Top-rated septic system installers and replacers.

Get matched with top septic system installers and replacers in Merrimack, NH

Enter your zip and get matched with up to 3 pros

Matching on HomeAdvisor

Share some details icon
Share some details about your home project.
Match with local pros icon
Within moments, match with highly-rated local pros.
Compare quotes icon
Compare quotes and choose the best pro for the job.

Find Septic system installers and replacers in Merrimack

Corriveau Construction Company

5.00(
5
)
Approved Pro

Corriveau Construction Company

5.00(
5
)
Approved Pro
Customers say: Quick response
27 local quotes requested
53 years of experience

Bob has been in business for 50 years. Started working on his own property and was disappointed in the quality of other people's work so he decided to go leave a career in electronics sales and into business himself.Became a career in building and developing.Built subdivisions.Built roads and all site work for new homes.

"This is the best construction pro I had in my life. If there is anyone's looking for the best construction crew this company is the best. I've never had anyone in my life as good as Corriveau construction company. They went beyond and above what I expected. "

Bill A on September 2025

Bob has been in business for 50 years. Started working on his own property and was disappointed in the quality of other people's work so he decided to go leave a career in electronics sales and into business himself.Became a career in building and developing.Built subdivisions.Built roads and all site work for new homes.

"This is the best construction pro I had in my life. If there is anyone's looking for the best construction crew this company is the best. I've never had anyone in my life as good as Corriveau construction company. They went beyond and above what I expected. "

Bill A on September 2025


Innovative Septic Solutions

4.59(
27
)
Approved Pro

Innovative Septic Solutions

4.59(
27
)
Approved Pro
Customers say: Quality work
16 local quotes requested
40 years of experience

Serving all of Hillsborough and the surrounding counties, the professionals at Innovative Septic Solutions are the go-to, full service septic designers and installers you can trust to get the job done right! Call now for a consultation!

"I was selling a 71 year old home and the inspection revealed a failing septic system. I had called another company as well as Bob snd had opted to use the other company which was local in Merrimack. Sadly I was told it would be 6 to 8 weeks. I could not wait that long since the house needed to be sold before winter. I called Bob and he began the same day! He explained he was also an engineer and could do the required septic design himself. He was able to have the entire job done in 2 weeks and we had a contract to sell before he finished. He was a delight to work with and I woukd recommend this company without any hesitation."

Betty F on October 2025

Serving all of Hillsborough and the surrounding counties, the professionals at Innovative Septic Solutions are the go-to, full service septic designers and installers you can trust to get the job done right! Call now for a consultation!

"I was selling a 71 year old home and the inspection revealed a failing septic system. I had called another company as well as Bob snd had opted to use the other company which was local in Merrimack. Sadly I was told it would be 6 to 8 weeks. I could not wait that long since the house needed to be sold before winter. I called Bob and he began the same day! He explained he was also an engineer and could do the required septic design himself. He was able to have the entire job done in 2 weeks and we had a contract to sell before he finished. He was a delight to work with and I woukd recommend this company without any hesitation."

Betty F on October 2025



Avatar for Terraform Site Contracting, Corp.

Terraform Site Contracting, Corp.

5.00(
5
)
Approved Pro

Terraform Site Contracting, Corp.

5.00(
5
)
Approved Pro
Customers say: Quick response
20 years of experience
Free onsite estimate

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!

"Tim was excellent to work with. He was quick to respond and quote. Tim handled all the details, coordinating with the Plumbers, Designers, and Permits. While installing the Septic system, he was also hired to do some grading of the property and install a foundation for a large addition. His quotes were fair, he stayed on budget, and his subcontractors were excellent. Most importantly he answered all of my concerns and questions throughout the job. I will definitely recommend his company. "

Thomas G on October 2025

We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!

"Tim was excellent to work with. He was quick to respond and quote. Tim handled all the details, coordinating with the Plumbers, Designers, and Permits. While installing the Septic system, he was also hired to do some grading of the property and install a foundation for a large addition. His quotes were fair, he stayed on budget, and his subcontractors were excellent. Most importantly he answered all of my concerns and questions throughout the job. I will definitely recommend his company. "

Thomas G on October 2025


Tom Howe Septic Systems and Excavation

5.00(
6
)
Approved Pro

Tom Howe Septic Systems and Excavation

5.00(
6
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
57 years of experience

A few services we provide are residential and commercial septic pumping, and drain field install/repair. We are conveniently located to serve Hillsborough County. We are licensed, bonded and insured. Tom Howe Septic Systems is a family-owned and operated business that has served the Merrimack area since 1968.

"A"

Tariq S on May 2022

A few services we provide are residential and commercial septic pumping, and drain field install/repair. We are conveniently located to serve Hillsborough County. We are licensed, bonded and insured. Tom Howe Septic Systems is a family-owned and operated business that has served the Merrimack area since 1968.

"A"

Tariq S on May 2022


H. K. White & Son, LLC

5.00(
1
)
Approved Pro

H. K. White & Son, LLC

5.00(
1
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
65 years of experience

Welcome to H.K. White & Son, LLC! We are committed to exceeding your expectations. As experts, we will handle your needs with the high quality expertise that your home or business deserves. We offer competitive prices and customer satisfaction is our number one priority. Call us now!

"They were very approachable, and made me feel comfortable as a woman dealing with contractors. Very professional, and on time, even checking in when their day was done. I would say they went above and beyond."

Kathy Y on March 2019

Welcome to H.K. White & Son, LLC! We are committed to exceeding your expectations. As experts, we will handle your needs with the high quality expertise that your home or business deserves. We offer competitive prices and customer satisfaction is our number one priority. Call us now!

"They were very approachable, and made me feel comfortable as a woman dealing with contractors. Very professional, and on time, even checking in when their day was done. I would say they went above and beyond."

Kathy Y on March 2019


Granite State Sewer & Drain Cleaning Co

4.92(
12
)
Approved Pro

Granite State Sewer & Drain Cleaning Co

4.92(
12
)
Approved Pro
Customers say: Quality work
Recommended by 91% of Angi customers
Recommended by 91% of HomeAdvisor customers
17 local quotes requested

Granite State Sewer & Drain Cleaning Co is your go-to plumbing and drain cleaning expert in New Hampshire. With our extensive experience and top-notch service, we stand out from the competition. Contact us today for all your plumbing needs! Additional DBAs - Granite State Sewer Pumps, Granite State Sewer & Drain Cleaning Inc.

"good job and reasonable pricing"

David S on September 2025

Granite State Sewer & Drain Cleaning Co is your go-to plumbing and drain cleaning expert in New Hampshire. With our extensive experience and top-notch service, we stand out from the competition. Contact us today for all your plumbing needs! Additional DBAs - Granite State Sewer Pumps, Granite State Sewer & Drain Cleaning Inc.

"good job and reasonable pricing"

David S on September 2025


Miller Environmental

No reviews yet

Miller Environmental

No reviews yet
28 years of experience

Family owned and operated

Family owned and operated


Carlton Plumbing & Heating

No reviews yet

Carlton Plumbing & Heating

No reviews yet
24 years of experience

Here at Carlton Plumbing & Heating, we are a 24 hour service! Call to make your appointment today!

Here at Carlton Plumbing & Heating, we are a 24 hour service! Call to make your appointment today!


Avatar for American Excavating Corporation

American Excavating Corporation

No reviews yet

American Excavating Corporation

No reviews yet
35 years of experience

- Site Work - Material Sales - Trucking - - Excavation - - Driveway Repairs - - Driveway Paving - - Yard Expansions - - New Septic Systems - - Rock Removal - - Stump Removal - - Drainage - - Any and All excavation needs! * Material Sales * & Delivery Stone Sand Loam Fill And many more... American Excavating Corporation is a family owned business in Derry NH. American Excavating has been in business for 30 years serving local businesses, municipalities, developers and homeowners alike. We are a NHDOT certified contractor that can bring experience and professionalism to your home or business project. We have the equipment and personnel to get your job done on time and on budget. American Excavating looks forward to helping you with your next project. We always offer free quotes and knowledge to anyone who asks. If we cant do your project, we can align you with someone who can.

- Site Work - Material Sales - Trucking - - Excavation - - Driveway Repairs - - Driveway Paving - - Yard Expansions - - New Septic Systems - - Rock Removal - - Stump Removal - - Drainage - - Any and All excavation needs! * Material Sales * & Delivery Stone Sand Loam Fill And many more... American Excavating Corporation is a family owned business in Derry NH. American Excavating has been in business for 30 years serving local businesses, municipalities, developers and homeowners alike. We are a NHDOT certified contractor that can bring experience and professionalism to your home or business project. We have the equipment and personnel to get your job done on time and on budget. American Excavating looks forward to helping you with your next project. We always offer free quotes and knowledge to anyone who asks. If we cant do your project, we can align you with someone who can.

...
Showing 1-10 of 443
FAQs for septic system installation and replacement projects in Merrimack, NH

Most septic system replacements require several days to complete, not including permitting and preparation time. The process begins with site assessment and testing, followed by excavation, component installation, and final inspection. Weather conditions, property accessibility, and inspection schedules can all affect your project timeline. Your contractor can provide a more specific estimate based on your property's unique characteristics.

Standard homeowners' insurance policies don't cover septic system replacement due to age or normal deterioration. Coverage may apply if damage results from specific covered events, but routine maintenance and eventual replacement are generally considered homeowner responsibilities. Review your policy details or speak with your insurance agent to understand your specific coverage limitations.

Look for multiple indicators such as slow-draining fixtures, unusual gurgling sounds in plumbing, sewage odors inside or outside your home, or wet spots in your yard. Unusually lush grass over the drain field area, frequent backups, or recurring repair needs might signal system failure. Addressing these warning signs promptly can prevent property damage and health hazards.

DIY septic installation is not recommended and may violate local regulations. Professional installation ensures compliance with health codes, proper design for your specific site conditions, and appropriate safety measures. The specialized equipment, technical knowledge, and permitting requirements make this a job best left to licensed professionals who can guarantee the system's safety and effectiveness.

With proper maintenance, including regular pumping, a drain field lasts 20 years. Various factors influence system longevity, including household size, water usage patterns, and soil conditions. Regular professional inspections can help determine when replacement becomes necessary. If your system requires increasingly frequent repairs, replacement might be more economical than continuing to address individual problems.

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.