Designated Basins in Nye County

Nye County's Hydrographic Regions, Basins, and Sub-basins are listed on the Nevada Division of Water Resources website NDWR.  There are 44 basins in Nye County, of which 27 are shared with other Nevada counties and 2 are shared with California.  Twelve of the County's 44 basins are "designated".  By basin number, the designated basins are:

Basin No.
Basin Name
56
Upper Reese River Valley
122
Gabbs Valley
137A
Big Smoky Valley / Tonopah Flat
137B
Big Smoky Valley / Northern Part
141
Ralston Valley
146
Sarcobatus Flat
149
Stone Cabin Valley
161
Indian Springs Valley
162
Pahrump Valley
170
Penoyer Valley
228
Oasis Valley
230
Amargosa Desert
Designated groundwater basins are basins where permitted groundwater rights approach or exceed the estimated average annual recharge into the basin such that the water resources are being depleted or require additional administration.  By designating a basin, the State Engineer is granted additional authority in the administration of the groundwater resources within the designated basin.

However, designation of a water basin by the State Engineer does not necessarily mean that the groundwater resources are being depleted, only that the appropriated water rights exceed the estimated perennial yield.  Actual groundwater use may be considerably less than perennial yield, which is the case for most of the above basins in Nye County (2004 Nye County Water Resources Plan).
The NDWR map titled 
Administrative Groundwater Basins displays the designation status for the groundwater basins in Nevada.  This map is a useful tool to generally determine the basin boundaries and where potential impediments to groundwater development may exist.  Please note that the associated State Engineer's orders and rulings should be examined for a complete understanding of the management issues and water availability within a basin.
DESIGNATION STATUS
GENERAL DESCRIPTION
Designated
State Engineer's order(s) do not define any administrative controls.
Designated - Irrigation Denied
State Engineer's order(s) state that irrigation is not a preferred use in these basins and applications for new irrigation appropriations will be denied.
Designated - Preferred Uses
State Engineer's order(s) list certain types of uses as preferred in these basins, and quantity restrictions may be placed on these preferred uses.
Designated - Preferred Uses;
Irrigation Denied
State Engineer's order(s) list certain types of uses as preferred in these basins.  Quantity restrictions may be placed on these preferred uses.  State Engineer's order(s) also state that irrigation is not a preferred use in these basins and applications for new irrigation appropriations will be denied.  Other uses may also be listed as denied.