INSIGHT INTO CONTINUING CHALLENGES ON THE

COLORADO RIVER

2015 AWRA Annual Conference Jim Lochhead – CEO/Manager – Denver Water

• The Colorado River travels 1450 miles through 7 states and Mexico to the Sea of Cortez

• It supplies water to 40 million people and 5.5 million acres of agriculture.

• $1.7T in gross municipal product = 12th economy in the world

• Total use 80% agricultural, 20% M&I • The system relies on two large

regulating reservoirs: – Lake Powell in the Upper Basin – Lake Mead in the Lower Basin

Colorado River System

• Divided the Colorado River, including all tributaries, into an Upper and Lower Basin

• Boundary between the two basins is Lee Ferry, Arizona • Lower Basin states: Nevada, California and Arizona • Upper Basin states: Wyoming, Colorado, New Mexico and Utah • Arizona, Utah and New Mexico have lands within both basins

1922 Colorado River Compact

Total Allocation of 18 MAF • 8.5 MAF to the Lower

Basin – 4.4 MAF to California – 2.8 MAF to Arizona – 0.3 MAF to Nevada – 1 MAF from LB

tributaries • 7.5 MAF to the Upper

Basin – 51.75% to Colorado – 23% to Utah – 14% to Wyoming – 11.25% to New Mexico

• 1.5 MAF to Mexico

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Colorado River Compacts and Treaty

Colorado River Compact signing

An over-allocated river Colorado River water supply vs use

Built-in imbalance and problems

• Upper Basin: Hydrologic leftovers – Upper Basin to not

deplete flow at Lee’s Ferry below 75 MAF over running 10 yr. average

– Over allocation, growth and climate change all combine to create uncertainty of supply for Upper Basin

“Bath tub ring” at Lake Powell

Built-in imbalance and problems • Lower Basin: Structural Deficit

– Inflow into Lake Mead = 9.0 maf (8.23 maf release from Powell + side inflows) – Outflow = -9.0 maf (AZ, CA, NV and Mexico Delivery – System and evaporative loss = -1.2 maf – Deficit = -1.2 maf

Given basic apportionments in the Lower Basin, the allotment to Mexico and an 8.23 maf release from Lake Powell, Lake Mead declines about 12 feet/year.*

*Bureau of Reclamation

Collaboration to create flexibility

Key accomplishments • 1996 – Interstate banking – NV in AZ • 2001 – Interim Surplus Guidelines • Quantification Settlement Agreement – CA down to 4.4 maf

allocation • 2007 Shortage Sharing/ Interim Operating Guidelines

– Resolves operating issues – Upper Basin tied to Lower Basin structural deficit

• 2012 – Minute 319 brings Mexico into shortage sharing and adds NGOs to discussion

Lake Powell and Mead operational table

Historic drought continues

Current Storage

Percent Full MAF Elevation (Feet)

Lake Powell

51 12.4 3606

Lake Mead

38 9.9 1079

Total 45 22.3 n/a

As of November, 2015

Projected future supply and demand

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Contingency planning

• CRSP reservoir operations • Demand management • Colorado River System Conservation Plan

– Provides up to $11 million funding for at least two years to develop, test and gather data on short-term water-saving pilot programs to benefit water levels in lakes Powell and Mead

– Temporary, voluntary and fully-compensated programs – Programs should be designed to reduce consumptive use of

water – All water conserved under this program will be treated as river

system water. The saved water will not go directly to the program funders or other water users

– Pilot programs already underway

Future challenges

• Climate change – what will it mean? • Growth – a real threat? • Hydro-electric power • The need for innovation, a basin-wide approach,

diplomacy – Upper Basin – developing a contingency plan – Lower Basin – solving the structural deficit – Realizing basin wide synergies