Green Infrastructure benefits of harvest and use/re-use practices
Green infrastructure and multiple benefits
Green infrastructure (GI) encompasses a wide array of practices, including stormwater management. Green stormwater infrastructure (GSI) encompasses a variety of practices primarily designed for managing stormwater runoff but that provide additional benefits such as habitat or aesthetic value.
There is no universal definition of GI or GSI (link here for more information). Consequently, the terms are often interchanged, leading to confusion and misinterpretation. GSI practices are designed to function as stormwater practices first (e.g. flood control, treatment of runoff, volume control), but they can provide additional benefits. Though designed for stormwater function, GSI practices, where appropriate, should be designed to deliver multiple benefits (often termed "multiple stacked benefits". For more information on green infrastructure, ecosystem services, and sustainability, link to Multiple benefits of green infrastructure and role of green infrastructure in sustainability and ecosystem services.
Green Infrastructure benefits of harvest and reuse systems Water quality: Installation of harvest and reuse systems prevents or reduces a sites’ total pollution runoff amount Reduces downstream water treatment levels when water is stored on site Wastewater treatment requirements may be reduced due to the incorporation of reuse systems that use on site water for functions such as urinal flushing, water features, and sprinkler systems
Water quantity and hydrology Reduction in total water volume movement on the site through water retention techniques and retardation of peak flow from rainfall events at the site Harvest and reuse systems designed with storage containers are better able to withstand drought conditions than sites without them (Costs, Benefits, or Function? What Really Drives Water Reuse)
Energy Harvest and reuse systems provide indirect energy savings through reduced water treatment and distribution required by outside sources Harvest and reuse systems used to irrigate vegetation that provide shade, trees and plants, reduce air conditioning and heating costs (Using Trees and Vegetation to Reduce Heat Islands | US EPA)
Air quality Air quality impact is minimal, most benefits are indirect through vegetation grown by the harvest and reuse system
Climate resiliency Site water containment in harvest and reuse systems offers some reduction in flooding during rainfall events Plant vegetation grown with reuse irrigation systems provide carbon sequestration Reduction in pollutant runoff and wastewater treatment lowers total energy consumption and lowers the amount of chemicals needed to produce useable water for the site; this reduction in energy also lowers greenhouse gas requirements Reduction of the heat island effect when reuse systems are used to support a healthy on-site vegetation that provides shade (What You Can Do to Reduce Heat Islands | US EPA) Lower greenhouse gas emissions through reduced air conditioner use (Report Finds Onsite Water Reuse Can Boost Affordable Housing, Spread Climate Resilience – Texas Living Waters Project) The promotion of vegetation and biota growth, vegetative filtering, soil adsorption, and gravitational settling of pollutants that would otherwise be moved by rainfall events and create toxic blooms such as the algae blooms in the Gulf of Mexico
Habitat improvement Reduction of soil erosion from water runoff and increased soil stability promotes vegetation growth Less of a temperature impact to streams and rivers that receive water discharge and serve as fish and wildlife habitats
Community livability Harvest and reuse systems help to protect recreation sites for people by ensuring safe and healthy access to water sources and promotes on-site watering availability Water harvest and reuse are adaptable to meet needs such as community gardening, water fountain structures, promoting healthy green spaces, and may be used for recreation purposes if water quality requirements are met Water harvesting and reuse that promotes healthy landscaping can promote mental health improvements for those who frequent them (What are the physical and mental benefits of gardening? - MSU Extension) Larger reuse systems involved with irrigation practices involving trees and other shade proving vegetation reduce temperature levels (Reducing Urban Heat Islands: Compendium of Strategies: Trees and Vegetation (epa.gov))
Health benefits Reduction of downstream buildup of nutrients, pathogens, metals, TSS, and phosphorus among others as an indirect, off site benefit Increased longevity for fish and wildlife in the area through the reduction of compounds that wash into waterways as rain runoff Mental health improvements for the people who visit and live in areas that use reuse systems when reuse systems are used in conjunction with landscaping practices (What are the physical and mental benefits of gardening? - MSU Extension)
Economic benefits and savings Harvest and reuse systems can be expensive to install but they can reduce the total operating water cost for a building, site, or water features once they are implemented Well maintained harvest and reuse systems combined with vegetation can improve property aesthetics that increase property value Harvest and reuse systems provide a safeguard against drought conditions through stored water that can be used to keep landscaping alive and well over several days or weeks if necessary Potential for more affordable housing conditions when implemented as part of a renting strategy (Report Finds Onsite Water Reuse Can Boost Affordable Housing, Spread Climate Resilience – Texas Living Waters Project)