Guide
Catching rain in an IBC tote
One inch of rain on 1,000 square feet of roof yields about 600 gallons, so a 275 gallon tote fills in under half an inch. A tote used for rain should have a documented food-grade history, a screened opening and a plan for overflow.
How much rain a roof sends to a tote
The UF/IFAS rule of thumb is that one inch of rain on 1,000 square feet of roof yields about 600 gallons of collected water. A 275 gallon tote is full in under half an inch on that roof, and a 330 gallon tote is full at about half an inch.
| Tote | Rain to fill it | Roof area for one inch to fill it |
|---|---|---|
| 275 gallon | about 0.46 inch | about 460 square feet |
| 330 gallon | about 0.55 inch | about 550 square feet |
The figures assume no losses to the first flush, splash or overflow, so treat them as the upper end of what a roof delivers.
Why the tote needs a food-grade history
Rainwater from a tote often ends up on vegetables or in a stock tank, and the bottle is the thing it sits in. A tote that held a chemical keeps that history, and the CDC advises not to store emergency water in containers that previously held toxic chemicals, such as bleach or pesticides. It says FDA-approved food-grade containers are best.
A rinse does not change that. Food-grade history describes the paperwork that does. A rinsed chemical tote is not fit for drinking water. UF/IFAS adds that stored rainwater is not for drinking at all.
Screening, overflow and winter
UF/IFAS says openings should be screened against mosquitoes. A tote has two openings that matter: the inlet where the downspout enters and the overflow. Cover both with fine mesh. Keep the fill cap closed when it is not receiving water, and keep the tote out of direct sun to slow algae.
Overflow is the part people forget. A full tote sends the rest of the storm to the ground beside it. Pipe the overflow to a garden bed or drain it away from the foundation. Empty the tote before a hard freeze, because frozen water expands and splits the bottle.
Livestock, irrigation and the Agricultural Reserve
A stock tote is a different use. Texas A&M AgriLife says a 1,000-pound heifer may need about 20 gallons of water a day in hot weather. At that rate a 275 gallon tote is a week and a bit of water for one animal, and a farm sets its tote count by the herd.
Montgomery County's Agricultural Reserve covers 93,000 acres, about a third of the county, and helps retain more than 500 farms. Growers there and in Loudoun are the people the buy side of this site exists for.
Keep reading
- Rain catchmentTotes for catching rain in Montgomery, Loudoun and Frederick gardens and farms: which grade, screening and where the overflow goes.
- Food-grade historyTotes with a documented food-only history, for stock water, irrigation and food use. What the paperwork shows and what it does not.
- RinsedA rinsed tote is emptied and flushed, with the original bottle left in. It is not food or pharma grade. See its uses and limits.
Sources
- Saving and using rainwater (UF/IFAS)
- How to create and store an emergency water supply (CDC)
- Keep cattle hydrated and healthy (Texas A&M AgriLife)
- Agricultural Reserve (Montgomery Planning)
Last reviewed . General guidance, not legal advice.