A 275-gallon retired food-grade IBC tote can be converted into a rainwater catchment system for roughly the cost of one off-the-shelf 55-gallon rain barrel. It stores five times the water on roughly the same footprint. Once you have seen one in service, the math sells itself. Here is what we have learned helping a dozen schools, eight community gardens, and several small farms put these together.
Source the tote correctly
Use a food-grade tote. The catchment is for plants, but plants take it up and you (or your students) may drink the produce. A tote that previously held syrup is fine; a tote that previously held degreaser is not. Pay the extra few dollars for documented food-grade.
Plumbing the discharge
The factory 2″ buttress valve is your friend. Step it down to 3/4″ garden hose thread with a single brass adapter. At full water column you will see ~4–6 PSI at the spigot, which is plenty for drip irrigation and soaker hose.
For pressurized sprinkler service, add a 1/2-HP transfer pump. Northern Tool sells acceptable ones in the $120 range.
The overflow port
A 275-gal tote will overflow in a heavy summer storm faster than you expect. Drill a 2″ bulkhead in the upper sidewall, route it to whatever is downhill — a French drain, a swale, a second tote. Do not let the overflow back up to the fill cap; it will lift the cap and discharge from the top.
Algae and UV
HDPE is mostly opaque but not perfectly so. In direct summer sun an uncovered tote will grow algae within three weeks. Options:
- Shade with a tarp or built shelter. Cheapest.
- Paint the exterior with light-colored exterior latex. Use light colors to limit thermal gain.
- Wrap with reflective insulation. Most expensive, best result.
Mosquitoes
Cover the fill port with a fine mesh (no larger than 0.5 mm). Mosquitoes will find any gap and the tote will become a hatchery within a week.
Cold-climate care
In Wisconsin winters, drain totes by Halloween or insulate them. A frozen tote is usually fine — HDPE has the ductility to handle one or two ice cycles — but the cage and pallet often suffer, and a sustained ice column can pop the fill cap.
Multi-tote arrays
Two totes in series, manifolded at the discharge, double your storage with a single fill point. Three or four start to require thoughtful manifold design. Beyond six, talk to us.