A National Assessment of Water Availability and Use

摘要

Informed decisions about managing water resources start with a few basic questions. How much water flows down a river each year, each month, and right now? Is there groundwater at a site? How deep is it? Is it drinkable? How fast is itrnreplenished? Who are the other water users in the basin? When do they use the water? What happens to the water quality if new users are allowed? Will there still be fish, mussels, or crabs to eat? Communities across the United States-indeed,rnaround the world-face these simple questions every day. Answers to these questions are vitally needed as water resources become increasingly used and increasingly scarce.