Elevation-Area-Capacity Relationships of Lake Powell in 2018 and Estimated Loss of Storage Capacity Since 1963

Scientific Investigations Report 2022-5017
Water Resources Mission Area
Prepared in cooperation with the Bureau of Reclamation
By:  and 



Lake Powell is the second largest constructed water reservoir by storage capacity in the United States and represents a critical component in management of water resources in the Colorado River Basin. The reservoir provides hydroelectric power generation at Glen Canyon Dam, banks water storage for the Upper Colorado River Basin, stabilizes water commitments downstream, and buffers the Lower Colorado River Basin, including Lake Mead, against sedimentation and fluctuations in hydrological conditions. With completion of the dam in 1963, Lake Powell steadily filled with water before reaching full pool in 1980 and has become a popular destination for recreation, welcoming more than 4 million visitors per year. Since the early 2000s, severe drought and increases in water demand have resulted in a significant drop in reservoir elevation and stored water, prompting a heightened level of interest in the current state and future of Lake Powell.

Beginning in 2017, the U.S. Geological Survey, in cooperation with the Bureau of Reclamation, completed topobathymetric surveys of Lake Powell for the first update of elevation-area-capacity relationships since 1986. This report presents results of these surveys and comparisons with estimates from previous surveys. The storage volume and surface area, as of completion of the topobathymetric survey in spring 2018, are calculated at 0.33-foot (0.10-meter) increments for elevations ranging from 3,120.08 to 3,717.19 feet above the North American Vertical Datum of 1988 (NAVD 88). Between 0.33-foot increments, the storage volumes and areas were linearly interpolated at 0.01-foot intervals. Interpolation error in the 0.01-foot interval estimates was assessed at lower (3,160.00–3,161.00 feet above NAVD 88), middle (3,400.00–3,401.00 feet above NAVD 88), and upper (3,700.00–3,711.00 feet above NAVD 88) elevations. The interpolated storage capacity and area estimates are comparable to the measured values with differences ranging from 0.00 to 0.02 percent and from −0.01 to 0.03 percent, respectively.

Current storage capacity at full pool (3702.91 feet above NAVD 88) is 25,160,000 acre-feet. Compared to previously published estimates, this volume represents a 6.79 percent or 1,833,000-acre-foot decrease in storage capacity from 1963 to 2018 and a 4.00 percent or 1,049,000-acre-foot decrease from 1986 to 2018. Areal extent, as of spring 2018, at full pool is 159,200 acres, which represents a 1.33-percent decrease from 1963 to 2018 and a 0.96 percent decrease from 1986 to 2018.

Suggested Citation

Root, J.C., and Jones, D.K., 2022, Elevation-area-capacity relationships of Lake Powell in 2018 and estimated loss of storage capacity since 1963: U.S. Geological Survey Scientific Investigations Report 2022–5017, 21 p., https://doi.org/10.3133/sir20225017.

ISSN: 2328-0328 (online)

Study Area

Table of Contents

  • Acknowledgments 
  • Abstract 
  • Introduction 
  • Methods 
  • Results 
  • Discussion on Rates of Storage Loss 
  • Summary 
  • References Cited 
  • Glossary 
Publication type Report
Publication Subtype USGS Numbered Series
Title Elevation-area-capacity relationships of Lake Powell in 2018 and estimated loss of storage capacity since 1963
Series title Scientific Investigations Report
Series number 2022-5017
DOI 10.3133/sir20225017
Year Published 2022
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Utah Water Science Center
Description Report: vii, 21 p.; 2 data releases
Country United States
State Arizona, Utah
Other Geospatial Colorado River, Glen Canyon Dam, Glen Canyon National Recreation Area, Lake Powell
Online Only (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details