Near-Continuous Depth-Dependent Water-Quality Data from Automatic Profiling Systems and Meteorological Data, Lakes Mead and Mohave, Arizona and Nevada, USA

Science Center Objects

The Colorado River is one of the most intensely used rivers in the western United States, providing recreational watercraft activities and domestic drinking, industrial, and irrigation water for over 22 million users in the desert southwest. The quality of this water must be maintained to guarantee a reliable and safe resource for its many uses. The Colorado River provides an estimated 97 percent of the inflow into Lake Mead. Lake Mohave is downstream of Lake Mead (separated by the Hoover Dam) and is part of the Lower Colorado River system.

Map of the Lake Mead National Recreation Area, Arizona-Nevada
Map of the Lake Mead National Recreation Area, Arizona-Nevada (modified from figure 1-1 in USGS Circular 1381).(Public domain.)

The USGS Nevada Water Science Center, in cooperation with its partners, collected near-continuous depth-dependent water-quality profile data from October 2000 through September 2016 at monitoring stations located throughout Lake Mead National Recreation Area (LAKE). In addition, hourly-averaged meteorological data were also collected from October 2004 through March 2017 at selected stations. The data were collected as part of a multi-agency monitoring network maintained to provide resource manag­ers with baseline water-quality data and to gain a better understanding of the hydrodynamics of the waters of LAKE.

Data Collection

The water-quality stations were as follows: Temple Basin near the Temple Bar Marina; Overton Arm Basin near the confluence of the Muddy and Virgin Rivers; Virgin Basin, near the Narrows, which separates the Virgin and Boulder Basins; Las Vegas Bay (Sites 1-4), near the confluence of the Las Vegas Wash; near Sentinel Island, Boulder Basin; Boulder Basin, approximately 2.5 miles upstream of Hoover Dam; and Lake Mohave, south southwest of the lake. Meteorological data were collected at the following stations: Temple Basin, Overton Arm Basin, Virgin Basin, Las Vegas Bay Site 4, Sentinel Island, and Boulder Basin.

Map of the water-quality platform sites on Lake Mead, Nevada-Arizona
Map of the water-quality platform sites on Lake Mead, Nevada-Arizona. (Public domain.)

The following water-quality data were collected using a multiparameter sonde as part of an automated profiling system:

  • depth,
  • water temperature,
  • specific conductivity,
  • pH,
  • dissolved oxygen, and
  • turbidity

In addition, the following meteorological data were collected:

  • air temperature,
  • relative humidity,
  • barometric pressure,
  • solar radiation, and
  • wind speed and direction

Quality-Assured Data

The following quality-assured water-quality data by profile and meteorological data that were not published in a USGS report are available here: