
It is difficult to imagine modern economies functioning without a ready supply of fresh water. Rivers are the single largest supplier of this resource to humans. Without clean, reliable rivers, economic development will remain but a dim hope for billions. In addition, rivers – along with lakes and wetlands – maintain critical amounts of the earth’s biodiversity, providing a collective, global ecosystem for over 120,000 animal species (around 10% of all animal species known), including a one third of all vertebrates.
Despite their importance, rivers the world over are distorted, dried, and clogged with the byproducts from a planet crowded with humans, our croplands, and our factories. Decades of neglect render much of the planet's water supply highly threatened. Like politics, water problems are all local – they have often been viewed as unique or confined to our own backyard. But new data sources and mapping techniques are uncovering water syndromes and rivers in crisis on a global scale. Issues as diverse as toxic pollution, poor land management, invasive species, overfishing, and overuse of irrigation water conspire to produce a sobering reality: two-thirds of all rivers are highly degraded, along with the freshwater habitat they support. Freshwater biodiversity is more threatened than in any other ecosystem on the planet.

As rich countries secure clean water for their population’s use at the expense of biodiversity, the world's poor are left in a dire state. Exposure to unsafe drinking water and poor sanitation already result in two million preventable deaths a year from diarrhea. By pursuing developed world models of water resource development, most poor countries will be unable to afford the costly engineering investments that offset the water supply threats. These countries will be locked in a vicious cycle of capital and energy intensive engineering solutions, progressive water degradation and overuse, and ever-expanding reliance on costly remedies.
We can turn to nature – and to protecting biodiversity – for an answer. Natural watersheds have a remarkable capacity to buffer against floods and droughts, support productive fisheries, and purify water. Just as preventive medicine proves more cost-effective than intensive care, strategic water policy must be refocused on avoiding problems before they arise. The City of New York has demonstrated such cost-effectiveness in its effort to protect the watersheds that feed the public water supply. Although such integrated approaches are not yet widely applied, they are taking hold, like in successful programs in South America instituted by the Nature Conservancy. In a further sign that integrated approaches are gaining traction, the Secretariat of the Convention on Biodiversity recently published an instructive booklet, “ Natural Solutions for Water Security.” We would do well to promote such alternative approaches aimed at ensuring water security for all, as water takes a prominent place during this year’s International Day for Biodiversity.
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