Farmers catching and managing rainwater to feed the crops

Jul 28, 2020

Oceanside Farms on East End Road.
Credit Oceanside Farms

The third vital ingredient involved in making things grow, along with sunshine and good soil, is water. And around Homer, growers do their best to manage rainfall and snowmelt to avoid having to have water delivered. Some go so far as to catch and save rain, and at least one famer on East End Road built a pond to help store the water that he collects.
    On this week’s “Homer Grown,” host Desiree Hagen spoke with Don McNamara, co-owner and operator of Oceanside Farm about his extensive catchment system.
    “Our high tunnels are on a five degree slope and we have roll up sides. And so instead of rolling up the sides inward, as the manufacturer recommends, we rolled them outwards and that made a gutter down the whole 70 foot length of the high tunnel. And then we run it into a four inch PVC pipe and tie it altogether tying into a thousand gallon tank at the bottom of the Hill,” McNamara said. “That's all gravity fed. And then we have a pump at the tank and that runs into another pump, which runs up the Hill. So it's quite a (Rube) Goldberg operation if you want the truth, but it's working for us.”
    McNamara said the roofs of his four high-tunnel greenhouses can harvest about 600 gallons of water from an inch of rain.
    Like many growers, McNamara relies heavily on an automatic drip irrigation system.
    “Last year, we ran two miles of pipe around the property. So it might look like spaghetti lines to someone who didn't know, but it's working quite well. We have one pump that puts out from three to 16 gallons a minute, so we can really throw a lot of water anywhere we need rather quickly. We have zones up probably around 5,000 square feet as his own. And we have one, two, three, nine, 10, 11, 12. We have about 12 zones and they take about 200 to 400 gallons, a zone per day.”
    Mike Gracz is a local hydrologist who also has a catchment system installed.
    “And so for around here, get your pencils and paper out, cause if you’re considering doing this, you're going to want to know this. You get a gallon of water per month per square foot of catchment that you have. So that's the footprint of your roof. And I catch off my house in my shed. So I have about 2,000 square feet of catchment, so I can get about 2,000 gallons a month,” Gracz said. “But to get that all year round, I have to have about four times that in storage. So that's about 8,000 gallons of storage, which is a lot of space. You need a lot of space to make it work. And I've had my system for 15 years and I've had maybe six or seven deliveries, one this year two last year. Nevertheless, we get dry periods. And then, you know, before that, I don't think I had a delivery for six or seven years.”
    You can hear “Homer Grown” with Desiree Hagen every other Saturday on KBBI. This week’s show on saving water is posted now online at KBBI.org.