How to Reduce Outdoor Water Consumption when Landscaping for Green Buildings
Water is a limited and expensive resource. Outdoor water use accounts for most of our available water consumption. Therefore, for environmental and financial benefits it is necessary to reduce its use. We will review two strategies to reduce water consumption and ensure that building performance is optimized to be more sustainable and possibly gain green building certification points.
Xeriscaping - designing landscapes to reduce irrigation
This ‘green building strategy’ is most often implemented by replacing cliche ‘grassy lawns’ with soil, rocks, mulch, and native plant species that mimic a more natural environment. Native plants, that are suited to the climate, require almost no extra water than what is provided through the annual rainfall patterns; It is therefore much easier and cost efficient to sustain these landscapes. The higher water conservation and lower maintenance are not the only benefits of xeriscaping, planting or preserving native plants found on site improve the local biodiversity by recreating or maintaining existing habitats of local species.
A xeriscaped yard in Niwot designed by J&S Landscape. Photo courtesy of J&S Landscape.
Drip Irrigation- an optimized alternative
Another reliable strategy to save water wastage is through the adoption of drip irrigation systems. This irrigation system distributes water drop by drop, as needed by plants, thus ensuring the water gets absorbed by the plants before it has time to evaporate. This method also distributes water in proximity to the roots of a plant, where it is the most needed and efficiently placed to be absorbed.
A well designed, installed, and managed, drip irrigation is more efficient than other irrigation systems such as sprinkler or surface irrigation. Despite often having a higher initial installation cost, the overall maintenance and usage of drip irrigation systems is much lower over the lifetime due to reduced water and energy costs and the high efficiency of the system. Drip irrigation systems are more versatile since they can irrigate irregular shaped landscapes and accommodate a wider range of soil types, which may be a limitation with other irrigation systems.
Drip irrigation representation,
According to the USGBC, buildings can earn up to 2 LEED points in the ‘Water Efficiency’ category for ‘Outdoor Water Use Reduction’. The credit is intended “to reduce outdoor potable water consumption and preserve no and low-cost potable water resources”.
To learn more about the LEED credits available for Outdoor Water Use Reduction visit https://www.usgbc.org/credits/new-construction-core-and-shell-schools-new-construction-retail-new-construction-healthc-164 for more information.