Editing Columbia Basin Project (section)

==Irrigation==
When it was built, Grand Coulee Dam was the largest dam in the world, but it was only part of the irrigation project. Additional dams were built at the north and south ends of Grand Coulee, the dry canyon south of Grand Coulee Dam, allowing the coulee to be filled with water pumped up from the Columbia River. The resulting reservoir, called [[Banks Lake]], is about {{convert|30|mi|km}} long. Banks Lake serves as the CBP's initial storage reservoir. Additional canals, [[siphon]]s, and reservoirs were built south of Bank Lake, reaching over {{convert|100|mi|km}}. Water is lifted {{convert|280|ft|m}} from Lake Roosevelt to feed the massive network.

The total amount of the Columbia flow that is diverted into the CBP at Grand Coulee varies a little from year to year, and is currently about 3.0 million acre-feet. This is about 3.8 percent of the Columbia's average flow as measured at the Grand Coulee dam.<ref>{{Cite web|url=http://www.ijc.org/php/publications/html/columbia/columbia_cy01.htm|title=Columbia River - Annual Report 2001|website=www.ijc.org|access-date=2018-03-16|archive-url=https://web.archive.org/web/20171223000035/http://www.ijc.org/php/publications/html/columbia/columbia_cy01.htm|archive-date=2017-12-23|url-status=dead}}</ref>  This amount is larger than the combined annual flows of the nearby Yakima,<ref>https://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure60.pdf {{Bare URL PDF|date=March 2022}}</ref> Wenatchee,<ref>https://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure56.pdf {{Bare URL PDF|date=March 2022}}</ref> and Okanogan<ref>https://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure52.pdf {{Bare URL PDF|date=March 2022}}</ref> rivers. There were plans to double the area of irrigated land, according to tour guides at the dam, over the next several decades. However, the Bureau of Reclamation website states that no further development is anticipated, with {{convert|671000|acre|km2}} irrigated out of the original {{convert|1100000|acre|km2}} planned.<ref>[http://www.usbr.gov/dataweb/html/columbia.html Bureau of Reclamation website] {{webarchive |url=https://web.archive.org/web/20081206014532/http://www.usbr.gov/dataweb/html/columbia.html |date=December 6, 2008 }}</ref>

Interest in completing the Columbia Basin Project's {{convert|1100000|acre|km2}} has grown in the late 20th and early 21st centuries. One reason for the renewed interest is the substantial depletion of the [[Odessa aquifer]]. Agricultural operations within the CBP's boundaries but outside the developed portion have for decades used groundwater pumped from the Odessa aquifer to irrigate crops.<ref name=75years/>