or pumping services.

Septic Tank Project
Recommended by100%of homeowners
Avatar for Choice Home Warranty
Choice Home Warranty
4.0(
5,676
)

Serving Merrimack, NH and surrounding areas

In business since 2008

Emergency services offered

Credit card accepted

"I would highly recommend choice over any home warranty as a home owner i had a major problem with my hvac system and they got it replaced in a timely fashion much respect for them don't miss out on a great deal"
Recommended by82%of homeowners
Avatar for Primos LLC
Primos LLC
5.0(
8
)

Serving Merrimack, NH and surrounding areas

In business since 2010

Free estimates

Emergency services offered

Primos offers Commercial/Residential Concrete patios/driveways/stamped and decorative, Asphalt Paving/Sealcoating, Paver Patios and Retaining Walls. We also offer excavating and drainage, plus sewer line replacements. \nWe will offer the best price with fast, reliable, and professional service. Our customers are our number 1 priority. We listen to exactly what you looking for and we will make sure you are happy before we leave.\n

Recommended by100%of homeowners
Showing 1-10 of 26
FAQs for septic system installation and replacement projects in Merrimack, NH

The smallest standard septic system uses a 500-gallon tank, which costs between $875 and $1,150 installed. This size works well for single-occupant dwellings with minimal wastewater production. However, many local regulations specify minimum tank sizes, so check with your building department before committing to this compact option. Some jurisdictions require at least 750 gallons regardless of home size to ensure adequate waste processing capacity.

The installation timeline varies based on site conditions, permit processing, and contractor schedules. The process includes obtaining permits, conducting soil tests, excavation, tank placement, leach field construction, and final connections. Weather conditions, soil challenges, and inspection scheduling can all affect the overall timeline. It's wise to begin planning well in advance of when you need the system operational.

The most economical approach is to install a conventional anaerobic system with a plastic tank. To minimize costs while maintaining legality, obtain multiple quotes from licensed installers, consider scheduling during their slower seasons, and handle basic site preparation yourself. Never skip permits or required testing to save money—illegal installations can result in significant fines and mandatory removal, ultimately costing far more than doing it right initially.

Regular pumping helps prevent system failures and extends operational life. Most small systems require pumping every three to five years, though frequency depends on household size and usage patterns. Pumping services cost between $290 and $530, making this maintenance expense relatively minor compared to potential repair costs ranging from $500 to $2,600 for neglected systems. Establishing a regular maintenance schedule based on your installer's recommendations helps avoid costly emergency services.

The Merrimack, NH homeowners’ guide to septic system installations and replacements

From average costs to expert advice, get all the answers you need to get your job done.