Western States Water Council Ground Water in the West Conference Amarillo, TX December 3-5, 2003 Hugh Ricci, P.E. State

1. MANAGING GROUNDWATER Western States Water Council Ground Water in the West ConferenceAmarillo, TXDecember 3-5, 2003 Hugh Ricci, P.E. State Engineer Nevada Division of Water Resources

2. STAFFING • ~80 people in 3 offices – main office in Carson City • ~60 engineers/technicians • ~20 clerical/support staff • Seasonal help for water distribution • Hearing Section Chief is an attorney • 2 Deputy Attorneys General

3. BEAN COUNTING • Receive ~100 applications per month • ~80% of the applications are changes of existing rights • Application No. 70000 was submitted in May 2003 • An additional ~9400 vested and reserved claims

4. WATER LAW IN NEVADA Prior Appropriation Doctrine • First in time, first in right, • Beneficial use is the limit of the water right, • Use it or lose it vs. Riparian Doctrine

5. S.E. CRITERIA FOR APPROVING AN APPLICATION • 4 criteria • Water available from proposed source • Does not conflict with existing rights • Cannot prove detrimental to the public interest • Protectible interest in domestic wells - 2001

6. OTHER IMPORTANT CONCEPTS • Supplemental Rights – two or more rights used together for an intended use. • Comingled Rights – where more than one source, e.g. s.w. and g.w. or g.w. and effluent, are used together simultaneously for an intended use • Preferred Uses – Manner of uses designated as such by the State Engineer, e.g. Municipal, Commercial etc.

7. DOMESTIC WATER WELLS • A water right application and permit are not required in order to drill a domestic well • Domestic purposes as defined under our statutes extends to culinary and household purposes, in a single family dwelling, the watering of a family garden, lawn and the watering of domestic animals • The maximum daily draught is limited to 1,800 gallons per day (2.02 acre-feet per year)

8. 232 Individual Groundwater Basins of which 119 are Designated or Partially Designated

9. 232 Groundwater Basins

10. Perennial Yield • Can be defined as the maximum amount of ground water than can be salvaged each year over the long term without depleting the ground water reservoir

11. Perennial Yield • Beginning in the early 1950’s, Water Resources and the USGS entered into a series of cooperative agreements whereby the USGS studied every basin and produced a reconnaissance report that estimated the perennial yield of that basin.

12. Perennial Yield • Original analysis based on the Maxey-Eakin Method using precipitation-elevation data. • New method of analysis is called the ‘PRISM’ Method of determining precipitation. Greater perennial yields have been our experience with this method (2 to 3 times greater).

13. GROUNDWATER * 1.7 Million Acre – Feet 232 Groundwater Basins EFFLUENT GEOTHERMAL * Perennial Yield of Valley-Fill Reservoirs

14. How Did the Basins get Overdrafted? • Some were already over appropriated prior to the USGS data available (keep in mind that P.Y’s are as low as 200 acre-feet). • New data changed PY’s • Popular thinking that not all rights would be put to their maximum beneficial use. • In the case of Las Vegas Valley, purposely allowed to overdraft (revocable) with the hope that infrastructure would eventually be in-place to deliver Colorado River water and the over pumping would be curtailed.

15. How Did the Basins get Overdrafted? • On paper, some basins are ‘over appropriated’ but that may be due to the issuance of supplemental groundwater to existing surface water sources. Only over drafting in drought years. • Additional allocation of the source may be allowed based on the estimated recharge to the basin from irrigation (~30%)

16. Artesian Well - Well #3, Circa 1941

17. EXAMPLES

18. Carson Valley • PY is 45,000 AFA • GW permits total 100,000 AFA • 60,000 AF supplemental to SW (Carson River) • Actual pumpage in drought years is ~29,000 AF and ~20,000 in wet years.

19. Las Vegas Valley * PY of Las Vegas ValleyDOES NOTinclude secondary recharge from the 300,000 AF of Colorado River brought into the basin.

20. Las Vegas Valley • Of the pumpage, ~6000 AF are revocable • ~5000 AF are from domestic wells Important to Note: • SNWA Cooperative Water Project (CWP) • Filed 146 applications in 1989 in 27 basins for the appropriation of 180,000 acre-feet of groundwater • Four permits have been granted • Virgin River – 130,000 afa • Garnet and Hidden Valleys – 2200 afa • California Wash – 2500 afa • Remaining 114 applications have over 3,000 protests

21. Truckee Meadows(Reno/Sparks Area) • PY is 35,000 AFA • Permits issued slightly above PY • Sub-basin Problem • Mt. Rose Fan Area has ~ 18,000 AF appropriated in that one area. • Large concentration of domestic wells. • Only pumping ~4000 AF and experiencing severe declines in the water table.

22. Mine Dewatering • Groundwater must be pumped in order to mine the ore body at great depths • Consumptive Use + Dewater was ~279,000 ac-ft in 2000

23. Gold Mining Nevada ranks 3rd in the world in gold production behind Australia and South Africa. Nevada’s gold reserves are over 75% of the total known U.S. Gold resources. April of 2002, Nevada Mining celebrated the production of the 50 millionth troy ounce of gold produced from the Carlin Trend.

24. Management Tools

25. Tools • Designate ground water basins • Preferred uses • Allows the State Engineer to impose additional conditions and restrictions on water use e.g. well depths, meters, sanitary seals • A water right permit is required to drill a well (other than domestic) in a designated basin. • Forfeiture and Abandonment • Grant changes of irrigation use for consumptive portion only. • Permit Terms and S.E.’s Orders requiring meters on diversions. • Substitutive uses in the case of mine dewatering. • Exchange of treated effluent for potable water

26. Tools • T-Finite Term • Conjunctive Use through banking (TMWA) • Recharge • Have the ability to regulate pumping based on priorities • Monitor the Basins • Pumpage inventories • Groundwater level measurements • Public Input

27. CARBONATE AQUIFER

28. Nevada Salt Lake Utah Las Vegas Arizona

30. Carbonate Pre-pumping

31. Carbonate Post-pumping

32. CARBONATE AQUIFER • Approximately 50,000 square miles in extent • The carbonate-rock sequences are believed to contain significant, but undetermined, quantities of ground water. • In 1984, the USGS proposed a 10-year investigation of the entire Carbonate Terrain. • It has been known since 1984 that to arrive at some reasonable understanding of the carbonate-rock aquifer system, substantial amounts of money would be required to develop the science, a significant period of study would be required, and that without some understanding development of ground water from the carbonate-rock aquifer system would be risky and the resultant effects could be detrimental to existing water rights and the environment.

33. CARBONATE AQUIFER • In 1985, the Nevada Legislature authorized a program for the study and testing of the carbonate-rock aquifer system of eastern and southern Nevada. The program was a cooperative effort between the State of Nevada and the Federal Government. The overall plan for the program was to study the carbonate-rock aquifers of southern, east-central, and northeastern Nevada as separate phases of work, with a summary of findings to be prepared at the end of each phase. A summary report brought together results from more than 20 technical reports produced during the study.

34. CARBONATE AQUIFER • Investigation of the carbonate-rock aquifer system is additionally complicated by factors including that: • Basic hydrologic data such as ground-water levels in the basin-fill aquifers and the carbonate-rock aquifers, reliable flow measurements for important springs and major streams are scarce or infrequently obtained in much of the area; • Secondary hydrologic and other data, such as hydraulic parameters, geophysical and geochemical, are lacking in many areas; • The geometry, properties, and boundaries of the carbonate-rock and basin-fill reservoirs are generally unknown, and definition of these properties can be expensive and difficult; • Climatic conditions today are inadequately defined (particularly at higher altitudes) and conditions during the development of the flow paths within the deep-rock aquifers and flow paths are even more uncertain;

35. CARBONATE AQUIFER • Uncertainties and inaccuracies exist in current methods of estimating precipitation; • Uncertainties and inaccuracies exist in current methods of estimating ground-water inflow and recharge; • Uncertainties and inaccuracies exist in current methods of estimating ground-water outflow and evaporative discharge; • Only a small number of wells tap the deep carbonate-rock aquifer system; • Because there has been no significant historical pumping of ground water from the carbonate-rock aquifer system, ground-water models can only be used as a limited predictive tool for estimating the principle location and magnitude of the impacts of pumping ground water from the system; • Limited stresses on the water resources of the area under current development conditions allow hydrologists information only on the narrow band of system responses to natural conditions; and • The relationship between geothermal systems and the deep carbonate-rock aquifers and ground-water flow systems is not well understood.

38. CARBONATE AQUIFER • S.E. issued Order 1169 on March 8, 2002 • Stated that all applications pending and any new filings for water from the carbonate in the 6 basins in question, will be held in abeyance until further information is obtained by stressing the aquifer by those water right permits already issued from the carbonate. • Ordered a 5-year hydrologic study to be conducted during which at least 50% of the currently permitted water rights (~16,000 acre-feet) are pumped for at least 2 consecutive years. The cost of the study will be paid for by the 5 entities currently pumping from the carbonate aquifer.

39. CARBONATE AQUIFER • S.E. issued Order 1169 on March 8, 2002 • The S.E. will facilitate meetings between his office and the 5 entities concerning the scope of the study. • Requires each entity to exchange with each other on a quarterly basis, the rate at which water was diverted, total acre-feet diverted per month and monthly water levels measurements. • Within 180 days after the study period, a report must be filed with the S.E. as to the information obtained and any impacts seen to the groundwater or surface water resources of the carbonate or alluvial aquifers. • After the S.E. reviews the report, he will then make a determination as to whether he has sufficient information to proceed with ruling on the pending applications.

40. Thank You,Questions? http://water.nv.gov