VOL. 2, NO. 2 WATER RESOURCES RESEARCH SECOND QUARTER 1966 A RegionalInterbasin Groundwater System in the WhiteRiver Area, SoutheasternNevada THOMAS E. EAKIN Water ResourcesDivision, U.S. GeologicalSurvey, Carson City, Nevada Abstract. A regional interbasin groundwater system including thirteen valleys in south- eastern Nevada is generally identified on the basis of preliminary appraisalsof the distribu- tion and quantities of the estimated groundwater recharge and discharge within the region, the uniformity of dischargeof the principal springs,the compatibility of the potential hydraulic gradient with regional groundwater movement, the relative hydrologic properties of the major rock groups in the region, and, to a limited extent, the chemical character of water issuing from the principal springs. The principal findings are: (1) Paleozoic carbonate rocks are the principal means of transmitting groundwater in the interbasin regional system--the regional transmissibility provisionally is estimated to be about 200,000 gal/day/ft; (2) esti- mates of recharge and discharge show wide discrepanciesin individual valleys, but hydrologic balance with recharge and discharge estimates of about 100,000 acre-ft/yr obtains within the thirteen-valley region; and (3) the dischargeof the Muddy River Springs, the lowest of the three principal spring groups, is shown to be highly uniform, which is consistentwith their being supplied from a large regional groundwater system. The relation between this regional system and others in eastern and southern Nevada is now under study by the Geological Survey. (Key words: I-Iydrologie systems;hydrology (limestone); springs; groundwater) INTRODUCTION a regional groundwater system in a part of the Basin and Range province in southeastern Reconnaissanceappraisals of the groundwater Nevada. Although the scope of the report is resourcesof various valleys in Nevada have been limited by the reconnaissancenature of the in- made for severalyears. One of the assumptions vestigationson which it is based, virtually all on which thesestudies originally were predicated componentsof the hydrologic system are eval- was the generally accepted concept that most uated. hydrologic systemswere more or less co-exten- Locationand extent o)e the reqion. The re- sive with the topographicallyclosed basins in gion discussedincludes the area within the drain- the Basin and Range province. As studies for age divides of six valleys drained by the White various areaswere completed,it becameevident River in Pleistocenetime and seven adjacent that groundwatersystems in certain valleys of but topographicallyseparated valleys. It is in eastern and southern Nevada extended beyond southeastern Nevada and lies within lat 36ø40 ' the limits of the particular valley. Somevalleys and 41ø10'N and long. 114030' and 115ø45'W. have a much larger spring dischargethan could It includesparts of Clark, Elko, Lincoln, Nye, be sustainedby local recharge,and other valleys and White Pine counties (Figure 1). From its have deep water levels that preclude an an- north end in southernElko County, the region nual groundwater dischargeby evapotranspira- extendssouthward to includethe upper Moapa tion comparable with probable local recharge. Valley, a distance of about 240 miles. Its maxi- If these observations are correct, a multivalley mum width is about 70 miles near lat 38øN. regional groundwater system is required to The regionincludes an area of about 7700 square satisfy the general hydrologic equation that in- miles. flow equals outflow. Topographic settinq. Figure 2 shows the This report describesthe general features of locationsof the principal valleys and rangesin the region.Of the thirteen valleys,Long, Jakes, • Publication authorized by the Director, U.S. Cave, Dry Lake, and Delamar valleys are Geological Survey. topographicallyclosed. Garden Valley surfici- 251 252 TI-IONIAS E. EAKIN 116ø00' • 115ø00' 114000' •. •::• / ELKOCOUNTY I I ..:;:;:::;-:.::;-:.:.:; • EXPLANATION r x , i 1. SHEEP RANGE 0 5 15 25 2. BRISTOL RANGE 3. HIGHLAND RANGE 4. EGAN RANGE Scale in Miles 5. HORSE RANGE i'P'illton 6. GRANT RANGE 7. SCHELL CREEK RANGE 8.PAHRANAGAT RANGE 9.ANTELOPE MOUNTAINS i 10.ARROW CANYON RANGE 11 .QUINN CANYON RANGE i I- 12.WHITE PINE MOUNTAINS COUNTY 13. GOLDEN GATE RANGE LINCOLN i 14.15.DELAMARPAHROC RANGERANGE (•) 16.BUTTE MOUNTAINS COUNTYi 17.MAVERICK SPRINGS RANGE 18. MEADOW VALLEY MOUNTAINS 19.WORTHINGTON MOUNTAINS 20. SEAMAN RANGE •lamar (site) 37 • -----4 Altitude zones ,in feet above sea level; CLARKCOUNTY interval, 2000 feet LasVeg 7O00 -- 9000 ,5000 -- 7000 3000 --5000 , UPPER MOAPA '-VALLEY (3000 115•' 4,,)IScale inMiles Fig. 1. Location of regional interbasinground- Fig. 2. General topography of the area of this water systemdescribed in this report. report. Interbasin GroundwaterSystem 253 ally may drain into Coal Valley but together on Figures4 and 6. Theseelements are discussed they form a topographically closedunit. The in the following sections. remaining six valleys were drained by the Geologic setting. The rocks provide the PleistoceneWhite River, then a tributary to the framework in which groundwater occurs and Colorado River system. The six valleys are moves. Groundwater may occur in interstitial White River, Pahroc,Pahranagat, Kane Spring, openings,in fractures,or in solutionopenings in Coyote Spring,and upper Moapa. the rocks. The openingsmay have been formed This regionof mountainsand valleys generally at the time the rocks were deposited or at a has a southward gradient (Figure 2). Along the subsequenttime by œracturing,weathering, or White River Wash the altitude decreases from solution. The distribution and nature of these about 5500 feet in the latitude of Lund to about openingsmay relate generally to other physi- 1800 feet in the vicinity of the Muddy River cal and chemical characteristics of formations Springsin a channeldistance of about 175 miles. or groupsof rocks.Thus, the generalnature and The averagegradient alongthe Wash is about 21 distribution of the rocks in the region permit feet per mile. The White River Wash forms an some inferences regardirg the occurrence and axial topographiclow between Garden and Coal movement of groundwater. valleys on the west and Cave, Dry Lake, and A number of geologicstudies in parts of the Delamar valleys on the east. area df this report have been made. For present The mountains generally are 2000 to 4000 purposes,the reconnaissancegeologic map of feet higher than the floorsof the adjacent valley Lincoln County [Tscha.nzand Pampeyan, 1961], (Figure 2). The crests of the ranges commonly the reconnaissancegeologic map of Clark County exceed 8000 feet above sea level and locally [Bowyet et al. 1958], the general geologicmap exceed10,000 feet in the north part of the area. accompanyingthe guidebookto the geology of In the south part of the area the crests of the east-central Nevada [Boettcher and Sloan, ranges exceed 8000 feet above sea level only 1960] for White Pine and parts of northeastern locally and commonly are less than 7000 feet Nye counties, and unpublished information in altitude. from F. J. Kleinhampl for segments of the region in northeastern Nye County have been TI-IE REGIOl•AL GROUI•DWATER SYSTEN[ most useful with referencelo the areal geology of the region. For the White Pine County part The regional groundwater system includes of the region many of the papers in the guide- both the rocks and the groundwater of the book to the geology of east-central Nevada fined area. It includesthe areas of rechargeand [Boettcher and Sloa.n,1960] are of much value. discharge,storage and transmissionof water, Although not known to crop out within the and geologicunits that control the occurrence area of this report, Precambrian rocks are and movement of water. Semiperchedground- posedin the northern Egan Range east of Long water in the mountains and in the valley fill of Valley, in the Schell Creek Range [Young, at least some valleys contributesto the regional 1960], along the east side of Cave Valley and systembut is not emphasizedherein. northward, and in the Mormon Mountains The identification of this regional ground- [Tschanz and Pampeyan, 1961] east of Coyote water system is based upon (1) the relative hy- Spring Valley and may be inferred to underlie drologicproperties of the major rock groups in all the region of this report. the area of consideration;(2) the regionalmove- A thick section of Paleozoic rocks was de- ment of groundwateras inferred from potential posited throughout and beyond the area. Lo- hydraulic gradients; (3) the relative distribution cally, the stratigraphicthickness of the Paleozoic and quantitiesof the estimatedrecharge and dis- rocksexceeds 30,000 feet [Kellog, 1963, p. 685]. charge; (4) the relative uniformity and long- Clastic rocks occur principally in the upper term fluctuationof the dischargeof the principal and lower parts of the section. Carbonate springs; and (5) the chemical quality of the rocks, which comprise more than half of the water dischargedfrom the principal springs. section,are generally found in the central part Much of the available data pertinent to the of the Paleozoic section. analysisis includedin Tables 1, 4, 5, and 6 and Lower Triassic marine depositsare noted by EXPLANATION Valley fill principallyclay, silt, sand, and gravel; locally may include fresh- water limestone or evaporite;consolidated to unconsolidated. Deposited under subaerial, stream or lacustrine environments. Lower Tertiary deposits involved in deformation; upper