Satellite remote sensing has transformed environmental law enforcers into clairvoyants thanks to an app on drinking water sources developed by the Ministry of Ecology and Environment, People's Daily reported.

Law enforcement on drinking water source protection zones is difficult due to its unique characteristics - some drinking water source protection zones are as large as thousands of square kilometers while some are located in remote mountainous areas which are hard to access. Therefore, traditional ground investigation to locate violators is high in cost and workload and low in timeliness.

The drinking water source enforcement app integrates satellite remote sensing images, water environment problems spotted by satellite, water protection zone boundary's spatial data, water environment problems found by provinces and cities themselves and law enforcement data at the scene, and sends environmental problem lists to law enforcers at the scene to guide their work.

The app was used during the nationwide inspection on water sources in 2018 and the law enforcement during water sources inspection at county level this year.

Meng Zhiqi, a law enforcer with the water ecology and environment department of Shanghai bureau of ecology and environment, has witnessed the app's ability. "We received a message from a work team of the Ministry of Ecology and Environment, saying there was an illegal shrimp farming house with a chimney deep inside a water resource conservation forest, but my colleagues and I didn't know how to get there. Later, we followed the map provided by the app and demolished the house within 24 hours," said Meng.

The remote sensing can also be used in making electric and visual files for water source protection zones after matching the satellite remote sensing images and the ground situation. Such work has been trialed in four cities. In the future, satellite remote sensing will become a normal method in everyday law enforcement of water sources and long-term supervise.

"The innovation of using satellite remote sensing in water protection has made water source protection precise and intelligent. The management of water source no longer totally depends on manpower," said Yao Yanjuan, expert of satellite center with the Ministry of Ecology and Environment.