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Find Septic system installers and replacers in Longmont

Avatar for Afford-A-Rooter
Afford-A-Rooter
4.7(
119
)

Serving Longmont, CO and surrounding areas

Angi Approved

In business since 2003

Free estimates

Emergency services offered

"Jason Dodge did a great job. Not only did he snake the drain in no time at all but he noticed the hot and cold water were reversed on my sink faucet and in 3 minutes he corrected it no charge! He couldn't have been nicer. I was only charged $100. for the whole thing. they have definitely become my go-to plumber!"
Additional Photos
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+7

Response time3 days
Recommended by89%of homeowners
Avatar for Crow Creek Septic Services LLC
Crow Creek Septic Services LLC
5.0(
11
)

Serving Longmont, CO and surrounding areas

Angi Approved

Super Service Award Winner

In business since 2025

Free estimates

Credit card accepted

"We had emergency septic situation where our effluent pump had failed, and our tank was FULL. Crow Creek Septic Services came out on a Sunday and pumped the tank and confirmed that the pump had indeed failed. They ordered a new pump and did all of the repairs for us. They did an excellent job at a very reasonable price. Jacob and Tim were great guys and great to work with as well. Veteran owned and operated - we highly recommend them!"
Response time11 hrs
Response rate94%
8 neighbors recently requested a quote
Dr. Drain
5.0(
9
)

Serving Longmont, CO and surrounding areas

Angi Approved

In business since 2014

Free estimates

Credit card accepted

"Jordan was awesome! He initially sent one of his guys out to check for some gurgling and sediment in our plumbing in the basement. They took a good look and found some grading issues with our pipes. Jordan followed up with me after and then committed to coming out himself to determine options. Throughout it all he was very communicative and extremely knowledgeable. We discussed some options and moved forward with the one that made the most sense. The issue was addressed and Jordan followed up later on to make sure everything was still good. Highly recommend Jordan and team dr.drain!"
Best Dog Ever
Pre Lined CIPP Pipe
Busy Day, Boulder CO
Wining
NuFlow Liner

+1

Response time2 hrs
Response rate100%
3 neighbors recently requested a quote
Avatar for All Sewer and Plumbing Services
All Sewer and Plumbing Services
4.8(
12
)

Serving Longmont, CO and surrounding areas

Angi Approved

In business since 2010

Free estimates

Warranties offered

"Eloy and his team were extremely helpful in identifying our issue and quickly repairing our collapsed sewer line. Jeff, the owner, was also extremely responsive and helpful in working with insurance and talking me through the process. The quality of communication and of the work was higher than others and the price was lower. Definitely recommending these guys to all my friends."
Response time2 hrs
Response rate89%
8 neighbors recently requested a quote
Avatar for Colorado Paradise Builders, LLC
Colorado Paradise Builders, LLC
5.0(
9
)

Serving Longmont, CO and surrounding areas

Angi Approved

In business since 1997

Free estimates

Customers say: Terrific value

"Francisco Garcia did an excellent job finishing our basement. The work quality is excellent. The communication and flexibility throughout the project was excellent. The project finished on time within budget with zero surprises. Any concerns that arose were addressed expeditiously and professionally. I highly recommend Colorado Paradise Builders for your next project. The building inspections were coordinated by Colorado Paradise Builders and passed easily. We learned while talking to the inspectors that we had a gift by using Francisco as a general contractor. They mentioned other people in the business may not provide the level of customer service and professionalism which Colorado Paradise Builders demonstrated on our basement finishing project. I could not be more enthusiastic with a recommendation."
Medina Residence
Medina Residence
Windsor custom home
Windsor custom home
Schmitz basement finish

+5

Response time1 day
Response rate86%
5 neighbors recently requested a quote
Showing 1-10 of 16
FAQs for septic system installation and replacement projects in Longmont, CO

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 Longmont, CO 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.