Norwesco 525 Gallon Plastic Underground Water Storage Cistern Tank

Where it goes

A 525 gallon cistern is the size for a rainwater supply off a shed or a small roof, a buffer tank on a slow well so the pump has volume to draw from, a water store for a cabin or a remote site, or a small fire reserve next to a pump. Buried, it stays out of the sun and the light, which keeps the water cool and slows algae, and below the frost line it keeps working through winter. At 64 inches across the hole is modest, and the empty tank is light enough for two people to set by hand. The ground does the work after that: bed it on compacted granular fill, backfill in lifts while you fill the tank with water in step, so the wall is supported on both sides as the load goes on, and keep vehicles off the area unless the installation is designed for traffic. Norwesco's installation instructions for this tank are the authority on bedding, backfill and burial depth, and your installer follows them, not this page. If the tank is part of a rural fire supply, our guide to reservoir sizing and freeze protection for rural and remote sites covers how a tank like this fits in the stack.

Openings, fittings and risers

1. Manway. 20 inches on top: wide enough to lower a submersible pump and a float, and to get in and inspect. It is the only opening the tank comes with.
2. Inlet and outlet. None fitted. You add bulkhead fittings sized to your pipe where the inlet and the outlet suit the site. Dry-fit each one, turn it to point where the pipe runs, then tighten by hand plus a quarter turn, because once the tank is buried nothing moves again.
3. Riser. Norwesco offers one riser or extension per manhole for this tank, and this tank has one: a 6 inch extension (N-63832), a 15 inch extension (N-63833), a 24 inch extension (N-63834), a 23 inch riser with a 12 inch lid (N-63831) or a 36 inch riser with a 6 inch lid (N-63830). Add up the burial depth over the top of the tank and tell us the number; we put the right riser on the order.
4. Drawing. Norwesco's drawing for this tank, linked under Technical Drawing on this page, shows the manway position and the flat areas of wall that will take a fitting.

Sizes nearby

One size down: the 225 gallon underground cistern. The next step up is the 550 gallon underground cistern. Use the tank sizing calculator and tank sizing guide to work out the volume from your roof area or your draw, and call us if the hole is already dug and you need the shape to fit it.

Shipping and receiving

The tank ships LTL freight, 64 by 64 by 64 inches on a pallet and 170 lb, from Norwesco's Griffin, Georgia plant. The listed price is before freight; the freight cost estimator gives the lane cost to your ZIP, or send a quote request for a job that needs paperwork. Two people can take it off the truck. At the tailgate, check the part number against 44829 on the bill of lading, look at the shell and the manway rim for transit damage, and before it goes in the hole, fill it with water once above ground so any problem shows while you can still reach it; our write-up on hydrostatic acceptance testing and fill discipline covers how long to hold it.

Questions before you order? Call 866-418-1777.