With two out of every three people expected to be living in cities within the next three decades, it is important to take the steps today that will ensure sustainable, water-efficient urban landscapes for generations to come. Precision irrigation, in combination with smart landscape design, will make sure that the cities of the future have green spaces, cleaner air, and cooler temperatures.
Not Just a Pretty Face
According to a UN report, as of 2014 54% of the world’s population was living in urban areas (vs. 30% in 1950). By 2050, 66% of the world population is expected to be urban. It is critical, therefore, that cities strive to become healthier and more sustainable living environments, and there is growing awareness that urban vegetation has a substantive role to play, beyond its aesthetic value.
Urban landscaping, for example, reduces the “heat island effect” – a warming effect in built-up areas that, on average, raises the temperature by 1.8-5.4°F (~1-3°C). During peak summer heat, urban vegetation can reduce air temperatures by 2-9°F (~1.1-5°C), reducing the energy consumed for cooling by as much as 25%. [1]
Urban vegetation also [1]:
Removes harmful air pollutants and reduces carbon dioxide in the atmosphere.
Reduces soil erosion caused by storm water runoff – a problem intensified by the large expanses of impervious surfaces in the urban environment.
Filters out pollutants from storm water runoff, preventing contaminated water from entering natural fresh water sources, such as rivers.
Water-Efficient Urban Landscaping
Despite its significant role in the quality of urban life, urban landscaping is sometimes attacked as a water-waster in a world that is becoming increasingly aware of the need to carefully steward fresh water resources. In the US, the area of irrigated lawns is three times greater than the area of irrigated corn [2], and the water used for landscaping constitutes 65-75% of urban water usage. [3]
Successful water conservation in urban landscaping requires long-term education and policy changes that can change the behavior of large numbers of people, without sacrificing expectations for aesthetically pleasing green spaces. [4] Originally developed for drought-stricken and other arid regions, xeriscaping, for example, promotes landscaping practices that eliminate or dramatically reduce the need for additional irrigation. Xeriscaping best practices, which have been embraced by forward-looking cities even in non-arid regions, include the use of native plants that can thrive without irrigation, landscape contouring to maximize the irrigation effect of natural precipitation, mulching and other techniques to reduce evapotranspiration, and the usage of alternative sources of irrigation water, such as gray water or treated waste water. [2]
The Role of Precision Irrigation
One of the greatest long-term contributors to water-efficient urban landscaping is precision irrigation. Today smart water management systems, such as Mottech’s ICC IRRInet solution, are being embraced by municipalities to optimize the irrigation of turf and other landscaped areas.
Precision irrigation uses soil sensors and other inputs, such as weather conditions, to schedule irrigation sessions according to the measured need to replace soil water lost to evapotranspiration. [4] In addition, user-friendly irrigation command and control systems make it easy to program irrigation in the early hours or evenings only, avoiding inefficient mid-day sessions. [5]
Other precision irrigation best practices include:
Wherever possible, switch to drip irrigation vs. sprinklers.
Set up irrigation zones, to optimize irrigation patterns to specific soil conditions and plant needs.
Quickly detect and fix water leakages, including replacing faulty valves.
Final Note
With two out of every three people expected to be living in cities within the next three decades, it is important to take the steps today that will ensure sustainable, water-efficient urban landscapes for generations to come. Precision irrigation, in combination with smart landscape design, will make sure that the cities of the future have green spaces, cleaner air, and cooler temperatures.
