River Operations Report - Water Supply Operations

Summary

This River Operations report provides current information about LCRA's daily water supply operations. 

LCRA posts the latest information about flood operations in the Flood Operations Report when conditions warrant.  

You can navigate to specific sections of the River Operations Report using the links below:

Data presented on this web page includes provisional data obtained by LCRA for the use of its professional staff. This data is retrieved and displayed automatically, and is subject to revision.

Current Operations and Conditions
Last Update: 7/26/2016 7:37 AM

LCRA’s operation of the Highland Lakes is governed by the 2015 Water Management Plan.

The plan, approved by the Texas Commission on Environmental Quality in November 2015, protects the water supply for firm customers – mainly cities and industrial users – and allows LCRA to quickly adapt its operations as drought conditions change. The plan establishes three sets of operating conditions to determine the availability of interruptible stored water, which is primarily used by agricultural customers in Colorado, Wharton and Matagorda counties. It also sets two dates – March 1 and July 1 – for determining the amount of interruptible stored water available for first and second crop.

Under the 2015 Water Management Plan, a limited amount of interruptible stored water is available for first crop agricultural uses in the lower basin from mid-March through about mid-August in 2016. This is the first time Highland Lakes water has been available for most interruptible water customers since 2011.  The managed storage of lakes Buchanan and Travis on July 1 was 1,964,073 acre-feet.  Based on this water supply condition, additional water will be made available for second crop through mid-October. The water will be released gradually and only to the extent the needs for agriculture cannot be met with the natural flow of the Colorado River. The needs for agriculture and the flow of the river will depend on weather conditions during the irrigation season.

LCRA conducts water supply operations consistent with the Water Management Plan and all other applicable water rights and agreements. During water supply operations, needs for water are first met with the natural flow of the Colorado River - to the extent allowable - to reduce the amount of water used from the Highland Lakes.  Water also may be released from any of the Highland Lakes as needed to manage excess flood waters.

Releases from Lake Austin are made when needed to meet downstream customer needs, and to supplement the flow of the lower river when needed to meet environmental flow requirements.  Customers that take water from the Colorado River downstream of Lake Austin include four irrigation systems (the Lakeside, Garwood, Pierce Ranch and Gulf Coast systems), the Fayette Power Project, industrial customers in Matagorda County, the City of Pflugerville, Decker Creek Power Station, Lost Pines Power Park and others.  Environmental flow requirements include TCEQ requirements to maintain instream flows along the lower Colorado River and supply freshwater inflows to Matagorda Bay and estuary.

Releases from Lake Travis are made when needed to replace water that is released from Lake Austin, and to supply water to customers along Lake Austin. Customers that take water from Lake Austin include the City of Austin, West Travis County Public Utility Agency and others.

Releases from Lake Buchanan are made when needed to replace a portion of the water that is taken or released from Lake Travis, and to supply water to customers along lakes Inks, LBJ, and Marble Falls.  Customers that take water from the Highland Lakes above Mansfield Dam include the City of Austin, City of Cedar Park, Travis County WCID No. 17, City of Leander, Lakeway MUD, Ferguson Power Plant and others.




Current Lake Levels
Lake (Dam)Date/Time of Last ReportLake Level
(ft msl)
7 Days Ago
(ft msl)
30 Days Ago
(ft msl)
Buchanan (Buchanan)7/27/2016 2:30 AM 1017.75 1017.811018.04
Inks (Inks)7/27/2016 2:30 AM 887.21 887.36887.31
LBJ (Wirtz)7/27/2016 2:30 AM 824.65 824.68824.73
Marble Falls (Starcke)7/27/2016 2:30 AM 736.35 736.29736.48
Travis (Mansfield)7/27/2016 2:30 AM 679.29 679.85681.12
Austin (Miller)7/27/2016 2:30 AM 492.13 492.11492.12


Highland Lakes Profile Click to view dynamic Highland Lakes System Profile
Click to view webpage.


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07/26/2016 7:37 AM

Short term lake level forecasts for Buchanan and Travis:

Buchanan
Tomorrow = 1017.7 ft msl
One Week = 1017.6 ft msl

Travis
Tomorrow = 679.2 ft msl
One Week = 678.6 ft msl




Current Storage In Lakes Buchanan and Travis
LakeDate/Time
of Last Report
Lake Level


(ft msl)
Historical
July
Average
(ft msl)
Difference
From
Average
(ft)
Storage
When Full

(ac-ft)
Current
Storage

(ac-ft)
Current
Percent
Full
%
Difference
From Full

(ac-ft)
Buchanan 7/27/2016 2:30 AM1,017.751,012.515.2 875,588 826,468 94 % -49,120
Travis 7/27/2016 2:30 AM679.29666.9912.3 1,134,956 1,102,459 97 % -32,497
Totals 2,010,5441,928,92796%-81,617

Lake Buchanan is currently being managed to a maximum storage level of 1,018 feet msl.  Under an agreement with the Federal Emergency Management Agency, conservation storage is limited to this elevation in the more flood-prone months of May through October.  LCRA is currently limiting storage year-round while upgrades to the floodgates are underway. Read more about the management of Lake Buchanan.



Upstream Flow Conditions and Gauged Inflows
LocationDate/Time
of Last Report
Current Flow


(cfs)
Previous Day
Average Flow

(cfs)
Inflow Runoff
Factor
Previous Day
Adjusted
Average Flow
(cfs)
Previous Day
Gauged Inflow
Volume
(ac-ft)
Colorado River near San Saba 7/27/2016 2:40 AM 93.2 941.035 98 194
Llano River at Llano 7/27/2016 2:40 AM 69.1 661.000 66 132
Sandy Creek near Kingsland 7/27/2016 2:40 AM 0.0 02.367 0 0
Pedernales River near Johnson City 7/27/2016 2:40 AM 49.5 522.030 106 209
Previous Day Total Gauged Inflows*    270535

Inflows to the Highland Lakes are measured at four streamflow gauges shown in the table above. A runoff factor is applied to the measured flow to account for additional inflows that may occur downstream of each gauge. When the natural flow of the Colorado River upstream of the Highland Lakes is abundant, LCRA stores the excess water in the Highland Lakes, and lake levels rise.


Downstream Flow Conditions
LocationDate/Time
of Last Report
Current Flow

(cfs)
Previous Day
Average Flow
(cfs)
Previous Day
Flow Volume
(ac-ft)
Colorado River at Austin 7/27/2016 2:40 AM 164 402797
Colorado River at Bastrop 7/27/2016 2:40 AM 893 7981,582
Colorado River at Smithville 7/27/2016 2:40 AM 812 8241,634
Colorado River above La Grange 7/27/2016 2:40 AM 1,049 1,0021,987
Colorado River at Columbus 7/27/2016 2:40 AM 1,195 1,2172,414
Colorado River near Altair 7/27/2016 2:40 AM 1,306 1,2302,439
Colorado River at Wharton 7/27/2016 2:40 AM 1,384 1,3352,648
Colorado River near Lane City 7/27/2016 2:40 AM 1,523 1,5743,121
Colorado River at Bay City 7/27/2016 2:40 AM 2,753 2,4894,938

Note: The U.S. Geological Survey's (USGS) Bay City Gauge is strongly affected by tides from the Gulf of Mexico and provisional gauge readings may be inaccurate when flow in the river at Bay City is low, below about 2,300 cfs.  Provisional data is subject to revision by the USGS.




Previous Day Releases
Lake (dam)Approximate
Time of Release
Average
Discharge
(cfs)
Discharge
Volume
(ac-ft)
Buchanan (Buchanan)07/25: No releases00
Inks (Inks)07/25: No releases00
LBJ (Wirtz)07/25: No releases00
Marble Falls (Starcke)07/25: No releases00
Travis (Mansfield)07/25: 9 am-3 pm6181,226
Austin (Miller)07/25: 11 am-3 pm287569

The Average Discharge and Discharge Volume data in the table above are average daily flows and volumes discharged at each dam. 

The schedule for today’s hydroelectric generation is competitive electric market information, and is not available to the public. Water may be discharged suddenly and unexpectedly due to emergency hydroelectric generation or other reasons. Residents should exercise caution and avoid being in the water near the dams.

(Releases from Lady Bird Lake through Longhorn Dam are controlled by Austin Energy, the electric utility for the City of Austin.)



Instream Flow Conditions and Environmental Criteria
LocationCriteria
for Minimum
Flow
(cfs)
Previous Day
Minimum
Flow
(cfs)
Criteria for
Daily Average
Flow
(cfs)
Previous Day
Average Flow

(cfs)
Colorado River at Austin 50187N/A402
Colorado River at Bastrop 427590610798
Colorado River at Columbus N/A 8951,217
Colorado River at Wharton N/A 9061,335

On July 1, 2016, the daily average combined storage of lakes Buchanan and Travis was greater than 1.96 million acre-feet. In accordance with the 2015 Water Management Plan, environmental flow requirements for instream flow are set to Base-Average levels from July 2016 through February of 2017.  The 2015 WMP prescribes daily average flow criteria at Bastrop, Columbus and Wharton and minimum flow values at Bastrop for Base-Average that vary from month to month, as shown above. 

LCRA’s obligation to release water from lakes Buchanan and Travis to help meet Base-Average instream flow levels is subject to the availability of inflows to lakes Buchanan and Travis in excess of senior water rights.  While the Base-Average criteria in effect is subject by the availability of inflows to the lakes Buchanan and Travis, LCRA will continue to meet Subsistence instream flow criteria, including the minimum flow criteria at Austin, using previously stored water if necessary. 


See Chapter 4 of the 2015 Water Management Plan for a more complete description of the instream flow criteria.




Freshwater Inflows to Matagorda Bay
MonthInflow
Category in
Effect
Criteria for
Monthly Inflow
(ac-ft)
Monthly Inflow*
(ac-ft)
Criteria for
Two-Month Inflow
(ac-ft)
Two-Month
Inflow
(ac-ft)
January OP-2 15,000 105,895 52,000315,841
February OP-2 15,000 60,782 52,000166,677
March OP-3 15,000 189,669 164,000250,451
April OP-3 15,000 680,586 164,000 870,255
May OP-3 15,000 811,658 76,0001,492,244
June OP-3 15,000 1,241,816 76,0002,053,473
July OP-4 15,000 205,000 
August OP-4 15,000 205,000 
September OP-4 15,000 205,000 
October OP-4 15,000 205,000 
November OP-4 15,000 133,000 
December OP-4 15,000 133,000 
Annual Total 180,0003,090,406  

The 2015 Water Management Plan describes five inflow categories for freshwater inflows to Matagorda Bay. The inflow category is determined by the amount of water stored in lakes Buchanan and Travis on March 1 and July 1. The lowest inflow category is “threshold”. Threshold category calls for minimum monthly inflows of 15,000 acre-feet. The higher inflow categories are “OP-1” through“OP-4”. The OP-1 through OP-4 categories call for minimum monthly inflows of 15,000 acre-feet, and higher two-month inflows that vary throughout the year.


The daily average combined storage of lakes Buchanan and Travis on July 1, 2016, was greater than 1.95 million acre-feet.  In accordance with the 2015 Water Management Plan, environmental flow requirements for freshwater inflows to Matagorda Bay are set to the OP-4 category from July 2016 through February of 2017. The actual bay inflows for the period March 1 to April 30 of 870,255 acre-feet, have exceeded the three-month Spring freshet total of 246,200 acre-feet.  As a result, the two-month bay inflow criteria for the periods ending in May and June was the “intervening” criteria under OP-3 of 76,000 acre-feet. 


LCRA’s obligation to release water from lakes Buchanan and Travis to meet freshwater inflow needs is subject to the availability of inflows to lakes Buchanan and Travis in excess of senior water rights. 
 
See Chapter 4 of the 2015 Water Management Plan for a more complete description of the freshwater inflow criteria for Matagorda Bay.
*Freshwater inflows to Matagorda Bay are calculated using flow at the U.S. Geological Survey's (USGS) Bay City gauge minus the water diverted from the river downstream of the Bay City gauge. However, the Bay City gauge is strongly affected by tides from the Gulf of Mexico and readings may be inaccurate when flow at Bay City is low, below about 2,300 cfs. At low flows, LCRA estimates the flow at Bay City based on flow at LCRA’s Lane City gauge minus water diverted downstream of Lane City. The Lane City gauge is upstream of the Bay City gauge and is not influenced by tide.




Long-Range Lake Level and Storage Forecasts (Links) Historical Data and Reports (Links) Useful Links
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