Roof Top Rainwater Harvesting for Recharging Ground Water Technology

Over exploitation for drinking and irrigations together with drought due to climate change has caused depletion of ground water resources in Terai. Rajkumar Das, Executive Officer of Golbazar Municipality said, “Until few years back people could pump out drinking water from 40ft- 45ft below the ground but now it needs penetration of up to 150ft - 160 ft”. Local communities especially women are negatively impacted due to depletion of water as they are primarily responsible for managing water for household chores.

Roof Top Rainwater Harvesting and Recharging Ground Water Technology was an option to be tested to replenish the ground water in Terai. Accordingly, Rajbiraj Municipality Executive Officer Mr. Bishnu Gurung piloted Roof Top Rainwater Harvesting and Recharging Ground Water Technology for recharging ground water in Rajbiraj Municipality premises in 2015. In this connection he constructed recharge pits together with water harvesting tank and made arrangement to pipe water in these pits and tanks from office building roofs through financial support of Environment Friendly Local Governance Program (EFLGP) that is implemented under Local Governance and Community Development Program of the Ministry of Federal Affairs and Local Development (MoFALD).

According to Mr. Gurung the project has yielded multitudes of benefits this year. Water at the office premises has been recharged that can be exemplified from the fact that greenery around the pits has been maintained even in the dry season of 2016. Municipality Office adjoining settlements are enjoying drinking water benefits from the project as they have been able to pump water by digging only 30ft.-35 ft ground which not the case was before. Moreover, a tank having capacity of 15 m³ was with full of water has been maintained nearby by the recharge pit that can be utilized to fight fire in the Municipality if and when needed. Moreover, excess recharged water could be a sustainable source for maintaining Bhagwati Pond that is placed some 20 meter north from the recharge pit.  However, robustness and sustainability of the technology linking it with climate change impact needs further study in the days ahead.  

In summary, Roof Top Rainwater Harvesting and Recharging Ground Water Technology could be an option to deal with the issue of ground water depletion due to over utilization and climate change in Terai. In this regard Roof Top Rainwater Harvesting and Recharging Ground Water Technology has been piloted in Rajbiraj Municipality. The technology has yielded positive results against its intended objectives. However, sustainability and robustness of the technology as such needs further study.

The case was prepared by Ek Raj Sigdel based on field observation and interaction with Municipality Official in Saptari District in April 2016.