Multi-Benefits of Onsite Non-potable Water Systems
When properly planned, design, constructed, and maintained these systems have numerous benefits over conventional “waste” and water treatment systems. Generally, onsite water reuse systems can:
- Save money
- Generate revenue
- Protect public health
- Preserve stream flows and fish habitat
- Promote resilience
- Save energy
Depending on your audience, you might find these talking points helpful:
- Free model codes and ordinances are available for under-resourced jurisdictions. Jurisdictions lack the capacity to implement new programs, so permitting language for nonpotable onsite systems based on a “risk-based framework” (RBF) is available for free download, adaptation if desired, and adoption. The RBF applies to rainwater, stormwater, greywater, and domestic sewage water sources. Source: Water Environment & Reuse Foundation
(Recode also has talking points on the Multi-Benefits of Adopting the Risk-Based Framework for Onsite Non-potable Water Systems.)
- Protect public health. Onsite nonpotable water systems can be permitted using an internationally accepted methodology that is more protective of public health than current EPA standards for conventional systems. Source: Water Environment & Reuse Foundation (WE&RF)
- Reduce resources used in the treatment process. Conventional water systems have a single quality of water, whether we’re drinking it or flushing our toilets. Instead of treating all water to a single potable (i.e. drinkable) standard, onsite waters can be treated to a level that considers their end use and disposal point (e.g. sewer draining to a municipal wastewater treatment plant, groundwater aquifer), which is also known as “fit for purpose” water.
- Address predicted water shortages with the next level of water conservation. Water reuse can reduce domestic water use by up to 60% when applied to nonpotable end uses such as irrigation and toilet flushing. This means that, similar to the recent past, as population increases, water shortages will not increase as quickly. Source: US Department of Energy
- Diversify a community’s water portfolio. Many places purchase or receive water from outside of their own jurisdiction. Water reuse systems provide an alternate water supply. Source: EPA
- Minimize flooding. Capturing rainwater and storing it in a tank for reuse can reduce flooding. Active rainwater harvesting systems have been found to be effective for optimizing runoff reduction and water supply. Source: EPA
- Protect sensitive waterways. Water reuse has been used as a means to reduce or eliminate municipal treatment plant discharges.
Enhance wetlands and groundwater supply. Reusing water more than once reduces pressure on groundwater supply needs, which are hydrologically connected to and influence wetlands. Source: EPA
- Reduce and prevent pollution. Water that will be reused is treated (or proposed to be treated) to a higher standard than current discharge standards.
- Reduce energy. At about 8 pounds per gallon, water is heavy. Anytime water must be pumped (which occurs in almost every system at some point) energy demands increase. Onsite water reduces the distance water must be pumped. Source: EPA
- Reduce algae blooms and other low flow impacts. Using water more than once leaves more water in the environment to reduce the frequency and impact of low flows. (Source: EPA) In addition, Trout Unlimited’s Coastal Streamflow Stewardship Project is a great case study for how rainwater harvesting can solve timing problems to reduce draws during low flow periods.
- Avoid large capitol improvement costs. Decentralized systems can be integrated into centralized system infrastructure to optimize opportunities to avoid large capital improvement costs. Source: EPA