This ancient water practice could help with Peru's drought

Amunas being built by the group Aquafondo in the Andes. Source: Noticias Telemundo

The future of water access in Peru might be in engineering practices from 1,400 years ago.

Why it matters: Andean nations like Peru have experienced prolonged droughts in the past few years. Chile announced a water rationing plan this April.

• Those countries partly depend on mountain snowmelt for their freshwater supply.
• But increasing temperatures due to human-caused climate change has accelerated snowmelt and the melting of mountain glaciers. This has reduced glacial water reserves overall, and caused the higher volume of water that comes down to pick up sediments, which muddies rivers.

Driving the news: The non-governmental organization Aquafondo just launched a project to build or recover 20 miles of canals known as amunas in Peru.

• Amunas collect water from rivers, gullies and rain during high season and move it to areas with rocky subsoil.
• Some amunas, also called mamanteos, already feed into parks and green areas in Lima, the nation's capital and world’s second largest desert city, but the project could help provide more water.

How it works: Amunas divert water to rocky areas so it moves downhill more slowly.

• By the time the dry season starts in April, the water has reached springs and aquifer reservoirs called ojos de agua.
• The Amunas method, developed by the pre-Inca Wari peoples, is nicknamed “planting water.”

What's next: Aquafondo, which is using public and private financing for its project, says it can supply over 1.8 million gallons of water, enough for to meet the yearlong water needs of 20,000 people (about 26 daily gallons, per the World Health Organization.)

• Developing more amunas could increase water volume in the dry season by 7.5% each year, according to a study by the Natural Infrastructure for Water Security Project. The study didn't specify how many more miles were needed.