IBC Totes for Rainwater Harvesting: A Complete Setup Guide

Why Harvest Rainwater in Utah?

Utah is one of the driest states in the nation, receiving an average of just 13 inches of precipitation per year statewide — well below the national average of 30 inches. Water is precious here, and every drop that runs off your roof and into the storm drain is a missed opportunity. Rainwater harvesting captures that runoff and puts it to productive use: irrigating gardens, watering livestock, washing equipment, and reducing your dependence on municipal water supplies.

An IBC tote is one of the most practical and cost-effective containers for residential and small commercial rainwater harvesting. A single 275-gallon IBC holds enough water to irrigate a large garden for a week or more, and the built-in valve makes dispensing effortless. In this guide, we will walk through every step of setting up an IBC-based rainwater harvesting system — from legal considerations to winterization.

Legal Considerations in Utah

Utah has a unique legal framework around water rights, and it is important to understand the rules before you start collecting rainwater. As of the current law:

• Underground storage: You may collect and store rainwater in underground containers up to 2,500 gallons without registration.
• Above-ground storage: You may collect rainwater in above-ground containers totaling up to 2,500 gallons, but you must register with the Utah Division of Water Rights. Registration is free and can be done online.
• Use restrictions: Harvested rainwater must be used on the property where it is collected, primarily for outdoor irrigation and similar beneficial uses.

For most homeowners, 2,500 gallons is plenty — that is approximately nine 275-gallon IBCs. The registration process takes about five minutes online and ensures you are in compliance with state law. The relevant statute is Utah Code Section 73-3-1.5, and the Division of Water Rights website has the registration form.

How Much Rainwater Can You Collect?

The amount of rainwater you can harvest depends on your roof area and local rainfall. The formula is straightforward:

Gallons collected = Roof area (sq ft) x Rainfall (inches) x 0.623 x Collection efficiency

The 0.623 factor converts square feet and inches to gallons. Collection efficiency accounts for losses from evaporation, splash, first flush diversion, and gutter overflow — typically around 0.75–0.85 for a well-designed system.

Let us run a real-world example for Salt Lake City:

• Average annual precipitation: approximately 16 inches (Salt Lake City proper receives more than the state average due to lake-effect moisture).
• Roof area: 1,500 sq ft (a modest single-story home).
• Collection efficiency: 0.80.
• Annual harvest: 1,500 x 16 x 0.623 x 0.80 = approximately 11,950 gallons per year.

That is nearly 12,000 gallons — more than enough to water a substantial garden through the growing season, especially when combined with strategic storage. Even a single 275-gallon IBC will capture the runoff from a moderate rain event on a portion of your roof.

Choosing the Right IBC for Rainwater

Not all IBCs are created equal for rainwater harvesting. Here is what to look for:

• Food-grade preferred: A food-grade IBC has only ever held food-safe products, so there is no risk of chemical contamination leaching into your water. While you probably will not be drinking rainwater (it requires additional treatment for potability), food-grade totes give you the cleanest possible starting point, especially if you are watering edible gardens.
• Opaque or wrapped: Sunlight promotes algae growth in stored water. Choose a white IBC and wrap it in opaque material (landscape fabric, shade cloth, or even a plywood enclosure) to block light. Some IBCs are manufactured with UV-stabilized black or dark bottles, which are ideal but less common.
• Good structural condition: The cage should be straight and the pallet solid, since a full IBC weighs over 2,400 lbs and needs a stable base.
• New valve: A reconditioned IBC from Salt Lake IBC comes with a new valve, which ensures a leak-free seal. If you buy a used tote from another source, plan on replacing the valve yourself ($10–$20).

Step-by-Step Setup Guide

Step 1: Choose Your Location

Place the IBC adjacent to a downspout from your gutter system, on a level, stable surface. A concrete pad, compacted gravel bed, or paver stones all work well. The surface must support the full weight — over 2,400 lbs for a full 275-gallon IBC. Soil or grass will compact and shift under that weight, causing the IBC to lean or sink. Elevating the IBC on concrete blocks or a sturdy platform gives you more head pressure at the valve and makes it easier to fit a watering can or bucket underneath.

Step 2: Prepare the IBC

If the IBC has a standard 6" or 8" fill opening, you have two options for connecting the downspout:

• Direct connection: Cut a hole in the top of the IBC (or enlarge the fill opening) to match your downspout diameter (typically 2x3" or 3x4" rectangular, or 3" or 4" round). Install a downspout adapter fitting and seal with silicone caulk. Cover with a fine mesh screen (1/16" or smaller) to keep debris and mosquitoes out.
• Flexible downspout diverter: Install a diverter kit on the downspout that redirects water into a flexible hose running to the IBC fill opening. This is a cleaner installation that does not require cutting the IBC and allows you to disconnect the IBC easily for maintenance. Diverter kits are available at hardware stores for $20–$40.

Step 3: Install a First Flush Diverter

This is the most important — and most commonly skipped — component of a quality rainwater system. A first flush diverter captures and discards the first 10–20 gallons of runoff from each rain event. This "first flush" contains the highest concentration of contaminants — bird droppings, pollen, dust, leaves, roofing material residue, and atmospheric pollutants — that have accumulated on your roof since the last rain.

A simple DIY first flush diverter is a vertical section of 3" or 4" PVC pipe, capped at the bottom with a slow-drain fitting (a 1/16" hole or a drip irrigation emitter). The pipe is installed between the downspout and the IBC inlet. When rain begins, the first water fills the diverter pipe (size it for 1–2 gallons per 100 sq ft of roof area). Once the pipe is full, a floating ball or simple tee fitting diverts the now-cleaner water into the IBC. The diverter pipe slowly drains between storms through the bottom orifice, resetting itself for the next event.

Step 4: Install an Overflow

Your IBC will eventually fill up, and you need a safe path for excess water. Install an overflow fitting near the top of the IBC — a bulkhead fitting with a short section of pipe or hose that directs overflow water away from your foundation. A 2" or 3" fitting provides enough capacity to handle the inflow rate from a heavy storm. Direct the overflow to a garden bed, a dry well, or back into the storm drain system.

Critical point: Cover the overflow opening with mesh screen to prevent mosquitoes from entering the IBC through this route. Mosquitoes can breed in standing water, and an uncovered overflow is an open invitation.

Step 5: Set Up Dispensing

The existing 2" bottom valve on the IBC is your primary dispensing point. For garden irrigation, you have several options:

• Garden hose adapter: Install a 2"-to-3/4" adapter on the valve outlet, then connect a standard garden hose. Flow will be gravity-fed, so pressure will be low (about 1–2 PSI depending on elevation), but it is adequate for drip irrigation, soaker hoses, and filling watering cans.
• Drip irrigation: Connect a drip irrigation mainline directly to the adapter. Gravity-fed drip systems work well with IBCs — just make sure to use pressure-compensating emitters rated for low pressure (3–5 PSI or lower).
• Small pump: For applications requiring more pressure (sprinklers, long hose runs), install a small 12V or 120V utility pump. A pump rated for 5–10 GPM at 20–40 PSI is more than adequate for residential garden irrigation from an IBC.

Step 6: Optional — Add Filtration

For garden irrigation, filtration is not strictly necessary — plants are not picky about water clarity. However, if you want to extend the life of drip irrigation emitters (which can clog with sediment) or use the water for washing, a simple inline sediment filter (50–100 micron) installed after the valve will remove particulates. These filters cost $15–$30 and use replaceable cartridges.

For non-potable household uses (toilet flushing, laundry), a more robust filtration system including sediment, carbon, and UV stages is recommended. For potable (drinking) water use, a full treatment system including sediment, carbon, and UV or reverse osmosis is required, and this is beyond the scope of a basic IBC setup.

Daisy-Chaining Multiple IBCs

If one IBC is not enough storage, you can connect multiple IBCs together in a daisy chain configuration. The principle is simple: connect the overflow outlet of IBC #1 to the fill inlet of IBC #2, the overflow of IBC #2 to the inlet of IBC #3, and so on. Water fills the first IBC, overflows into the second, and so on down the line.

For the best results:

• Install the connecting pipes near the top of each IBC (within 2–3 inches of the maximum fill level) so each tote fills to capacity before overflowing to the next.
• Use 2" or 3" pipe for the connecting lines to ensure adequate flow during heavy rain.
• Keep all IBCs at the same elevation for even filling. If one IBC is lower than the others, it will fill first and potentially overflow before the upstream IBCs are full.
• Alternatively, connect them at the bottom using a manifold pipe. This creates a communicating vessels system where all IBCs fill and drain equally. This approach is more complex to plumb but gives you more even water distribution and allows you to draw from any tote's valve.

Four 275-gallon IBCs daisy-chained together give you 1,100 gallons of storage — a serious water reserve for garden irrigation, and still well within Utah's 2,500-gallon registration limit.

Winterization in Utah

Utah winters are cold, and water expands approximately 9% when it freezes. A full IBC that freezes solid can crack the HDPE bottle and damage the cage. Winterization is not optional — it is essential.

You have two approaches:

• Drain the system: Before the first hard freeze (typically late October to mid-November along the Wasatch Front), drain the IBC completely, disconnect the downspout diverter, and leave the valve open so any residual water can drain out. This is the simplest and most reliable approach for seasonal rain barrels.
• Insulate and heat: If you want to maintain water storage through winter (for livestock watering, for example), you can insulate the IBC with rigid foam board, fiberglass batts, or straw bales, and install a submersible stock tank heater or heat tape to prevent freezing. This adds cost and complexity but can be worthwhile for agricultural applications.

Never leave a full, uninsulated IBC outdoors through a Utah winter. Even a partially full IBC can sustain freeze damage if the water level allows ice to expand against the walls of the bottle. Drain it, protect it, and it will serve you for many years.

Ongoing Maintenance

A rainwater harvesting IBC requires minimal but regular maintenance:

• Monthly: Check the mesh screen on the inlet and overflow for debris. Clear any leaves, twigs, or insect nests.
• Quarterly: Inspect the valve for drips and the fittings for leaks. Tighten or replace gaskets as needed.
• Annually (spring): Drain the IBC completely, scrub the interior with a long-handled brush and a mild bleach solution (1 tablespoon of bleach per gallon of water), rinse thoroughly, and refill. This prevents algae and biofilm buildup.
• Annually (fall): Winterize as described above.
• As needed: Check that the light-blocking wrap is intact. Replace any UV-degraded fittings or adapters.

"Rainwater harvesting with IBC totes is one of the most rewarding DIY projects for Utah homeowners. It saves money, conserves water, and connects you to the natural water cycle in a tangible way. And it is remarkably easy to set up." — Salt Lake IBC Team

Salt Lake IBC sells food-grade and economy-grade totes specifically selected for rainwater harvesting at our Woods Cross facility. We also carry valves, adapters, garden hose fittings, and mesh screens — everything you need to build your system in a single stop. Come visit us and we will help you size your system, choose the right totes, and get set up for your first season of free water from the sky.