Fountain scheduling strategies for improving water-use efficiency of artificial ice reservoirs (Ice stupas)

Abstract

Artificial ice reservoirs (AIRs), also called ice stupas, are a climate-change adaptation strategy developed in the Indian Himalayas (Ladakh). With this technology, otherwise unused stream/spring water is stored in large ice towers during the winter. The surplus melt water generated in spring is used to satisfy irrigation water demands. Recent studies have shown that, during AIR construction, over 75% of the water sprayed is lost. In order to reduce these water losses, different fountain scheduling strategies implemented on two AIRs under identical weather conditions were compared. In one scheduling strategy, the fountain was operated manually (non-scheduled fountain) whereas in another it was operated via an automation system (scheduled fountain). The automation system computed recommended discharge rates using real-time meterological input and location metadata. Scheduled fountains produced similar ice volume while consuming one-tenth of the water the non-scheduled fountain used. Simulations converting non-scheduled fountains into scheduled fountains showed a threefold improvement in water-use efficiency. Overall, these results show that automated fountain water supply management can increase water-use efficiency of AIRs and reduce their maintenance without compromising their meltwater production.