The 6,600-gallon water tank is large-scale potable storage — 144 inches across and 101 inches tall, a twelve-foot-wide forest-green cylinder holding over thirty tons of water when full. The green pigment blocks light to suppress algae while blending into landscaping, and the FDA-compliant resin keeps the water drinkable.

Specifications at a Glance

Every figure below is pulled straight from the live product record for this exact tank — the same data on the product page, so what you read here and what you buy never disagree.

Manufacturer	Norwesco
Manufacturer Part #	N-44119
Nominal Capacity	6600 Gallons
Footprint (Diameter)	144"
Overall Height	101"
Empty Weight	998 lb
Material	Polyethylene (HDPE)
Color	Green
Rated Specific Gravity	1.1
Certifications	FDA Approved, UV Stabilized
Warranty	3 Year
Shipping	OVS

Standards & Materials

ASTM D1998 — Standard Specification for Polyethylene Upright Storage Tanks. Governs wall-thickness and hydrostatic design for vertical rotomolded poly tanks of this class.
FDA 21 CFR 177.1520 — Olefin polymers. The food-contact regulation the FDA-grade resin in this tank is compounded to meet.
Specific gravity rating 1.1 — the tank is engineered for liquids up to 1.1× the density of water (water is about 8.34 lb/gal). Confirm your fluid’s SG before storage.

Product Overview

At sixty-six hundred gallons this is the size for serious water security: a rural household riding out long well outages, a small community system, a livestock operation, or a fire-protection reserve. It stands just over eight feet tall on a twelve-foot base — a broad, low, intensely stable cylinder that puts its enormous weight over a large footprint and drains cleanly under its own water column.

It's rotomolded by Norwesco as one seamless piece of virgin linear polyethylene, with no seam or weld across its twelve-foot width, and the resin is FDA compliant for potable water and food-grade contact. At this scale the seamless construction matters: there's no fabricated joint to fail under thirty-plus tons of water, and no crevice to harbor biofilm in a large drinking-water reserve. The wall is rated to a 1.1 specific gravity, which covers water at 8.34 pounds per gallon with margin.

The forest-green color is doing real work. Like black, it's opaque enough to block the light that fuels algae, keeping a large stored volume clearer with less cleaning — but green blends into a landscaped or wooded setting far better than a stark black or white tank, which matters when a twelve-foot cylinder is sitting in view of a home. Empty weight is 998 pounds; filled with water it loads the pad with roughly 61,546 pounds, over thirty tons distributed across the 144-inch base. Maximum service temperature is 120°F.

Plumbing is sized for the volume: a 2-inch NPT outlet for strong flow, plus a 1.5-inch NPT inlet fitting included. The 22-inch lid is large enough for generous fill and vent connections and man-access to inspect a tank this size. Norwesco's 3-year warranty applies. Because of its dimensions it ships via dedicated freight carrier — contact us for delivery timeline and site-access requirements.

Technical Drawing

Official Norwesco technical drawing — 6600 Gallon Plastic Water Storage Tank

Key Features and Specifications

6,600-gallon capacity — sized for safe potable water storage
Constructed from virgin linear polyethylene (HDPE) with 1.1 specific gravity rating — handles liquids up to 9.2 lbs/gal
101" tall x 144" diameter — compact vertical footprint
998 lbs empty, approximately 61,546 lbs when full at rated specific gravity
2 NPT outlet fitting — factory installed and leak-tested
1.5 NPT inlet fitting included
22" lid opening for fill, venting, and interior access
FDA approved for potable water and food-grade liquid contact
3 Year Warranty from Norwesco against manufacturing defects
Forest green color blends naturally with landscaping for residential and agricultural installations
Rated for continuous service up to 120 F / 48 C
Seamless one-piece rotational molding — no seams, no welds, no leak points
Manufactured by Norwesco — a leading name in rotomolded polyethylene tanks
Large tanks require professional installation. Ensure the pad is level within 1 inch across the full diameter and that all piping connections allow for thermal expansion
Ships via dedicated freight carrier due to oversized dimensions — contact us for delivery timeline and site access requirements

Installation and Setup Guide

A thirty-ton full water tank is a real foundation project, but the wide, low geometry is forgiving of tilt and tipping — the work is in the pad and in planning the freight set of a twelve-foot shell.

Site Preparation

Build an engineered base sized for the full thirty-plus-ton load across the 144-inch footprint. While the wide base spreads the weight, the total mass demands a properly specified pad — a substantial reinforced concrete slab or an engineered compacted base — level within an inch across the full diameter. The subgrade must be uniformly compacted so the broad base doesn't settle unevenly. Choose a well-drained site and allow generous perimeter clearance for the freight set, plumbing, and inspection.

Placement and Connections

Connect the included 1.5-inch inlet to your fill source and the 2-inch outlet to your distribution pump or gravity line. Use flexible connections at both fittings — even a stable wide tank breathes with temperature, and a thirty-ton tank makes a rigid-connection failure a major event. The 22-inch lid sits eight feet up, so plan a platform or ladder for safe fill and inspection access. Keep all piping runs clean and supported independently of the tank.

Venting

A large tank exchanges a big air volume during fill and draw. Fit a screened vent in the 22-inch lid sized generously to your peak flow — an undersized vent during a fast fill or a high-demand draw can pressurize or pull vacuum on even a robust wide body. The screen also keeps insects, debris, and animals out of a large potable reserve, which is essential at this scale.

Maintenance and Long-Term Care

At sixty-six hundred gallons, maintenance protects both the structure and a large drinking-water inventory. The green wall suppresses algae, but a reserve this size warrants disciplined, scheduled attention.

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Quarterly Inspection Checklist

Water quality: Inspect through the 22-inch lid for clarity, sediment, or any growth. The opaque green tank blocks light, so growth usually signals a compromised vent screen or lid seal admitting light or contaminants — investigate promptly given the volume at stake.
Base and settlement: Walk the 144-inch perimeter checking that the broad base sits evenly with no low edge, gap, or washout. Differential settlement is the main structural risk for a wide heavy tank.
Fittings: Check the 2-inch outlet and 1.5-inch inlet for weeping — at this scale even a slow seep is a significant loss.
Vent and screen: Confirm the large vent is clear and the screen intact.

Cleaning and Sanitizing

Sanitize the tank at least annually. At sixty-six hundred gallons this is a planned operation: drain the tank, scrub the interior through the 22-inch lid (confined-space precautions apply for any entry), then sanitize the walls and fittings with a chlorine solution — about a quarter cup of unscented household bleach per 15 gallons used — let it dwell, then drain and flush with fresh water until no chlorine odor remains. Clearing biofilm from a large reserve keeps the whole supply safe to drink.

UV and Weather

Green polyethylene is well UV-stabilized for long outdoor life and blends into a landscaped setting. Inspect exposed faces yearly for chalking. A large stored volume changes temperature slowly, which moderates swings, but in hot climates the dark-green wall absorbs heat — partial shade helps if water temperature matters for your use.

Alternatives and Comparisons

For a reserve this large, the choices are color and consolidation:

Forest green versus black or a lighter tank: green and black both block light to control algae; green simply hides better in a yard or wooded setting, which is often the deciding factor for a twelve-foot tank near a home. A lighter tank shows the level through the wall but admits light that feeds algae — not ideal for a large stored reserve.

One 6,600 versus several smaller tanks: consolidating into one tank means a single foundation and fewer fittings to maintain; multiple smaller tanks let you isolate part of the supply for cleaning without losing the whole reserve. For water security, some operators keep two tanks so one can always stay in service.

Frequently Asked Questions

How long will the 6600 Gallon Plastic Water Storage Tank last?

Fifteen to twenty years is realistic with an engineered, level base and normal use. Green polyethylene is well UV-stabilized, and the seamless wall has no joints to fail, so a large water tank typically delivers excellent service life. Foundation performance and routine sanitizing are what carry it to the upper end of the range.

What chemicals can I store in this tank?

This is a potable water tank — FDA compliant for drinking water and food-grade liquids, rated to a 1.1 specific gravity for water and benign aqueous solutions up to about 9.2 pounds per gallon. It is not intended for aggressive chemicals, fuels, or solvents; for those, use a tank rated to a higher specific gravity and verified for the chemistry. Keep this one dedicated to water and water-based use.

What kind of foundation does a 6600-gallon tank need?

It needs an engineered base — a substantial reinforced slab or engineered compacted pad — sized for roughly 61,546 pounds across the 144-inch footprint, level within about an inch, on uniformly compacted subgrade. The wide base spreads the load, but thirty-plus tons demands a properly specified, non-settling foundation. Differential settlement is the main thing to design against.

Does this tank come with a warranty?

Yes — Norwesco's 3-year warranty covers defects in materials and workmanship. It excludes inadequate or uneven foundations, freezing damage, and impact damage. At this scale, retain documentation of the engineered pad for any claim.

Can I install this tank underground?

No — this is an above-ground water tank not engineered for burial, and a tank this size would be impractical to bury regardless. Soil pressure would deform the wall. For below-grade water storage, use a purpose-built underground cistern designed for soil load.

Buying Considerations

Buying at this scale is project planning. Confirm an engineered base for thirty-plus tons is in your scope, and a well-drained site for a twelve-foot footprint. The included 2-inch outlet and 1.5-inch inlet make it ready to plumb into a distribution system. If hard freezes occur in your area, plan freeze protection for the plumbing and consider that a large reserve resists freezing solid but exposed fittings remain vulnerable. This ships by dedicated freight carrier — call us to coordinate delivery and confirm you have the equipment and access to set an 1,000-pound, twelve-foot shell.