Frequently Asked Questions

Our tanks are sold through Norwesco distributors. To locate a distributor in your area, click on “Find a Distributor” on the menu at the top of the screen or click on the green “Find a Distributor” tab on the right side of the screen.

You must purchase tanks in full truckload quantities. Contact Norwesco Customer Service and we can put you in contact with a manufacturer’s rep who can give you all of the details.

The tanks shown in the Water & Waste section of our website carry a three year warranty from date of manufacture. Should a defect appear within the warranty period, Norwesco will supply a new, equivalent tank in replacement thereof. Norwesco’s liability is limited to the value of the tank itself and specifically excludes the cost of installation and/or removal or consequential damages.

Most Norwesco tanks are embossed with a serial number that is 1/2″ in height. On a below ground tank you will find the serial number at the “outlet” end of the tank near the edge of the manway. On an above ground tank, you will usually find the serial number near the fill-opening of the tank with the exception of large vertical tanks.  Vertical tanks 5000 gallons and larger have the serial number embossed 48″-52″ up from the bottom of the tank on the sidewall in line with the gallonage markers. . To get a general idea of when your tank was manufactured, click on the following link, Understanding Norwesco serial numbers.  If you need a specific manufacture date, please contact your Norwesco distributor.

Norwesco uses a linear, high-density polyethylene resin that provides outstanding environmental stress crack resistance. The resin is UV stabilized but by keeping an above ground tank sheltered or indoors you will prolong the life of your tank. Click on the following link for specific information regarding the resin used to manufacture Norwesco above ground water tanks and below ground cistern tanks. Resin Information

Yes, it is safe to store water in the Norwesco above ground tanks and below ground cistern tanks shown on our website. The resin used to manufacture these tanks meets FDA specifications for safe storage of potable water. Click on the following link for specific information regarding the FDA status of the resin. FDA status of resin

NSF International, founded in 1944 as the National Sanitation Foundation, is known for the development of standards, product testing and certification services in the areas of public health, safety and protection of the environment.  Norwesco was the first polyethylene tank producer to receive the NSF61 certification, where applicable, for our potable water tanks.

The NSF61 certification process is done on a plant-by-plant basis. We currently have tanks that are NSF61 certified in five of our manufacturing facilities: Fairfield TX, Hanford CA, Tooele UT, Washougal WA & Lancaster OH. Click on the following link for information regarding the NSF61 status certification for the five facilities listed above.  NSF certification

Generally, colors are used to designate one grade or type of tank from another and is for product identification only except for the Black or Dark Green Water tanks. Our standard color for septic tanks is yellow or green; bruiser tanks are light blue and below ground cisterns and above ground water tanks are natural or white. We also offer Black or Dark Green Water Only tanks.

Polyethylene storage tanks have a maximum storage temperature of 120 degrees F. Contents with a temperature in excess of 120 degrees F – even for a short period of time – can weaken the tank’s structural integrity and make it susceptible to deformation and failure.

No, Norwesco products are exempt from the MSDS requirements established in the Hazard Communication section (29 CFR 1910.1200) of the Occupational Safety and Health Administration (OSHA) regulations.  Norwesco products are classified as “articles” as referred to in 1910.1200(b)(6)(v) and as defined in 1910.1200(c).

1910.1200(c) “Definitions”

“Article” means a manufactured item other than a fluid or particle: (i) which is formed to a specific shape or design during manufacture; (ii) which has end use function(s) dependent in whole or in part upon its shape or design during end use; and (iii) which under normal conditions of use does not release more than very small quantities, e.g., minute or trace amounts of a hazardous chemical (as determined under paragraph (d) of this section), and does not pose a physical hazard or health risk to employees.

Tanks specifically designed for above ground use cannot be put underground. If it is put below ground, the weight of the earth around the tank will cause the walls to collapse.

The tank itself does not have a minimum temperature rating. If you plan to keep the liquid in the tank and you know that it will freeze, make sure that you leave room for expansion. The most likely place to crack on the tank is the bulkhead fitting which can be easily replaced.

Norwesco offers two grades of above ground polyethylene tanks – premium and water. The Norwesco premium tank is designed and manufactured to hold a product with a specific gravity up to 1.5, (12.5 pounds per gallon) at 73 degrees F. The Norwesco water tank is designed and manufactured to hold product with a specific gravity up to 1.1, (9.2 pounds per gallon) at 73 degrees F.  (An increase in liquid temperature will substantially decrease the specific gravity rating!)