The City of Calgary is creating a blanket water restriction bylaw that will negatively impact the health of your expensive trees & shrubs. (grass will go dormant without water, trees & shrubs will die).
Background:
As part of a drought management plan, the Province has requested all municipalities to voluntarily reduce water use by 5% to 10% and for all stakeholders to equally share in that responsibility. We agree that our industry needs to do its part. However, the City of Calgary is choosing to mandate an 85% to 90% reduction in outdoor watering (a 2-hour water window twice per week) without acknowledging the effectiveness of the bylaw or the impact on residents and businesses. Why? Because it provides the perception of action. Unfortunately, there is very little impact on river flow, reducing water consumption, or improving drought resiliency.
The Problem:
- Time-Based Water Restrictions
- Do not follow best horticultural practices of deeper, less frequent watering.
- Do not promote effective water use.
- Do not achieve conservation objectives.
- Result in massive amounts of run-off and waste.
- Poor City Planning
- The most important water conservation initiative in any landscape construction is topsoil. The more moisture held within the soil profile, the greater the opportunity to reach the next rain event without any supplemental watering. the City of Calgary has no soil depth or soil quality specifications for private development.
- Unlike plumbing and other trades, no minimum design specifications or blueprints are required for new private irrigation installation (outside a few specialized incidents).
Residential Irrigation Analogy to Time-Based Restriction:
Think of your soil like a 100-litre fuel tank that has a 1″ refill opening. Think of your irrigation like a gas pump with a large 2″ filler nozzle. No one would try to fill a 100-litre tank with 200 litres of fuel using a 2″ nozzle (held wide open) held in front of a 1″ opening twice a week every week…especially if the fuel gauge was registering full or nearly full. just like spilling fuel all over the ground will not allow you to drive further, neither will water running off the landscape provide any benefit to plants.
Unfortunately, these analogies do not resonate with municipalities that impose this type of restriction. the behaviour created by such policies is: “If I can’t water tomorrow, I am going to water whenever I can for as long as I can today.”
For larger landscapes, this type of time-based restriction only promotes surface watering with no effective value to plants. in both cases, the results are massive amounts of water waste with no benefit.
The Simple Solution: Eliminate Timer-Based Watering
Rather than taking a proactive approach through education, the City feels it is necessary to mandate your behavior. We can all reduce water use up to 50% to 60% (well above the request from the Province) by doing the following:
- Option 1 : Automated Solution – Smart Control:
- For decades, many residents and businesses have been utilizing Smart Irrigation Control Systems and have voluntarily saved billions of litres of water each year. These systems automatically adjust watering schedules based on real-time ET Weather and Effective Rainfall measurement, site-specific soil and micro-climate conditions to only water the landscape when the soil moisture is depleted, and it hasn’t rained. If you are taking this proactive approach, tell the City what you are doing already.
- Option 2: Manual Option:
- Eliminate Timer-Based Watering. Water each area of the landscape independently and only when the plants show signs of stress, not because it is Monday, Wednesday, or Friday. Follow the same principle for outdoor plants as is done with indoor plants. Plants are healthier when the soil is allowed to dry out and there is good soil oxygenation. Deficit watering promotes root growth, healthier plants, and eliminates water waste.
- Set a Cycle & Soak Program. Ensure the moisture applied to your landscape is absorbed within the soil while eliminating run-off waste (e.g., set spray head sprinklers to water 3 short cycles of 4 minutes with a break in between, rather than one long cycle of 20 minutes. This reduces total water used and run-off).
- Stop Watering When the “Tank” is Full. Evaluate how much water is required to refill your soil profile and stop irrigating once full (the gas tank analogy). If you are going to use the manual approach, tell the City what you will do to contribute.
Perspective:
If irrigation was completely eliminated in Calgary, there would be very little improvement in river flow on either the Bow or Elbow River. When the City implemented Water Restrictions from August 14, 2023, to October 31, 2023, the flow rate on the Bow River was 75 m³ per second. The irrigation industry responded by turning off most commercial, multi-family, and residential irrigation systems (under our control). The net result posted by the City was 1.5 billion litres of water saved over the entire period. This was a net flow reduction of only 0.217 m³ per second on the Bow River. Every little bit helps but this was a drop in the bucket compared to how landscape irrigation is being targeted as the primary problem.
