According to a new report released by The Nature Conservancy, investing in the water upstream from your city just might help secure water for urbanites. The project, titled Urban Water Blueprint, maps several city’s watersheds by combining hydrological models and data from the City Water Map, to convey where 534 large cities get their water from. The ultimate implication is that there is a more sustainable approach to engineer the water flow to our amenities and even save millions of dollars, as New York City has since adopting the Safe Drink Water Act in the nineties.

Despite the need to consistently provide clean drinking water to residents, cities often struggle to provide the capital that’s necessary for this service when they clean the water by the time it comes into the city’s boundaries. By investing in the “natural infrastructure,” or the riverbanks, forests and farmlands that the water originally comes from, the water systems address the pollution and sediments at the source rather than relying on additional treatment plans. According to the projects’ architects, this method is not only healthier, but it’s also more cost-effective.

Below are five cities listed by Next City that whose water systems have benefitted from low-tech and innovative solutions for water conservation and cleaning:

1. New York
2. San Diego
3. Santa Fe
4. Cape Town, South Africa
5. Manila, Phillipines

To see why each of these varying places made this list, go to the article at Next City. To learn more about investing in water sheds, go to The Nature Conservancy.