by Jim Newman — Non-farming irrigation can eat up 50% of the municipal water supply in the cities of Texas, according to the Dallas Water Utilities, and this is not unusual in the United States. The Massachusetts Water Resources Authority reports that, during summer months, water demand increases up to 50%. The lion’s share of this increased demand feeds irrigation systems.
For commercial property owners and managers, these statistics show an opportunity to for significant operational savings from landscaping and irrigation management. While the proportion of operating expenses devoted to landscaping and irrigation in a commercial property falls somewhere between 5% and 10%, the costs of upgrading practice in these categories is quite low. Typical system and practice upgrades have paybacks well under 1 year.
Typical Landscape Costs
Landscape maintenance = $.26 /sf
Pest control = $.07 /sf
Water (landscape share) = $.07 /sf
Total landscape costs = $.40 /sf
IREM statistics for suburban office building in Northeast, 2010.
5-year Return on Investment
50,000 s.f. New England Office Building
Upgrade package cost = $25,000
Savings from upgrades = $10,000/yr
(savings equals 50% of landscape cost)
5-year ROI = 200 %
Reduced Environmental Impact
25% reduction in irrigation water
50% reduction in fertilizer use
Reduce nutrient load in runoff from .031 to .022 = 33%
A typical suburban office building in the Northeast might spend around $0.40 per square foot for irrigation, landscape maintenance, and pest control. Each of these activities has well established practices that can reduce cost. The primary focus for expense reductions should be systematic changes that maintain quality while water use and subcontractor expense are reduced.
A package of upgrades for this typical property might include:
- Reducing high-maintenance landscape, such as lawn areas and other high-maintenance plantings.
- Installing on-site stormwater management and retention features.
- Installing a smart irrigation system.
- Switching to integrated, low-impact pest control.
The overall effect of this set of coordinated changes to how the grounds of the building are managed would not cost a lot to implement, but would pay immediate dividends in lower operating costs, with an added bonus of greatly reducing the environmental impact of the property.
While the reductions in operating expenses are great, the real value of these upgrades may lie in less tangible effects. Lower operating expenses and more stable Net Operating Income allow the building management more room for rent negotiations and more operating cash for maintenance and upgrades, leading to happier and more stable tenants. Less water use, more controlled storm run-off and fewer dangerous pesticides not only reduce environmental impacts, but also make for a happier municipality. More focus on responsibility for water-use reductions and low impact landscaping can give the building management staff a stronger sense of responsibility and engagement, which leads to higher quality operations. Lower operating costs pay for the upgrades—higher quality operations are a bonus. These actions can achieve other organizational goals while providing a positive financial return.
A Specific Example: Smart Irrigation
There are several major vendors of “smart” irrigation systems that can help reduce irrigation of corporate landscapes. The features of these systems range from rain monitors that turn off the watering timer when it’s raining (so that you don’t look dumb by watering in the rain) to systems that calculate the ideal irrigation schedule each day, based on the rain, temperature, and humidity. Each different type of system has its advantages, but to get the most effective use of water with the biggest use reduction, an “evapotranspiration controller” is probably your best bet.
Evapotranspiration controllers have a temperature sensor, a humidity sensor and a rain gauge. The controller might even connect to a local weather service over the internet. These inputs feed an algorithm which calculates a daily irrigation schedule. This system may eliminate irrigation use for days following a heavy rainfall.
Evapotranspiration controls for your irrigation system are relatively inexpensive (for a complex controller), though your system may need other changes to work efficiently with the controller, and you may need more than one controller for your property. Even so, the project payback in water fees saved is typically less than 9 months. In combination with changes to your landscaping to reduce the maintenance and water use, you have a very effective way to reduce operating expenses.
Where the Problems Are
There are several problems that building managers will need to overcome when trying to change landscape maintenance, irrigation, and pest control systems. The biggest problem is that each of these jobs is generally done by subcontractors who have no contact with your conservation goals. The landscape maintenance crew does not pay the water bills, nor do they typically have any idea how much water they use. The landscape planning team may understand how their designs affect stormwater run-off, but they do not experience it and they have no relationship with the municipality that manages the storm sewers. The pest control contractor is probably tuned in to local regulations more that the building management team, but has no contact with the surface water or other natural systems affected by their work.
One solution to these problems is to have a member of the building management team take responsibility for conservation and environmental impact at the property. This might seem to be one more added expense, but the savings from such attention will probably pay for the time. This also presents an opportunity to engage the building operations team, even a part-time team, in the quality of operations. This engagement can pay dividends for many years to come.
Resources for smart irrigation and low-impact pest control:
Rutgers University Low Impact Pesticides Website