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T.G. Rowe

Publications and source records attributed to T.G. Rowe.

5 recordsLinked to original sources

Streamflow and water-quality data for selected watersheds in the Lake Tahoe basin, California and Nevada, through September 1998

The U.S. Geological Survey, in cooperation with the Tahoe Regional Planning Agency, and the University of California, Davis-Tahoe Research Group, has monitored tributaries in the Lake Tahoe Basin since 1988. This monitoring has characterized streamflow and has determined concentrations of nutrients and suspended sediment, which may have contributed to loss of clarity in Lake Tahoe. The Lake Tahoe Interagency Monitoring Program was developed to collect water-quality data in the basin. In 1998, the tributary-monitoring program included 41 water-quality stations in 14 of the 63 watersheds totaling half the area tributary to Lake Tahoe. The monitored watershed areas range from 1.08 square miles for First Creek to 56.5 square miles for the Upper Truckee River.Annual and unit runoff for 20 primary and secondary streamflow gaging stations in 10 selected watersheds are described. Water years 1988-98 were used to compare runoff data. The Upper Truckee River at South Lake Tahoe, Calif., had the highest annual runoff and Logan House Creek near Glenbrook, Nev., had the lowest. Blackwood Creek near Tahoe City, Calif., had the highest unit runoff and Logan House Creek had the lowest. The highest instantaneous peak flow was recorded at Upper Truckee River at South Lake Tahoe during the January 2, 1997, flood event.Certain water-quality measurements were made in the field. Ranges and median values of those measurements are described for 41 stations. Water temperature ranged from 0 to 23?C. Specific conductance ranged from 13 to 900 microsiemens per centimeter at 25?C. pH ranged from 6.7 to 10.6. Dissolved-oxygen concentrations ranged from 5.2 to 12.6 mg/L and from 70 to 157 percent of saturation.Loads, yields, and trends of nutrients and suspended sediment during water years 1988-98 at the streamflow gaging stations also are described. The Upper Truckee River at South Lake Tahoe had the largest median monthly load for five of the six measured nutrients and of suspended sediment, while Trout Creek at South Lake Tahoe had the largest median monthly load for the remaining nutrient. Logan House Creek near Glenbrook had the smallest median monthly loads for all nutrients and suspended sediment. Seasonal load summaries at selected stations showed nutrient and suspended-sediment loads were greatest in the spring months of April, May and June and least in the summer months of July, August, and September. Monthly load comparisons also were described for five watersheds with multiple stations.Incline Creek had the highest combined rank for all nutrients and sediment. Incline Creek had the largest monthly yields for dissolved nitrite plus nitrate nitrogen and soluble reactive phosphorus. Third Creek had the second highest combined rank and had the largest monthly yields for total nitrogen, total phosphorus, biologically reactive iron, and suspended sediment. Edgewood Creek had the largest monthly yield for dissolved ammonia nitrogen. Logan House Creek had the lowest combined rank and the smallest monthly yields for all nutrients and sediment.Trends in concentrations are either decreasing or not significant for all nutrients in all sampled watersheds, with the exception of biologically reactive iron. Biologically reactive iron and suspended sediment show an increasing trend in three watersheds and decreasing or no significant trend in the other seven watersheds.

Water-Resources Investigations Report

Surface- and ground-water characteristics in the Upper Truckee River and Trout Creek watersheds, South Lake Tahoe, California and Nevada, July-December 1996

The Upper Truckee River and Trout Creek watersheds, South Lake Tahoe, California and Nevada, were studied from July to December 1996 to develop a better understanding of the relation between surface water and ground water. Base flows at 63 streamflow sites were measured in late September 1996 in the Upper Truckee River and Trout Creek watersheds. Most reaches of the main stem of the Upper Truckee River and Trout Creek had gaining or steady flows, with one losing reach in the mid-section of each stream. Twenty-seven of the streamflow sites measured in the Upper Truckee River watershed were on 14 tributaries to the main stem of the Upper Truckee River. Sixteen of the 40 streamflow sites measured in the Upper Truckee River watershed had no measurable flow. Streamflow in Upper Truckee River watershed ranged from 0 to 11.6 cubic feet per second (ft3/s). The discharge into Lake Tahoe from the Upper Truckee River was 11.6 ft3/s, of which, 40 percent of the flow was from ground-water discharge into the main stem, 40 percent was from tributary inflows, and the remaining 20 percent was the beginning flow. Gains from or losses to ground water along streams ranged from a 1.4 cubic feet per second per mile (ft3/s/mi) gain to a 0.5 ft3/s/mi loss along the main stem. Fourteen of the streamflow sites measured in the Trout Creek watershed were on eight tributaries to the main stem of Trout Creek. Of the 23 streamflow sites measured in the Trout Creek watershed, only one site had no flow. Flows in the Trout Creek watershed ranged from zero to 23.0 ft3/s. Discharge into Lake Tahoe from Trout Creek was 23.0 ft3/s, of which, about 5 percent of the flow was from ground-water discharge into the main stem, 75 percent was from tributary inflows, and the remaining 20 percent was the beginning flow. Ground-water seepage rates ranged from a 1.4 ft3/s/mi gain to a 0.9 ft3/s/mi loss along the main stem. Specific conductances measured during the seepage run in September 1996 increased in a downstream direction in the main stem of the Upper Truckee River and remained relatively constant in the main stem of Trout Creek. Water temperatures measured during the seepage run also increased in a downstream direction in both watersheds. Depths to ground water measured at 62 wells in the study area were used with the results of the seepage run to produce a water-level map in the Upper Truckee River and Trout Creek watersheds. Ground-water levels ranged from 1.3 to 69.8 feet below land surface. In the upper sections of the watersheds ground-water flow is generally toward the main stems of Upper Truckee River and Trout Creek, whereas in the lower sections, ground-water flow generally parallels the two streams and flows toward Lake Tahoe. The altitude of ground water between Lake Tahoe and Highway 50 was nearly the same as the lake-surface altitude from July to November 1996. This suggests ground-water discharge beneath the Upper Truckee River and Trout Creek drainages directly to Lake Tahoe was minimal and that much of the ground-water discharge was to the channels of the Upper Truckee River and Trout Creek upstream from Highway 50. Hydraulic gradients ranged from near zero to 1,400 feet per mile. Samples were collected at six surface-water-quality and eight ground-water-quality sites from July through mid-December 1996. Specific conductance of the ground-water-quality sites was higher than that of the surface-water-quality sites. Water temperature and pH median values were similar between ground-water-quality and surface-water-quality sites but ground water had greater variation in pH and surface water had greater variation in water temperature. Ground-water nutrient concentrations were generally higher than those in streams except for bioreactive iron.

Water-Resources Investigations Report

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in and near Stillwater Wildlife Management Area, Churchill County, Nevada, 1986-87

A reconnaissance was initiated in 1986 to determine whether the quality of irrigation-drainage water in and near the Stillwater Wildlife Management Area, Nevada, has caused or has potential to cause harmful effects on human health, fish, wildlife, or other beneficial uses of water. Samples of surface and groundwater, bottom sediment, and biota were collected from sites upstream and downstream from the Fallon agricultural area in the Carson Desert, and analyzed for potentially toxic trace elements. Other analysis included radioactive substances, major dissolved constituents, and nutrients in water, and pesticide residues in bottom sediment and biota. In areas affected by irrigation drainage, the following constituents were found to commonly exceed baseline concentrations or recommended criteria for protection of aquatic life or propagation of wildlife: In water, arsenic, boron, dissolved solids, molybdenum, sodium, and un-ionized ammonia; in bottom sediments, arsenic, lithium, mercury, molybdenum, and selenium; and in biota, arsenic, boron, chromium, copper, mercury, selenium, and zinc. In some wetlands, selenium and mercury appeared to be biomagnified, and arsenic bioaccumulated. Pesticides contamination in bottom sediments and biota was insignificant. Adverse biological effects observed during this reconnaissance included gradual vegetative changes and species loss, fish die-offs, waterfowl disease epidemics, and persistent and unexplained deaths of migratory birds. (USGS)

Water-Resources Investigations Report