DECISION SUPPORT TOOL FOR THE WALKER RIVER BASIN

Greg Pohll March 29, 2015

Walker Lake | Credit: Jeff Gersh (Narrative Labs)

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Walker Basin

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The Walker Basin Restoration Program (WBRP) was established by Public Law 111-85 (2009) for the primary purpose of restoring and maintaining Walker Lake, and to protect agricultural, environmental and habitat interests in the Walker Basin consistent with that primary purpose.

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PRMS models of headwater areas (Supply Side)

MODSIM River Basin Management system

MODFLOW models for Mason, Smith, & lower Walker (Demand Side)

Economics Model Lake M

odel

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River Inflows

River Outflows

HRUs

Surface Diversions

Ditch Leakage

Return Flows

Irrigation Recharge

Groundwater System

Stream & Drain Flow Exchange with Groundwater

Non-Ag ET (lost from system)

River/Drain Network

Crop ET (lost from system)

Groundwater Pumping

(Storage) Interbasin Groundwater flow

Interbasin Groundwater flow

Mtn Block Recharge

y = 0.3211x - 857.69 R² = 0.7096

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5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

0 20,000 40,000 60,000 80,000 100,000 120,000

Net

Acc

retio

n/D

eple

tion

(acr

e-ft/

yr)

Previous Year Groundwater Pumping Volume (acre-ft/yr)

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Groundwater Models

Mason Valley

Smith Valley

Bridgeport

East Walker

Lower Walker

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Walker Lake Predictions

Data Collection

March 29, 2016 DRI – Science. Environment. Solutions.

River discharge Groundwater levels Lake stage and TDS concentration TDS loading to Walker Lake

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