English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

An appraisal of surface-water quality in the Umpqua River basin was made using existing monthly data collected by the Oregon Department of Environmental Quality and the U.S. Geological Survey in cooperation with the Douglas County Water Resources Survey. This appraisal was limited to interpretation of instantaneous monthly water-quality data collected in the Umpqua River basin from water years 1974 to 1983. /These data were used to compare water-quality conditions throughout the basin and to determine if data collected from the NASQAN (National Stream Quality Accounting Network) station are representative of upstream basin conditions. In general, data collected at the NASQAN station represent a composite of water quality from the North and South Umpqua Rivers. These river basins account for 82 percent of the NASQAN station drainage. During the winter months, discharge and related water-quality conditions at the NASQAN station represent a uniform composite of both rivers, because 40 to 50 percent of the discharge is from the North Umpqua River and 40 to 50 percent from the South Umpqua River. During summer low flows only about 10 percent of the discharge at the NASQAN station is from the South Umpqua River; consequently, discharge and related water-quality conditions at the NASQAN station do not equally represent those conditions observed in the South Umpqua River. Water-quality concentrations, loads, yields, and trends were statistically described and related to point-source effluent loads and basin characteristics including hydrogeology, hydrology, population, land use, and water use. Available pointand nonpoint-source data provided minimal information for determining cause-effect relations and for explaining observed trends in water quality; however, the data did indicate that the largest effluent discharges are located in the South Umpqua River basin in the Roseburg-Winston area. Instantaneous and annual flow-weighted levels of specific conductance, phosphorus, organic plus ammonia nitrogen, nitrite plus nitrate, and fecal coliform bacteria are generally highest in the South Umpqua River near Roseburg. These high levels generally occur during the summer months when river flow is extremely low relative to flow in the North Umpqua River. The North Umpqua River has among the lowest constituent concentrations observed in the basin; with its higher summertime base flows, the North Umpqua River mixes with the South Umpqua River at river mile 111.7 and dilutes constituent concentrations in the main stem so that concentrations at the NASQAN station are between those observed in the North and South Umpqua Rivers. Constituent loads and yields for 1977 WY were computed for nine stations using constituent transport curves; based on load versus discharge regressions. Annual loads are reported only for 1977 water year (a lower than normal flow year), because this was the only year during the data-collection period when dai'.y loads could be computed without extrapolations of the loadversus discharge-regression equations. Even though annual loads for 1977 WY are not typical of loads in a normal flow year, they could be[used to provide insight to point-source loads and the quality of ground-water contributions. INTRODUCTION Purpose and Scope The U.S. Geological Survey is presently operating NASQAN (National Stream Quality Accounting Network) to define the distribution of the quantity and quality of surface water of the major rivers of the United States. The network consists of fixed-station water-quality sites located at or near the termini of large river basins. Data collected at a NASQAN station represent a composite of natural and man-caused conditions that occur at upstream reaches. These data provide national and regional managers with broad-scale information on the temporal and spatial variability of the quantity and quality of water leaving major river basins. However, these stations, ea$h located at a single downstream point in a basin, are generally inappropriate for identifying localized upstream problems. Instead, dat& from these stations probably represent an integration of water quality throughout a basin. The purpose of this report is to (1) describe the spatial and temporal variability of stream-water quality within the Umpqua River basin, upstream of the NASQAN station at Unpqua RM (river mile) 56.9 near Elkton, Oregon; (2) relate water quality to general causes, such as point-source discharges and selected basin characteristics, including land use and water use; (3) assess the adequacy of using water-quality data collected at the NASQAN station to represent water quality at upstream reaches; and (4) describe the minimum data-collection program necessary to represent water quality in the Umpqua River basin. CO Data previously collected by the Geolc Department of Environmental Quality) were this report, instantaneous monthly data from sites were examined. The water-quality from 1974 through 1983 WY (water year). data Description of Stud's gical Survey and DEQ (Oregon mpiled and compared. In 12 fixed-station monitoring were collected primarily Area The Umpqua River basin is located in southwestern Oregon and drains an area of approximately 4,560 square miles;. It is the eleventh largest basin in Oregon (Oregon State Water Resources Board, 1958). The basin boundary is nearly congruent with the boundary of Douglas County (fig. 1), extending from the Pacific Ocean to the Cascade Range. E X P L A N A T IO N RM 4 8. 6 A S am pl in g si te ( S ite l oc at io n an d st at io n na m e lis te d be lo w .) U m pq ua R M 4 B .6 a t E lk to n , O re g. , B rid ge ( D E Q ) U m pq ua R M 5 6. 9 ne ar E lk to n , O re g. ,( 14 32 10 00 ; N A S Q A N ; U S G S ) U m pq ua R M 7 1. O at K el lo gg , O re g. , B rid ge ( D E Q ) U m pq ua R M 1 02 .7 a t U m pq ua , O re g. , B rid ge ( D E Q ) C al ap oo ya C re ek n ea r m o u th a t U m pq ua , O re g. ( D E Q ) N o rt h U m pq ua R iv er a t B ro w n' s B rid ge n ea r m o u th ( D E Q ) S ou th U m pq ua R M 1 17 .7 a t M el ro se R oa d ne ar R os eb ur g, O re g. (1 4 3 1 2 2 6 0 ; U S G S ; D E Q ) S ou th U m pq ua R M 1 32 .5 a t W in st on , O re g. , B rid ge ( 1 4 3 1 2 0 0 0 ; D E Q ) C ow C re ek n ea r m ou th b el ow R id dl e, O re g. ( 1 4 3 1 0 0 0 0 ; D E Q ) S ou th U m pq ua R M 1 62 .5 n ea r C an yo nv ill e, O re g. ( D E Q ) S ou th U m pq ua R M 1 65 .5 , 4. 5 m ile s ea st o f C an yo nv ill e, O re g. ( D E Q ) S ou th U m pq ua R M 1 70 .2 a t D ay s C re ek , O re g. ( 1 4 3 0 8 6 0 0 ; U S G S ) " D ra in ag e ba si n bo un da ry C ou nt y bo un da ry ^. ,, ' " C O U N T Y

Analysis of fixed-station water-quality data in the Umpqua River basin, Oregon