Published by Communications and Public Affairs (519) 824-4120, Ext. 56982 or 53338
June 03, 2003
Prof harvesting rain to keep gardens green, reduce water use
A University of Guelph professor has teamed up with a local couple to study a new rainwater harvesting and garden irrigation system designed to reduce municipal water use.
Maurice Nelischer, School of Environmental Design and Rural Development, is using the home of Richard and Norah Chaloner as a test site. He hopes to refine a relatively low-tech system of rain barrels and drip irrigation to allow homeowners to keep their gardens green without straining municipal waterworks.
The trial will provide a first-ever look at the feasibility of a rainwater collection and distribution system for Guelph-area gardens. “There are no data on rainwater harvesting in this climate,” said Nelischer, who recently returned from a two-year teaching stint in California, where homeowners are required by law to use only drip irrigation.
He is investigating the system in partnership with the City of Guelph and the Guelph International Resource Centre (GIRC). Concerns about water use prompted city officials to approach U of G this year for help in studying ideas for conservation. “Cutting back on water should be something we aim for,” said Martin Lavictoire, the city’s sustainability program co-ordinator. “The less we use, the more we have for the future.”
Residential water use in Guelph increases in summer by about one-third, an increase attributed largely to gardeners, Nelischer said. Add in the past two summers’ worth of drought conditions that have led to extended outdoor watering bans, and it’s no surprise that ideas for conserving water have caught on. “It’s easier to save water than find new sources,” he said.
That’s the feeling of the Chaloners, whose extensive perennial and vegetable gardens have become an outdoor lab for the U of G landscape architect. “We’re both very concerned about protecting the environment, and we’re concerned about dwindling water reserves,” said Richard Chaloner. “If we can keep our garden going without using city water, all the better.”
The trial system was assembled in two locations in the Chaloner’s backyard this spring. On one side of the house, modified downspouts will feed water from the eavestroughs into a trio of modified plastic pickle barrels connected to each other by plastic tubing. A similar setup will collect runoff water from the roof of a sizable garden shed behind the house. Each barrel holds 55 gallons. Mesh screens over openings at the top keep out debris and insects, including mosquitoes looking for breeding sites in standing water.
The idea of collecting rainwater for garden irrigation is hardly a new one. During the past five years, GIRC has sold more than 2,000 rain barrels to city residents. But yoking together three barrels is a new step. Also novel is the idea of marrying rainwater collection with a gravity-fed drip irrigation system. Currently, rain barrel users have to scoop water into pails or cans to irrigate their gardens. With this system, a tube attached to one of the barrels feeds into an array of micro-tubules snaking out in different directions across the garden, allowing for direct irrigation of perennial beds and even individual plants.
Nelischer hopes to learn whether the system will collect enough rainwater to keep the garden lush all summer and to determine the optimum number of containers to use. Data loggers attached to the hoses will collect information that he’ll upload to his laptop computer to measure quantity and rate of collection and use, as well as overall efficiency of the system. A separate rain gauge mounted on the shed roof will allow him to compare collection and use against actual rainfall. Graduate student Yvonne Cardoso will help with the project, including collecting samples to be tested by the city for water quality.
For media questions, contact Communications and Public Affairs: Lori Bona Hunt, (519) 824-4120, Ext. 53338, or Rachelle Cooper, (519) 824-4120, Ext. 56982.