Top-rated septic system installers and replacers.

Get matched with top septic system installers and replacers in Watertown, MA

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 Watertown

Avatar for D J Morris Contracting Co Inc

D J Morris Contracting Co Inc

4.91(
23
)
Approved Pro

D J Morris Contracting Co Inc

4.91(
23
)
Approved Pro
Customers say: True professional
Recommended by 95% of Angi customers
Recommended by 95% of HomeAdvisor customers
14 local quotes requested

Owner operated, Serving local residents for over 30 years, with our 8 employees, we work with engineers and town boards of Health to install qualified Title 5 Septic Systems. We are able to take you effortlessly through the whole process, from test holes to reseeding. We offer free estimates and competitive pricing. Additional website - www.trustthisbiz.com/djmorris_contracting. Additional DBA - DJ Morris Conracting Company.

Owner operated, Serving local residents for over 30 years, with our 8 employees, we work with engineers and town boards of Health to install qualified Title 5 Septic Systems. We are able to take you effortlessly through the whole process, from test holes to reseeding. We offer free estimates and competitive pricing. Additional website - www.trustthisbiz.com/djmorris_contracting. Additional DBA - DJ Morris Conracting Company.


"David did a great job with our septic replacement and installation. He came in with the best quote. He was easy to communicate with and everything went smoothly. He did a wonderful job with the landscaping after the installation was completed. The grass grew back quickly. We wish we had done this sooner. Would definitely recommend his services. "

Rick L on October 2025

Experienced excavation company specializing in all residential and commercial needs. Septic systems designed, installed and all other excavation needs.

"David did a great job with our septic replacement and installation. He came in with the best quote. He was easy to communicate with and everything went smoothly. He did a wonderful job with the landscaping after the installation was completed. The grass grew back quickly. We wish we had done this sooner. Would definitely recommend his services. "

Rick L on October 2025


Avatar for Holliston Sewer Service Inc

Holliston Sewer Service Inc

4.89(
57
)
Approved Pro

Holliston Sewer Service Inc

4.89(
57
)
Approved Pro
Customers say: True professional
Recommended by 96% of Angi customers
Recommended by 96% of HomeAdvisor customers
10 local quotes requested

• 2016 Super Service Award Winner - 3rd Consecutive Year! • Since 1954, Holliston Sewer Service Inc has remained a Locally Owned & Family Operated Sewer Service Company Inc providing Septic Services you can count on, including Septic Tank Pumping, Title 5 Inspections, & Septic Tank Repairs for 3 Generations! • We serve Residential, Commercial, & Industrial Clients • Your Best Choice for Septic Pumping Services • From Septic Tank Pumping to Leach Line Jetting, We are your best choice for a variety of Septic & Sewer Services • Let us provide you with quality service in the most cost effective manner • Call (508) 429-6262 to Schedule an Estimate or Appointment Today!

"Great and kind."

Nicolas D on January 2024

• 2016 Super Service Award Winner - 3rd Consecutive Year! • Since 1954, Holliston Sewer Service Inc has remained a Locally Owned & Family Operated Sewer Service Company Inc providing Septic Services you can count on, including Septic Tank Pumping, Title 5 Inspections, & Septic Tank Repairs for 3 Generations! • We serve Residential, Commercial, & Industrial Clients • Your Best Choice for Septic Pumping Services • From Septic Tank Pumping to Leach Line Jetting, We are your best choice for a variety of Septic & Sewer Services • Let us provide you with quality service in the most cost effective manner • Call (508) 429-6262 to Schedule an Estimate or Appointment Today!

"Great and kind."

Nicolas D on January 2024


Avatar for Schofield Environmental

Schofield Environmental

4.17(
9
)
Approved Pro

Schofield Environmental

4.17(
9
)
Approved Pro
Customers say: Quick response
26 years of experience
Free onsite estimate

At Alpha Environmental, we are very well versed in all available septic solutions for your project. We design and install the best septic systems to the highest standards. Whether we are repairing your current septic system or installing a new one, one thing is certain; nobody brings a higher level of professionalism into your home. We value quality and guarantee a pleasurable customer service experience. We look forward to serving you. Give us a call for a free estimate today!

"Dave is design/build - heck of a lot better than hiring multiple contractors! "

Harold M on April 2025

At Alpha Environmental, we are very well versed in all available septic solutions for your project. We design and install the best septic systems to the highest standards. Whether we are repairing your current septic system or installing a new one, one thing is certain; nobody brings a higher level of professionalism into your home. We value quality and guarantee a pleasurable customer service experience. We look forward to serving you. Give us a call for a free estimate today!

"Dave is design/build - heck of a lot better than hiring multiple contractors! "

Harold M on April 2025


Avatar for R Cox Enterprises

R Cox Enterprises

5.00(
5
)
Approved Pro

R Cox Enterprises

5.00(
5
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
10 local quotes requested

At, R Cox Enterprises Inc., our company is based on the belief that the needs of our customers are of the utmost importance. Our team is committed to meeting those needs. We welcome the opportunity to earn your trust and deliver you the best service. No job is too big or too small for our experienced team. Call today for a quote.

"Honest, reasonable and professional. Ron is a great guy."

George R on March 2024

At, R Cox Enterprises Inc., our company is based on the belief that the needs of our customers are of the utmost importance. Our team is committed to meeting those needs. We welcome the opportunity to earn your trust and deliver you the best service. No job is too big or too small for our experienced team. Call today for a quote.

"Honest, reasonable and professional. Ron is a great guy."

George R on March 2024


Kennelly Construction, Corp.

5.00(
4
)
Approved Pro

Kennelly Construction, Corp.

5.00(
4
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
10 local quotes requested

Here at Kennelly Construction, Corp., we pride ourselves on providing quality service that customers can believe in. Whether it's excavation, to septic systems, we can take care of all your home's needs. With over 50 years of experience, we offer both residential and commercial services. Give us a call for a free estimate, we look forward to working with you!

"They got the job done.."

Diane L on February 2021

Here at Kennelly Construction, Corp., we pride ourselves on providing quality service that customers can believe in. Whether it's excavation, to septic systems, we can take care of all your home's needs. With over 50 years of experience, we offer both residential and commercial services. Give us a call for a free estimate, we look forward to working with you!

"They got the job done.."

Diane L on February 2021


Avatar for LMH CONSTRUCTION GROUP LLC

LMH CONSTRUCTION GROUP LLC

4.82(
11
)
Approved Pro

LMH CONSTRUCTION GROUP LLC

4.82(
11
)
Approved Pro
Customers say: Quality work
14 years of experience
Free onsite estimate

We take great pride in our experience, expertise, quality and customer service that we provide to meet every consumer's needs. It is our mission to provide excellent customer service from start to completion of a project. To understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a personal and professional manner. Our reputation is based on service, safety and quality, regardless of how large or small the job.

"Let me start off by saying that these guys are great. They did my bathroom, kept everything clean, and anytime I had question or concern, they were quick to respond. I now will rehire them to do my basement and remodel my kitchen?"

Barbara S on October 2025

We take great pride in our experience, expertise, quality and customer service that we provide to meet every consumer's needs. It is our mission to provide excellent customer service from start to completion of a project. To understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a personal and professional manner. Our reputation is based on service, safety and quality, regardless of how large or small the job.

"Let me start off by saying that these guys are great. They did my bathroom, kept everything clean, and anytime I had question or concern, they were quick to respond. I now will rehire them to do my basement and remodel my kitchen?"

Barbara S on October 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!


Washington Street Plumbing and Heating

No reviews yet

Washington Street Plumbing and Heating

No reviews yet
Emergency services offered

Call us today! Available 24/7/365. Ready willing and able to help with whatever problem that might arise day or night. Call us today to schedule an appointment. Why Choose Us? We are: Insured, Certified, Licensed, 24/7 emergency service, Same-day service offered, 100% guaranteed work, Professional technicians, Environmentally conscious, Factory trained and authorized.

Call us today! Available 24/7/365. Ready willing and able to help with whatever problem that might arise day or night. Call us today to schedule an appointment. Why Choose Us? We are: Insured, Certified, Licensed, 24/7 emergency service, Same-day service offered, 100% guaranteed work, Professional technicians, Environmentally conscious, Factory trained and authorized.

...
Showing 1-10 of 515
FAQs for septic system installation and replacement projects in Watertown, MA

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 Watertown, MA 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.