1500 Gallon Precast Concrete Monolithic Septic Tank Overview

1500 gallon septic tanks are designed to hold 1500 gallons of liquid. This top-seam style concrete septic tank offers the ability to run the pipe from the house to either one of its side or center inlets. The same option is available on the outlet of the tank, going out to the leach field from its side or out its middle outlet. Polylok IV closed end boots are used for the tank’s penetrations, giving a flexible, watertight connection to the pipe entering and leaving the precast structure. Meets all best-practice requirements of ASTM C 1227 & NPCA.

1500 Gallon Monolithic Septic Tank Details
Tank dimensions	10’10” x 6’4” x 5’8”
Number of bedrooms supported	5
Pre-assembled	Yes
Ideal for high water table	Yes
Average retail cost	$1375
Number of covers (lids)	2
Can come in traffic rated (H20) capacity	Yes
Concrete strength	5,000 PSI
What are its gallons per vertical inch	31
Weight	12,500 lbs.
Fiber re-enforced	Yes
Number of inlets boots (Up to schedule 40 pipe can slide through)	3
Height of Inlet from bottom of tank to bottom of pipe	56”
Number of outlets boots (Up to schedule 40 pipe can slide through)	3
Height of outlet from bottom of tank to bottom of pipe	53”
Required height of inlet baffle (20% of liquid level)	10”
Required height of outlet baffle (40% of liquid level)	20”

Frequently Asked Questions

How much does a 1500 gallon precast concrete septic tank cost?

Answer: The average retail cost for a 1500 gallon precast concrete septic tank is $1,375.00.

How many bedrooms does a 1500 gallon septic tank support?

Answer: In New Hampshire a 1500 gallon septic tank will support up to 5 bedrooms.

Is it ideal for properties with high water tables?

Yes. Ideally you want a monolithic septic tank where the seam is at the very top of the septic tank in high water table situations. The liquid is below the lid so it can’t leak in or out.

How much does a 1500 gallon concrete septic tank weigh?

Our 1500 gallon tanks weigh around 12,500 lbs., but weight varies slightly with precast manufacturers depending on the dimensions, wall thickness, floor & top thickness, & rebar reinforcement.

Can you drive over a 1500 gallon concrete septic tank?

It depends on the design rating. We manufacturer it in 3 variations: H-10 is for pedestrian traffic with 300 lbs. of live load per square foot plus 3’ of burial depth. HD is for burial depth up to 5’. H-20 is for drive over traffic & up to 6’ of burial depth.

Can you install a 1500 gallon concrete septic tank in 1 piece?

Yes, we can. Our cranes are capable of setting up to a 1750 gallon tank in 1 piece.

Features/Details*

1500 gallon septic tank is used in 5 bedroom systems.
Also used as a pump station
Common size for grease traps
Is delivered pre-assembled for ease of installation
Top seam tank for use in high water table areas or where preventing water infiltration is critical

* Details shown are NH-specific; for details of other states’ specifications.

You may also be interested in these popular precast concrete septic tanks.

About the Author:

My father started the Andrew J. Foss, Inc. precast concrete company in 1963 at the age of 19. My precast education started at a very young age. He taught me everything I know about creating quality precast concrete products, from septic tanks to concrete headwalls. He also taught me to succeed in business you need to offer an exceptional product and treat your customers as you would expect to be treated. Now, as an owner of the company along with my brother Matthew, we've taken everything we've learned from our father to start the next generation of our family-owned precast concrete company.

1500 Gallon Septic Tanks: Precast Monolithic