Skip to main content
U.S. flag

An official website of the United States government

Inter‐basin transfers extend the benefits of water from forests to population centers across the conterminous U.S.

Author(s):

G. Rebecca Dobbs
Stacy A. C. Nelson
Paul V Bolstad

Year:

2022

Publication type:

Scientific Journal (JRNL)

Primary Station(s):

Southern Research Station

Source:

Water Resources Research. 58:

Description

Clean water from forests is commonly used to supply drinking water to communities both within and outside basin boundaries through inter-basin transfers (IBTs). Here, we modified the Water Supply Stress Index (WaSSI) model to provide estimates of mean water yield and the proportion of mean flow originating on forested lands at the 12-Digit Hydrologic Unit Code scale across the conterminous United States (CONUS). We accounted for the benefits of forests for drinking water supply and receiving populations through IBTs by incorporating a new IBT database, surface intake location information for public drinking water systems, and modeled water yield from forests. We compiled the new database of 594 IBTs ranging from 0.01 million m 3 yr -1 to 8,900 million m 3 yr -1, for a total transferred volume of 116,894 million m 3 yr -1. According to our results, forested lands comprised 28.7% of the total land area across CONUS, but contributed 46% of the total surface water yield. Approximately 125.5 million people derived more than 10% of their surface drinking water supply from forested lands, and 83.1 million people received more than 50% of their surface drinking water supply from forested lands. Of those 83.1 million people receiving more than 50% of their surface drinking water supply from forested lands, 19.4 million people obtained some (≥0.01%) of that water through IBTs. We conclude that accounting for IBTs is critical to accurately assess the contribution of forested watersheds for surface drinking water supply. Hydrologic models for assessment and decision making must include IBTs to fully account for the effects of climate change and human population dynamics on water resource availability at watershed to regional scales. Results from this study can aid water resource and forest managers in developing integrated watershed management plans at a time when climate change, population growth, and land use change threaten water supplies.

Citation

Liu, Ning; Dobbs, Rebecca; Caldwell, Peter V.; Miniat, Chelcy Ford; Sun, Ge; Duan, Kai; Nelson, Stacy A. C.; Bolstad, Paul V.; Carlson, Christopher P. 2022. Inter-basin transfers extend the benefits of water from forests to population centers across the conterminous U.S. Water Resources Research. 58: e2021WR031537.

Cited

Publication Notes

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
https://www.fs.usda.gov/treesearch/pubs/64305