The global development community is gearing up to adopt the Sustainable Development Goals (SDGs) in September, illustrating a key shift in development priorities. Rather than focusing purely on goals and indicators, as the MDGs did, this new set of goals will additionally focus on the sustainability of development. One huge task is to provide global water security. Amidst rapid urbanization, water security in cities is a growing struggle, and providing water sustainably is even more of a challenge. A possible solution to this lies in “green infrastructure.”
“Green infrastructure” refers to a type of infrastructure engineered to maximize natural processes to manage water, mainly for cities and urban areas. These natural processes can include filtration through certain soils, flows of water through aqueducts and other gravity-based processes, or storing run-off water in certain specified land areas. These “green” processes can help control polluted run-off and erosion, as well as helping to sustainably and continually provide clean water for cities. Green infrastructure is distinguished from “gray infrastructure,” which includes the more typical basins, sewage systems, pipes, and filtration centers. Gray infrastructure can be expensive, cumbersome, and often subject to degradation over time. In many cases “green infrastructure” offers a sustainable way to manage, store, and distribute water because it utilizes natural processes instead of imposing artificial systems.
Lima, Peru is revitalizing a pre-Incan canal system for more effective and sustainable water management and treatment.
One example of green infrastructure was recently in the news for its innovative approach to providing water to Peru’s desert capital city, Lima. In response to a growing water shortage, Lima has dedicated $22 million to restore an ancient, pre-Incan canal system. The canals funnel water from mountain streams into the mountain itself, where it percolates, filtrates, and releases slowly over the course of the dry season. “Gray infrastructure” water management techniques would send the water too quickly to Lima, which would result in mudslides and erosion in the wet season and severe water shortages in the dry season. The green infrastructure solution adds at least 1 cubic meter per second of water to the city. This solution is also cheaper than building a canal or storage facilities, especially in light of the rapid urbanization of the region. Lima is expected to grow by at least 700,000 people in the next five years, and green infrastructure solutions are flexible and sustainable even with that growth. Continue reading →