Preliminary Results of Hydrogeologic Investigations in the Valley of the Humboldt River Near Winnemucca, Nevada GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1754 Prepared in cooperation with the Nevada Department of Conservation and Natural Resources Preliminary Results of Hydrogeologic Investigations in the Valley of the Humboldt River Near Winnemucca, Nevada By PHILIP COHEN GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1754 Prepared in cooperation with the Nevada Department of Conservation and Natural Resources UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1964 UNITED STATES DEPARTMENT OF THE INTERFOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY Thomas B. Nolan. Director The U.S. Geological Survey Library cards for this publication appear after page 59 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C., 20402 CONTENTS Page Abstract _________________________________________________________ 1 Introduction._____________________________________________________ 2 Location and general features of the area.________________________ 2 Scope of the investigation and purpose and scope of the report._____ 3 Previous work_____________________ __________________________ 4 Acknowledgments _____________________________________________ 4 Numbering system of wells and test borings ______________________ 5 Methods of investigation. __________________________________________ 5 Field program.______________________________________________ 5 Laboratory studies____________________________________________ 7 Geology._______----_-----_--_-___-__________________________-____ 8 Geomorphic features----_-----__-_________-_--_.__-________-___ 8 Mountains- _______________________________________________ 8 Upland erosional surfaces and alluvial fans______---_-____-_-_ 9 Physiographic features formed by Lake Lahontan_____________ 9 Streams and associated geomorphic forms___________________ 11 Humboldt River______________________________________ 11 Little Humboldt River_-__________-_-____--______--__ 13 Small tributary streams__----_-_------__------_-------- 14 Lithology and water-bearing character of the rocks________________ 15 Consolidated rocks._______________________________________ 15 Rocks of Paleozoic and Mesozoic age. ___________________ 15 Rocks of Cenozoic age___ ___-___-___-______-_-______-__ 15 Rocks of late Tertiary and Quaternary age_______________ 15 Unconsolidated rocks______________________________________ 18 Pre-Lake Lahontan deposits.___________________________ 18 Lake Lahontan deposits._______________________________ 19 Lower silt and clay unit.________-___-___-__--_----_ 19 Alluvium-. _________________________________ 20 Medial gravel unit...________-__-______-__-_-_---__ 20 Upper silt and clay unit.___________________________ 23 Gravel-bar deposits-____________-_________--_-_---- 27 Post-Lake Lahontan deposits.__________________________ 27 Terrace deposits___-------_----_-____------___-_-_- 27 Fluviatile and subaerial deposits of the meander-scroll plain__________-___-_____.___________ 28 Fluviatile and lacustrine deposits.___________________ 29 Younger fanglomerate______________-_-___-___---- 29 Windblown deposits.. _________-_-_____________---- 30 Structural geology._------__-_______________-,____-__---__----- 30 nr IV CONTENTS Page Surface water.__----_--____________________._____________-_-__--_- 31 Humboldt River....____________________________________ 31 Comus gaging station._____________________________________ 31 Rose Creek gaging station _____________________________1__-- 32 Winnemucca gaging station________________________---__--_- 33 Relation between streamfiow at the Comus and Rose Creek gaging stations._________________________________________ 33 Seepage gains and losses along the Humboldt River.___________ 36 Other streams.._______________________________________________ 40 Ground water_____________________________________________________ 40 Principles of occurrence._______________-_____-_-_______--__-_-_ 40 Occurrence and movement of ground water._______-__-___--_-_--- 43 Ground-water recharge________________-____-_____-_---___-_ 43 Preliminary estimates of underflow from tributary areas____ 44 Grass Valley and the northwestern slope of the Fonoma Range__ _ ____________________________________ 45 Paradise Valley__________________-__-___--___---_ 46 Pole Creek-Rock Creek area________________________ 47 Valley of the Humboldt River upstream from the study area.__________________________________________ 47 Summary of underflow from tributary areas___________ 48 Seepage losses from the Humboldt River________-___-_-_- 48 Recharge resulting from irrigation _______________________ 49 Direct precipitation on the valley floor ___________________ 50 Ground-water discharge_____-----__--_-____--__-__-----_-_- 50 Underflow near the Rose Creek gaging station_____________ 50 Effluent seepage to the Humboldt River._________________ 50 Evapotranspiration_ _ __ _ _______________________________ 51 Changes of ground water in storage._________________________ 52 Specific retention._____________________________________ 52 Porosity._____________________________________________ 53 Specific yield________________________________________ 53 Changes related to rising ground-water levels____________ 55 Summary and conclusions__ _________-___--___-_____-_-____-_-__--__ 58 References cited___________________________________________________ 58 ILLUSTEATIONS [Plates are in separate volume] PLATE 1. Map of the Humboldt River drainage basin, Nevada, slewing area of this report. 2-4. Maps of the valley of the Humboldt River near Winnemucca, Nevada, showing 2. Geology and location of test borings, observation wells, and streamflow measuring stations. 3. Generalized water-level contours in December 1961. 4. Ground-water storage units. CONTENTS V Page FIGURE 1-2. Medial gravel collected from test boring 35/36-15dacl: 1. Unsorted and unwashed___________________________ 22 2. Sorted according to degree of roundness_____________ 23 3. Medial gravel collected from test boring 35/36-15ddbl._ __ 24 4 5. Generalized geologic sections: 4. Upper silt and clay unit________________________.__ 25 5. Lahontan gravel bar_________________.____________ 26 6. Streamflow measurements along the Humboldt between the Comus and Rose Creek gaging stations_______________ 38 7. Divisions of subsurface waters__________________________ 41 8. Histogram showing the frequency distribution of specifn- yield values____________.___________________________ 54 TABLES Page TABLE 1. Summary of test drilling in the valley of the Humboldt River near Winnemucca, Nev., 1959-60.______________________ 7 2. Lithology and distribution of the rocks of Paleozoic and Meso- zoic age in and near the valley of the Humboldt River near Winnemucca, Nev___________________________________ 16 3. Streamflow of the Humboldt River at the Comus gaging sta­ tion. _____________...__________._-__-_ 33 4. Monthly and yearly streamflow of the Humboldt River at tt 3 Comus and Rose Creek gaging stations, 1949-60 ________ 34 5. Designation and location of streamflow measuring stations aloro; the Humboldt River, near Winnemucca, Nev__________ 37 6. Streamflow measurements along the Humboldt River between the Comus and Rose Creek gaging stations, 1959-61 ______ 39 7. Streamflow at the Pole Creek gaging station, 1956-60. __ _ 40 8. Preliminary estimates of underflow through selected sectiors perpendicular to the Humboldt River._________________ 45 9. Laboratory specific-yield values of sediment samples from tte valley of the Humboldt River near Winnemucca, Nev____ 54 10. Ground-water storage units and short-term specific-yield values for rising ground-water levels in the valley of th^ Humboldt River near Winnemucca, Nev______________ 56 11. Increase of ground water in storage resulting from rising ground-water levels during April, May, and June in thi valley of the Humboldt River near Winnemucca, Nev____ 57 PRELIMINARY RESULTS OF HYDROGEOLOGIC INVESTIGATIONS IN THE VALLEY OF THE HUMPOLDT RIVER NEAR WINNEMUCCA, NEVADA By PHILIP COHEN ABSTRACT Most of the ground water of economic importance and nearly all the ground water closely associated with the flow of the Humboldt River in the 40-mile reach near Winnemucca, Nev., are in unconsolidated sedimentary deposits. These deposits range in age from Pliocene to Recent and range in character from coarse poorly sorted fanglomerate to lacustrine strata of clay, silt, sand, and gravel. The most permeable deposit consists of sand and gravel of Lake Lahontan age the so-called medial gravel unit which is underlain and over­ lain by fairly impermeable silt and clay also of Lake Lahontan age. The ultimate source of nearly all the water in the study area is prec'citation within the drainage basin of the Humboldt River. Much of this water reaches the study area as flow or underflow of the Humboldt River and as underflow from other valleys tributary to the study area. Little if any flow from the tributary streams in the study area usually reaches the Humbold*: River. Most of the tributary streamflow within the study area evaporates or is transpired by vegetation, but a part percolates downward through unconsoli­ dated deposits of the alluvial fans flanking the mountains and move* down- gradient as ground-water underflow toward the Humboldt River. Areas that contribute significant amounts of ground-water underflow to the valley of the Humboldt River within the study area are (1) the valle^ of the Humboldt River upstream from the study area, (2) the Pole Cre?k-Rock