Pleased With Quality & Service

“We were happy with the quality of the product as well as the follow up service. The crew was efficient and did a great job.”

William A.

Superior Customer Service

“Superior Tank took care of us in our time of need and had the best price around. Mr. Huel took very good care of us from start to finish as did the crew putting the tank up. Superior Tank was also recommended to us by a neighboring water company who was very pleased with their work as well.  Thank you Superior Tank .”

Quinn A.

Excellent Product & Service

“Excellent product and very good support service.”

Elson G.

The quality of the build was excellent

“The tank you built for us in 2002, has absolutely no wear on the Powder Coating or any other feature of the tank. The quality of the build was excellent, we automatically go to Superior for our tank needs as it is a known quantity.”

Robert S.

Excellent Work

“Just wanted to let you know that your work crew was excellent. Thanks for your professionalism.”

Jack C.

Delivery & Installation

“I have purchased tanks from other companies, but none are delivered and installed with less problems than Superior Tank.”

Donald S.

Satisfied Customer

“Very good and timely response.”

Steve M.

Customer For Over 30 Years

“We have done business with Superior Tank for over 30 years and plan on doing more business.”

Johnny G.


“Please let your crew know that I appreciate their work and efforts to get this tank done. GOOD JOB!!”

Michael B.

Have Always Used Superior

Have always used Superior and don’t know any water supply company that doesn’t use Superior.

Mark C.

Fantastic Bolted Steel Tank!

“Absolutely fantastic tank!  Your crew was a very impressive team; the tank went up much quicker than we had expected.”

Ed C.

I only deal with Superior

“I DO NOT deal with any other bolted tank company, period. I deal only with Superior because of Huel, and he makes sure I get the best product that Superior has to offer and Huel stands behind what he puts his name on.”

John G.

A Historic Moment

“Today  water began flowing to our customers. A bit of clean-up, replace the Brown’s gate, and we will be finished. One bit of history I remember tells me that this is the first project of this magnitude since the Empire State Building to finish ahead of schedule and (slightly) below budget. Thank you for your support.”

Peter S.

Superior was one of my better decisions

I can tell you that I was extremely happy with the professionalism of the entire process from design to install. Superior was one of my better decisions while running Saltwater Disposal of North Dakota

David K.



Standards & Specifications

Standards & Specs

Commitment to Quality

At Superior Tank Co., Inc., quality is at the forefront of everything we do. Our bolted steel tanks and welded steel tanks adhere to a variety of recognized industry standards ensuring your new steel storage tank will meet stringent levels of quality. Superior Tank Co., Inc. (STCI) and our bolted tank manufacturing processes are API SPEC Q1/ISO 9001:2008 certified resulting in consistent product quality, customer satisfaction and on-time delivery. Our state of the art manufacturing facility and precision machinery reliably fabricates bolted tanks with extreme accuracy. Over the last 30+ years of manufacturing welded and bolted steel storage tanks, we have refined our design and production progresses resulting in bolted tanks tough enough to stand the test of time.
In addition to meeting ISO 9001:2008 requirements, our steel tanks meet the standards of the American Water Works Association (AWWA), National Fire Protection Association (NFPA), American Petroleum Institute (API), NSF and FM Approvals. We engineer each steel storage tank to the specific application and local building codes ensuring our ground storage tanks will withstand site conditions and function at optimum levels.

API SPEC Q1 / ISO 9001:2008

STCI has earned API SPEC Q1/ISO 9001:2008 Quality Managements System (QMS) Certification. This recognized certification ensures numerous processes and procedures are followed, ensuring a defect free product meeting customer expectations and is delivered to customers on time.

An external API audit team reviews numerous aspects of our steel tank manufacturing process from sales ordering through bolted steel tank production and storage tank installation, to ensure adherence to the established QMS. The end result is a high quality steel tank designed and manufactured to exact customer requirements, then delivered within the scheduled time frame.

American Petroleum Institute (API) Q1 certification

In addition to ISO 9001:2001 Certification our manufacturing processes and our steel storage tanks comply with American Petroleum Institute (API) Q1 Spec. The API Q1 Spec complements the ISO 9001:2001 Certification as it focuses on meeting the API12B Standard and the accurate and responsible manufacturing of products to be used on the petroleum industry with use of risk assessment and risk management procedures.

Several of the additional areas of focus for the API Q1 Spec include formal personnel training, contingency planning, supply chain control, preventative maintenance of equipment and tools, product design validation and managing changes in a controlled manner. These items are extremely relevant to the oil industry where safety is paramount.

AWWA D103-09

American Water Works Association (AWWA) standards are intended to represent a consensus of the water supply industry that the product described will provide satisfactory service. Based on the accumulated knowledge and experience of manufacturers, engineers and end-users of bolted steel tanks, AWWA Dl03-09 is the standard that governs factory powder coated bolted steel tanks for water storage, set by the American Water Works Association (AWWA). This standard is ANSI (American National Standards Institute) approved.

AWWA D100-11

AWWA standards are intended to represent consensus of the water supply industry that the product described will provide satisfactory service. Based on the accumulated knowledge and experience of manufacturers, engineers and end-users of welded steel tanks, AWWA D100-11 is the standard that governs welded carbon steel tanks for water storage, set by the American Water Works Association (AWWA). This standard is ANSI approved.

NSF/ANSI 61 & 372

In addition to compliance with AWWA D103 standards, our bolted steel water storage tanks over 14,309 gallons have earned the NSF International Certification when properly equipped. The NSF/ANSI 61 / 372 certification of gives our customers the assurance that our bolted tanks meet the highest requirements for storage of drinking water. To become certified, our bolted steel tanks were rigorously tested and evaluated to verify they met stringent performance and durability requirements. In addition, our bolted tanks were tested for lead content and found to conform to the requirements for “lead free” product listing. To be NSF Certified, our bolted tanks must include our NSF Certified epoxy Tank Tan powder coating, encapsulated tank hardware and EPDM gasket material.

Click here for our NSF Listings


Set by the American Petroleum Institute (API), the API SPEC 12B specification covers the material, design, and erection requirements for bolted steel tanks used for storage of oil and other petrochemicals. It covers bolted steel ground storage tanks in nominal capacities of 100 to 10,000 barrels for production service, including appurtenance requirements. When a tank meets or exceeds all of the strict standards of API SPEC 12B and the manufacturer has earned API SPEC Q1/ISO 9001:2008 certification for quality, the bolted steel tank can proudly display the API Spec 12B Monogram. Superior Tank Co., Inc. is one of the few companies in the world which can include the API Spec 12B Monogram on its bolted steel tanks for oil storage.


Similar to API 12B, the API 12D specification is set by the American Petroleum Institute (API) and covers the material, design and erection requirements for welded steel oil storage tanks. It covers welded steel ground tanks with nominal capacities of 500 to 10,000 barrels for production service, including appurtenance requirements. These welded tanks are vertical cylindrical steel tanks that are installed above ground and store liquids at atmospheric pressure.

API 650

This standard is designed to provide the petroleum industry with steel tanks of adequate safety and reasonable economy for use in the storage of crude oil and other petroleum products. It is intended to help purchasers and manufacturers in ordering, fabricating, and erecting bolted and welded tanks used for storage of oil and other petrochemicals. API Standard 650 covers material, design, fabrication, erection, and testing requirements for vertical, cylindrical, above ground, closed- and open-top, welded steel storage tanks in various sizes and capacities. This standard applies only to steel tanks whose entire bottom is uniformly supported and to non-refrigerated storage tanks.

API 653

This standard covers steel ground storage tanks built to API 650. It provides minimum requirements for maintaining the integrity of such bolted or welded tanks after they have been placed in service and addresses inspections, repair, alteration, relocation and reconstruction. The standard covers the tank foundation, bottom, shell, structure, roof, attached appurtenances, and nozzles to the face of the first flange, first threaded joint, or first welding-end connection and governs welded crude oil storage tanks that have been placed in service.


The NFPA 22 standard for water storage tanks for fire protection provides the industry’s most up-to-date requirements for the design, construction, installation and maintenance of storage tanks and accessory equipment that supply water for fire protection. The standard includes tank foundations, towers, valve enclosures, pipe connections and fittings.

FM Approvals

The FM Approvals standard ensures our steel water storage tanks meet stringent design criteria for water storage for fire protection. Ensuring the water tank functions properly is key to saving lives and property in the event of a fire or other disaster. The FM Approval designation provides our customers the confidence that our steel tanks will work as designed and provide the required water for fire protection.