Holding Tanks for Sewage & Water
- Rectangle Sewage & Water Tanks
- Odd Shape Sewage & Water Tanks
- Order Your Tank
- Sewage & Water Holding Tank Q&A

The Sub Categories above are the paths to our Rectangle Tank List and our Odd Shape Tank PDF for Sewage Tanks (black water), Water storage tanks (potable water), & Gray Water Tanks (showers, tanks etc.).
If you need help finding a tank that will work for you please call, fax or email us with your dimensions. We have over 1,000 molds to choose from. It is important that you give us your max dimensions so we can narrow the search to your needs.
Not all sewage tanks and water tanks are created alike. Our manufacturer provides over 1,000 tanks that are created from prefabricated molds and can lay in any configuration you need them. This ensures your ability to customize your fitting size and placement. They are polyethylene, roto-molded (rotational molded) tanks. This means they do not have seams that are known to weaken, crack and leak due to pressure and age. With the Roto-molding process the tanks are a sturdy 3/8" thick and can withstand a lifetime of permeation free use.
Lets get started.
What we need from you:
-The dimensions of the tank you require. (Remember to leave yourself room for fittings -approx 3-5 inches)
-The tanks are of a seamless construction and can be installed in any direction.
-After we find a tank with as close to, if not the exact dimensions you require, we would then require a TANK DRAWING of the tank indicating, with dimensions, the layout of the tank that best suits your needs, the fitting placements and their sizes.
Standard tank prices include: (3) 1/2" - 2" NFPT Spin-Weld fittings (friction welded, national female pipe thread). Typically all you need is an inlet, a discharge and a vent fitting.
Fittings that are not included in the standard tank price:
- Additional FPT Spin Welds @ $5 each
- 3" Cleanout with Cap - $15.00
- Diptube discharge kit - $48.00 -A custom length Diptube is created by adhering a PVC pipe to a MPT x Slip fitting that threads into a 1-1/2" FNPT spin-weld fitting on the tank. The pipe is measured to sit approx 1/2" from the bottom of the tank, making it a very efficient way of evacuating your tank. Both a straight and a 90 degree hose adapter option is included with this kit (not glued). *Use PVC Primer and Cement to finish*
Freight is not factored into the standard tank price! Shipping options will be provided upon checkout.
Holding Tanks Are Exempt From Any Free Shipping Promotions.
NO DISCHARGE ZONE NOTICE - WASHINGTON STATE
November 2016: The EPA has reviewed Washington State's petition and has determined that a no discharge zone (NDZ) can be established for Puget Sound. The EPA found that there are adequate facilities in Puget Sound for vessels to pump out their sewage with this initial determination and are accepting public comments. EPA will prepare a final determination after the public comment period of 30 days.
What does this mean to recreational boats? There are about 2,000 to 4,000 recreational vessels in the Puget Sound area that have a federally-approved treatment system called a Type I or Type II Marine Sanitation Device (MSD) These systems will have to be isolated or the MSD be removed and add a holding tank. Any vessel that has a marine toilet must have a holding tank under the NDZ.
Here is the Proposed No Discharge Zone