Home » Market Vegetables » KPI 4-Measuring water use
Why it’s Important
With the need for innovations to adapt to climate change and to conserve water, irrigation provides opportunities to produce maximum yields and the potential for environmental protection. Few irrigators use flow meters to track their water use.When it is tracked, it’s usually at the main pump and there may not be good records on which crops/fields have received which amounts of water. It’s valuable to have a good grasp on how much water is being used for irrigation, either total use or use per crop.
Simple methods to measure irrigation water use include:
- Use a flow meter to measure irrigation amount separate from household and livestock use.
- Set pails in a grid pattern in your field to measure amount of sprinkler irrigation water.
- As an alternative to a flow meter, install an hour meter so you know exactly how long the pump is operating. This will eliminate the guesswork of remembering when you turned the pump on and off.
- If using drip irrigation, place cups under several drippers and measure water use over 5 minutes. Be sure to place cups under the dripper furthest from the pump and closest to the pump where water pressure will be the lowest and highest respectively. Prior to measuring, your system will need to be up and running to establish a regular flow.
- Or, if you know your drippers should provide X liters of water/hr, count the number of drippers per line and multiply that by number of rows of drip line.
Lets get started
Use the worksheet below to estimate your gross water use or water use per crop.
Making Improvements
OMAFRA recommends several strategies for improving productivity through irrigation:
- Be aware that irrigation needs will be different depending on the type of soil and vegetable crop. Water needs will be greater at critical stages for different crops.
Critical irrigation periods are listed below for several crops1:
| Critical Period | Crop |
|---|---|
| Flowering, pod setting | snap beans |
| Head formtation and enlargement | broccoli, cabbages, cauliflower |
| Tasseling, pollination, ear filling | sweet corn |
| Flowering, fruit set and development | cucumbers, muskmelons, zucchini |
| Bulb formation and enlargement | onions |
| Flowering, fruit set and enlargement | eggplant, peppers, tomatoes |
- Know your water budget per crop. Water budget is used to track water entering and leaving the system. In a water budget, the crop root zone is visualized as a reservoir of available water. Two things add to the reservoir: rainfall and irrigation. Water is removed from the reservoir through crop water consumption. The grower manages the water budget like a bank account. Irrigation and rainfall are deposits to the account, and daily crop water use is a withdrawal from the account. Available soil moisture stored in the root zone represents the balance in the account.
http://www.omafra.gov.on.ca/english/crops/facts/08-011.htm
- Schedule irrigation based on a good knowledge of crop water needs for each stage of development from seedling to mature crop.
- Schedule irrigation according to rainfall. Monitor rainfall at the field with a rain gauge.
- Schedule irrigation according to evapotranspiration (the transport of water into the atmosphere from surfaces, including soil (soil evaporation), and from vegetation (transpiration)). Monitor evapotranspiration from weather service or on-farm weather station.
- Develop a good knowledge of soil moisture-holding limitations (laboratory test for soil moisture-holding ability or texture analysis).
- Measure soil moisture by the hand-feel method.
- Measure soil moisture with a soil moisture gauge.
- Maintain and increase soil organic matter (as measured by a soil test):
- Use a good crop rotation, including forages if possible.
- Add organic matter.
- Leave residue on soil surface.
- Reduce number of tillage passes.
- Plant cover crops.
- Avoid and reduce soil compaction:
- Stay out of wet fields.
- Reduce axle weight and tire pressure.
- Use a good crop rotation, including forages, if possible.
- Leave residue on soil surface.
- Plant cover crops.
If you use 50,000 litres/day or more of water through irrigation, you are required to have a Permit to Take Water. As part of your permit, you are required to record and submit records tracking daily water use.
Visit the following link for more information:
Goal Setting
Please create an account to access the goal setting section. This will allow you to login at anytime in the future so you can evaluate how you’ve progressed. You will be given examples of steps you can take to help reach your goal, and will have the opportunity to indicate what your steps will be. Be sure to upload your completed KPI forms in order to access them in the future.
1http://www.omafra.gov.on.ca/english/crops/facts/info_irrigation.htm
“Simple technology like putting a misting system in your greenhouse so you don’t have to spend 2 hours per day in the spring to water can have a big impact”
– Amanda Bilek, Owner
Chilligo Creek Farm
“Even something simple like adding wheels to greenhouse tables can save on labour. The tables can be rolled outside for hardening off in the spring, instead of carrying trays out individually.”
– Amanda Bilek, Owner
Chilligo Creek Farm
“Look at the weather forecast for market day. If it’s going to rain all day on Saturday, sales will go down. If you can, delay harvesting and bring less product to the market that day.”
– Amanda Bilek, Owner
Chilligo Creek Farm
“Recent research on processing tomatoes in Ontario has shown yield increases of up to 81% on a range of soil types with the use of properly scheduled irrigation.”
– OMAFRA
“It’s very important to measure water use. Few irrigators use flow meters to track their water use. The natural tendency of growers in Ontario is to under irrigate. When growers do a better job of tracking water use, they tend to use more water but productivity increases. So amount of water used per unit produced may actually decrease.”
– Rebecca Shortt Engineer, Water Quantity, OMAFRA
Additional Resources:
http://www.agrability.org/wp-content/uploads/2016/05/Small-Farm-Guide-to-Purchasing-Equipment.pdf
https://www.bdc.ca/en/articles-tools/employees/pages/default.aspx
Software Helps with Labour Tracking: https://www.fruitandveggie.com/companies/croptracker-welcomes-ontario-berry-growers-association-20292
http://www.omafra.gov.on.ca/english/busdev/facts/16-025.htm
http://www.omafra.gov.on.ca/english/livestock/urbanagbib/sellingyourproducts.htm
www.omafra.gov.on.ca/english/engineer/irrigation.htm
http://www.farmfoodcareon.org/wp-content/uploads/2017/08/Measuring-Water-Fact-Sheet.pdf
http://www.farmfoodcareon.org/wp-content/uploads/2017/08/Self-Assessment-Irrigation.pdf
Ontario CSA Farm Directory: http://csafarms.ca/wp/
Local Food and Farm Co-op Ontario: https://www.localfoodandfarm.coop/
Ontario Farm Fresh Marketing Association: http://ontariofarmfresh.com/about-us/
http://smallfarmcanada.ca/2014/understanding-regional-food-hubs/