Agraria Journal Winter 2021

Water for Every Season BY PETER BANE SISKIYOU PERMACULTURE A biochar kiln in use to turn brushy forest fuels into soil amendment 22 AGRARIA JOURNAL 2021 Climate change has made farming a more challenging pursuit than ever before as heating of the atmosphere drives drought, flood, and storms beyond all historic norms. Two broad strategies must become part of every farmer’s toolkit: trees and water catchment. The latter is more immediate, and I address strategies for it below. Trees provide long-term adaptation and also mitigate against the root causes of climate change, which is driven by disruptions to the hydrologic cycle caused by changes in land use, in particular the removal of vegetation from vast areas. These hydrologic disruptions are exacerbated by the release of carbon stored in forests and soils into the atmosphere as CO2, where it joins fossil carbon from the industrial use of coal, oil, and gas. Because rain and snowfall are now more intense and less regular, we have to catch moisture when it falls, and hold it on the land. This both increases water supply and restores balance to the hydrologic cycle at a local scale. START AT THE TOP On a small scale, every roof is a water collection system if it has gutters. This high-quality runoff can be directed to tanks, and from tanks into ponds for use and temporary storage. Especially in flat Midwestern landscapes, the house or barn roof is often the highest point in the local catchment. Intercepting water as it comes off the gutters allows us to direct it to nearby tanks, where it can be stored for high- value uses such as domestic water and drip irrigation. Avoid pumping when you can: place your tanks not far from the building, but on the highest ground available. Take the overflow to ponds if you can. This will preserve the fluid resource for pumped irrigation, firefighting, stock watering, aquaculture, or recreation. At a minimum, create depressions or swales where overflow can be safely absorbed into the ground. CONTROL THE SPREAD A corollary of catching and storing water above ground is the need to distribute it. Every household and farmstead needs a reticulated water system. Ideally, this can switch between sources such as the pumped water from wells and the tank water stored high enough to flow by gravity. The system should have valves that enable this and that separate sections of the system to allow for repair. The irrigation system should work in all seasons, which means it must be protected from freezing, thus with mains laid below the frost line, and accessed by freeze-proof, self-draining yard hydrants or an equivalent. Tanks can be of various forms. Rain barrels are easy to install but hold very little water. A more useful option is the IBC tote, a polyethylene tank between 260-330 gal. capacity in a metal cage with a constructed platform base. Ganged and protected by a hoophouse, these can form the basis for winter cultivation and year-round water in moderate climates. Their thermal mass stabilizes temperatures in a greenhouse or polytunnel. Uncaged polyethylene cylinder tanks and fiberglass and used stainless dairy tanks are available in larger sizes, though site-built