Bolted Steel Tanks for Potable Water and Fire Protection Storage
Water storage is the single largest application for bolted steel tanks worldwide. Municipal utilities, rural water districts, military installations, and private water systems rely on factory-coated bolted tanks because the coating quality is unmatched by any field-applied alternative — and in potable water service, coating integrity is what keeps the water safe and the tank in compliance.
MMI Tank engineers, fabricates, and field-erects bolted steel water storage tanks from 10,000 to 5,000,000+ gallons across the western United States. Every panel is factory-coated with NSF/ANSI 61 certified linings in our climate-controlled Phoenix facility, so corrosion protection is complete before the first bolt is turned on your site.
Water Storage Applications
Potable Water Ground Storage
Treated drinking water reservoirs for municipal distribution systems, community water systems, and private supplies. Designed to AWWA D103 with NSF/ANSI 61 interior coatings. Standard aluminum dome or flat panel roofs with screened vents to prevent contamination.
Fire Protection Water Storage
Dedicated fire water tanks built to NFPA 22 requirements. Sized to your fire flow rate and duration with proper suction connections, overflow, and venting. Freeze protection systems (circulation, heating, insulation) for cold-climate installations. Bolted construction installs fast — critical when fire protection compliance is on a deadline.
Elevated Water Storage
Bolted steel tanks on composite or steel pedestals for water systems requiring elevated head pressure without pumping. Factory coating extends the full height of the structure — pedestal columns, bowl, and riser all coated before erection.
Raw Water and Well Storage
Pre-treatment holding tanks for groundwater, surface water, or blended sources. Coatings selected for your specific water chemistry to prevent iron pickup, taste/odor issues, or biological growth.
Irrigation and Agricultural Water
Large-volume seasonal storage for irrigation districts, farms, and ranches. Bolted construction is ideal for remote agricultural sites — panels ship flat and assemble without specialized welding crews. Learn more about our agriculture tanks →
Why Bolted for Water Storage?
| Factor | Bolted (AWWA D103) | Welded (AWWA D100) |
|---|---|---|
| Interior coating quality | ✅ Factory-baked, every surface | Field-applied after erection |
| NSF 61 certification | ✅ Factory-certified system | ✅ Field-certified system |
| Installation speed | ✅ 2–4 weeks | 6–12 weeks |
| Remote/rural sites | ✅ No welding logistics | Needs welders + NDE |
| Future expansion | ✅ Add rings | Not practical |
| Relocation | ✅ Disassembles | Permanent |
| Very large diameter (150+ ft) | Available | ✅ More common |
Coating Systems for Water Service
For potable water, the interior coating must meet NSF/ANSI 61 certification. MMI offers:
- Glass-fused-to-steel — ceramic coating bonded to the steel at 1,500°F+. The most durable option with service life exceeding 40 years. Zero maintenance recoating in most installations. The premium choice for potable water.
- Factory-baked epoxy — high-build epoxy cured in a controlled oven. 15–25 year performance. Cost-effective for budget-sensitive projects with planned recoating intervals.
- Galvanized + epoxy overcoat — dual-system protection for aggressive environments or extended warranty requirements.
Exterior coatings include baked-on polyester, epoxy, or urethane systems in standard or custom colors.
Codes and Standards
- AWWA D103 — Factory-Coated Bolted Carbon Steel Tanks for Water Storage
- NFPA 22 — Water Tanks for Private Fire Protection
- NSF/ANSI 61 — Drinking Water System Components (coating certification)
- ASCE 7 — Seismic and wind loads
- FM Global — Property loss prevention requirements (fire tanks)
- State drinking water regulations — varies by jurisdiction
Bolted Water Storage Tank FAQ
How long does a glass-fused-to-steel coating last in potable water service?
Glass-fused-to-steel coatings routinely last 40+ years in potable water with minimal maintenance. The ceramic bond does not delaminate, peel, or chalk like organic coatings can over time.
What is the largest bolted water tank MMI can build?
We have engineered and erected bolted water tanks exceeding 3,000,000 gallons. Maximum practical size depends on site footprint and foundation conditions.
Does MMI handle the foundation?
Yes. Our foundations team designs and pours ringwall and slab foundations. Single contract for foundation + tank + coating.
Can a bolted water tank be expanded later?
Yes. Additional shell rings can be added to increase capacity. This is one of the key advantages of bolted construction for growing water systems.
Does MMI build fire water tanks to NFPA 22?
Yes. We engineer and erect NFPA 22-compliant fire water storage tanks in bolted construction, sized to your fire flow and duration requirements. Read our fire protection water guide →
Request a Quote
David Mann — Bolted Tank Manager
📞 (417) 540-5349 · 📧 dmann@mmitank.com
