Ecosystem services from rainwater harvesting in India

Abstract

Availability of a safe and reliable water supply is an issue in developing nations, including India. Rainwater harvesting (RWH) is a site-specific source control used to satisfy human, agricultural, and safety demands for water. This study analyzed the effects of capturing rainwater for a 12.5 year period (Jan 1999 -Jun 2011) to provide three ecosystem services: water supplementation for indoor use, water supplementation for food production and groundwater recharge (GWR). A hydrologic analysis was completed using satellite rainfall data and a water balance approach. Two demand scenarios, indoor and outdoor, were considered, with water in excess of demand and storage directed to recharge groundwater. An economic analysis quantified RWH system net present value. The results indicated significant ecosystem services benefits were possible from RWH in India. RWH for the purpose of providing irrigation to a small garden and allowing overflow to a drywell for GWR was concluded to be an approach to maximize benefits. This scenario provided the greatest net present value (21,764-38,851 INR), fastest payback period (0.30 -0.98 years), and recharge to groundwater of more than 40% of onsite rainfall. The benefit of the outdoor vegetable irrigation was determined and the results showed that the caloric demands of the typical Indian household (2.75 kg of tomatoes and 1.05 kg of lettuce) could be met with a 20 m 2 garden, and excess food could be sold to offset the capital cost of the system and later for economic gain.

A Review of Rainwater Harvesting in Malaysia: Prospects and Challenges

“…RWHS can be defined as direct collection of rainwater from roof and other purpose-built catchments and the collection of sheet runoff from man-made ground or natural surface catchment and rock catchment for potable and non-potable uses. Studies on RWHS have been intensively carried out, since this system has several advantages for the environment and community [82][83][84][85][86][87][88][89][90][91]. Over the past four decades, the number of studies related to RWHS has increased exponentially as shown in Figure 3 based on a keyword 'RWHS' in Scopus database.…”

Using Rainwater Harvesting to Attain Sustainability Development Goals

“…Rain water harvesting systems can easily be popularized among people. Rain water harvesting system is found to be economically viable and it is one sector where the payback period is very small and net present value of the project is found to be attractive (Stout et al 2015).…”

“…Rainwater harvesting is a good solution that solves the water crisis of large metropolitans' cities like Mumbai, etc. The Mumbai City municipal council is now planning to make rainwater harvesting mandatory for all the large societies, through which they expect to improve the availability of water (Shankari and Shah 1993).…”

Urban Stormwater Characterization, Control, and Treatment

“…For modeling efforts to design rainwater systems, Campisano et al (2015) Devkota et al (2015) also used life cycle analysis for rainwater harvesting systems and found that energy and greenhouse gas emission payback periods were longer than the life of the building for all scenarios except rainwater for irrigation in a renovation project or rainwater for toilet flushing in a new project. Similarly, Stout et al (2015) determined that the best scenario to maximize ecosystem services benefits in India was using rainwater harvesting to irrigate a small garden, with the overflow going to a drywell for groundwater recharge. Finally, Malinowski et al (2015) estimated that in the US water utilities could save $270 million dollars annually in energy costs by replacing landscape irrigation and other outdoor water uses with rainwater harvesting.…”