Central Texas Drought and Floods,The Austin Region’s Response

Daryl Slusher, Assistant DirectorAustin Water

September 28, 2015

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• Public utility owned by City of Austin

• Water, Wastewater and Reclaimed Water Utility

• 900,000+ population served

• 3 water treatment plants

• 2 main wastewater treatment plants, Hornsby Bend Biosolids Plant

• Water rights and long term contracts for more than twice the water Austin is currently using– from the “other” Colorado River,

sole source of Austin’s drinking water

Austin Water

South Austin Regional Wastewater Treatment Plant

Ullrich Water Treatment Plant

51st Street Reclaimed Water Tank

Water supply lakes for Austin and Central Texas

Austin’s Drinking Water Reservoirs: Lakes Travis and Buchanan

Image Courtesy of LCRA

Lake Travis, before the drought

In drought

Central Texas Drought:

The Numbers

Drought chronology• Drought began 2008

• Temporary relief with wet year in 2010

• Followed by one of hottest and driest years in Texas history, 90 days over 100 degrees

• Dry years continue, drought determined worse than legendary 1950s Texas “Drought of Record”

• Lakes sunk below one-third full, but did not hit emergency level of 30% / 600,000 acre-feet

• Heavy rains and flooding Memorial Day weekend May 2015

• Lakes now at 73%; Austin continues Stage 2 drought restrictions

19522015

Historical Drought Trends

2010

Calendar Year Totals, ac-ft

Inflows in 2011 were

11% of Average

Average 1,216,2952011 127,8022012 393,1632013 215,1382014 209,023

Higher Rainfall but Lower Inflow: A Climate Paradox• Rainfall slightly more in lake watersheds than in 1950s

Drought of Record, yet inflows dramatically lower

• Possible explanations

– Higher temperatures leading to more rainfall absorbed into the ground

– Upstream impoundments like stock tanks reducing inflow to the lakes

• Even with similar amounts of precipitation, the future may mean reduced water availability.

~1.3M acre-feet Behind the 1950s

Drought of Record

(Lakes full at 2.01M acre-feet)

We are in Uncharted Territory.

Drought Response:

Building Resiliency

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Multi-Faceted Drought Strategies Strengthened water conservation programs in 2007 including two

day per week mandatory watering restrictions

Moved to Stage 2 restrictions in 2011, including one day per week watering

Further strengthened Drought Contingency Plan in 2012

Unprecedented curtailment of downstream agricultural users i.e. rice farmers, beginning 2012

2007 Water Conservation Task Force Recommendations: Ten-Year EstimatedPeak Day Savings

Mill

ions

of G

allo

ns p

er D

ay

1.2.3.4.

Unprecedented Curtailment of Agricultural/Interruptible Customers

• State-approved Emergency Orders curtailed agricultural releases in 2012, 2013 and 2014

• New Water Management Plan pending at state

Austin’s Stage 2 Restrictions

• Outdoor watering limited to one day per week

• No home washing of automobiles, wash at commercial facilities only

• Charity car washes prohibited

Austin’s Stage 2 Restrictions, continued

• No operation of ornamental fountains with aerial spray or water fall >4”

• Commercial patio misters 4pm-12am only

• Austin in Stage 2 for 46 of last 48 months, including currently

Reclaimed: Austin Water’s 3rd Utility

South Austin Regional

Wastewater Treatment

Plant

Interdepartmental and Interagency Coordination • Austin Energy is Austin

Water’s sister utility

• Fuel mix is approximately 20% renewable, and then roughly one-third gas, nuclear and coal

– One gas plant supplied with reclaimed water and the other with river water with potential to switch to reclaimed

• Power distribution is handled on statewide basis by ERCOT, Electric Reliability Council of Texas

Interdepartmental and Interagency Coordination - 2• Emergency planning and

response coordinated through Emergency Operations Center

– Includes law enforcement, first responders, utilities and other local and state agencies

– Climate studies

• Power outages during Memorial Day flooding, Austin Energy traditionally has very rapid response

– Austin Water renewable energy production:

– solar roof of major service center Hornsby Bend powered by methane cogeneration

GPCD on the decline in Austin!

Water Conservation & Drought Response Alter Traditional Financial Patterns

Traditional Pattern

Dry Year Wet Year

New Pattern

Dry Year Wet Year

$ $

$

Moving to Augment Water Supply • Walter E. Long (Decker) Lake: Convert to off-channel reservoir

• Lake Austin: Fluctuate level of constant level lake

• Lady Bird Lake: Capture local inflows and pipe water upstream.– Considering indirect potable reuse in Drought Stage 4.

Walter E. Long (Decker) Lake

Moving Forward

• Planning for hotter and drier climate with increased extremes

• Continue with Colorado as sole source?

– Citizens task forces urge locally-based solutions– Integrated Water Resources Plan

• Considering permanent one day per week restrictions

• Ongoing shift to drought tolerant landscapes

• Increasing use of renewable energy, especially solar

Questions

Contact:Daryl Slusher

Daryl.slusher@austintexas.gov512-972-0218

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• Extra Slides

The Arithmetic of Drought Response and Conservation – Impact on Rates• Drought response and conservation lower

revenues

• Treating and delivering less water reduces some costs (e.g., treatment chemicals and pumping)

• But savings nowhere near lost revenue

• Treatment plants, pumping stations, other infrastructure must still operate

• Water must still be delivered to all customers through underground pipes to every faucet

• Consequently, fixed costs are very high portion of overall costs

South Austin

Regional Wastewater Treatment

Plant

Ullrich Water Treatment Plant

• Adjusting water use projections downward, assuming permanent changes

• Maintaining residential conservation block rate structure that charges big users more

• Increasing fixed revenue goals and fixed charges, beginning in 2012– Goal: 20% in FY15 and 25% recommended for FY16 (was 12% in FY11)

• New Stage 3 Drought Surcharge: $1.00 per 1000 gallons

• New Stage 4 Drought Surcharge: $3.00 per 1000 gallons

• Ongoing discussions about major changes in business model

Restructuring Revenues

Multi-Faceted Drought Strategies Strengthened water conservation programs in 2007

including two day per week mandatory watering restrictions

In 2012 strengthened existing Drought Contingency Plan

Staged phase in of drought restrictions based on lake levels

Curtailment of of interruptible customers i.e. downstream rice farmers, by Lower Colorado River Authority

Moved to augment water supply

Restructuring of revenues

Developing an Integrated Water Resources Plan