Last year's droughty summer spurs research into water efficiency

Thursday, May 2, 2013

A cluster of research projects is underway in Ontario to help growers make better use of water resources and reduce the risk of losses from drought

by DON STONEMAN

In a machine shop near Alliston earlier this year, workers were busy modifying an arm on a pivot irrigator to allow for variable rates of water to be delivered to potato fields.

Later this growing season, and in another part of the province, the Ontario Tender Fruit Growers Marketing Board will be evaluating soil probes to determine the best way to measure moisture levels for a peach crop. A similar project will measure moisture in the ground under sod fields. There's also testing of systems to manage moisture levels in non-irrigated field crops in Oxford County.

After last year's droughty summer, it is no surprise that Farm & Food Care Ontario is administering a cluster of on-farm research and demonstration projects.

The awkwardly named Water Resource Adaptation and Management Initiative (WRAMI) is a one-year, $900,000 project to develop and demonstrate systems that will improve water use and efficiency, says project manager Bruce Kelly. The money to fund 13 projects, selected from 34 submissions, comes from Agriculture and Agri-Food Canada and the Ontario Ministry of Agriculture and Food.

WRAMI projects are about water conservation and efficiency. Of the total monies, $200,000 has been earmarked for benchmarking projects where specific agricultural sectors look at water use. Two of those projects are for ornamental outdoor container nurseries. While greenhouse flower growing is considered to be relatively water conserving, pot-growing ornamentals outside are deemed to have room for improvement, as does the grape industry.

"Not that many grapes are irrigated. Grapes like it pretty dry, but not as dry as 2011 and 2012," says Kelly. Some growers are considering irrigating and this study will look at techniques used and also water storage. "Irrigation soon leads to issues of water security. It is nice to decide you are going to irrigate, but where are you going to get the water?" Kelly asks rhetorically.

One of the WRAMI projects addresses water security in the Whiteman Creek watershed in Brant County, formerly devoted to tobacco growing and now largely to vegetables. Kelly says Level 1 and Level 2 drought situations, where water takers are asked to voluntarily reduce their uses, are commonly declared in low rain seasons, but the possibility of a Level 3 – essentially a drought disaster when restrictions on water use would be declared – has been hanging over the area for a while. "No one wants to get into whether cherries trump strawberries trump sweet corn," Kelly says.

Growers will be discussing when various crops need water to avoid a disaster, and plans will be developed to make the best use of resources, such as ponds that might otherwise be unused.
The WRAMI projects are about risk management. For some farmers, their best plan is crop insurance, says Kelly. "But if you are part of a packing co-op or a tomato grower who irrigates four out of five years, your relationship with irrigation is different." Failing to deliver a crop is not an option.

Most of the projects were put forward by commodity groups, or in the case of the non-irrigated crops in Oxford, a soil and crop improvement association.  A cell phone app lets a farmer take a picture of his field and determine the percentage of residue cover. Building organic matter in the soil helps preserve moisture. The goal is about 30 per cent. "This will help extension folk and farmers continue the dialogue on soil cover," Kelly says.

The Ontario potato board's experiment with a pivot arm aims to allow different amounts of water to be applied to different soil types. "There is a lot of cross-valving being added to this pivot arm" to change the rates in various zones, Kelly says. "It is an experiment to see if they can use less water to get the same results."

Another potato project involves development of algorithms (mathematical equations) to determine how much irrigated water gets to crop roots.   

A number of projects are connected to soil moisture probes provided by Win Weather Innovations Incorporated in Chatham. Kelly says the company's deep soil probes measure soil moisture at three different depths to a maximum of 30 inches. The probes help producers to decide "when to turn (the irrigation) on and how much water to put on."

The University of Windsor is cleaning water from greenhouses by growing algae and stripping it off to make biofuel. "We have systems that clean up fertilizer waste. This actually makes something from it," Kelly says.

A related project, sponsored by Ontario Greenhouse Vegetable Growers, is a spectrometer that allows analyzing of nutrient solutions in a greenhouse to see if it can be done in-house without the current four-day delay when samples have to be sent out for testing. Greenhouse operators "would use less water if they could make better decisions about their wastewater stream," says Kelly. BF