In the News...

The Natural Resources Conservation Service (NRCS) is beginning a planning study for upgrading and rehabilitating Dam Site 17of the Brushy Creek Water Shed. This engineering study is being carried out by Freese and Nichols Inc. of Fort Worth Texas under contract to the NRCS Headquarters in Temple Texas. The purpose of the planning study is to evaluate the changes to the dam required to bring the facility into compliance with current NRCS and State of Texas criteria. When originally constructed in the 1960 to 1965 timeframe the Brushy Creek floodplain downstream of the dam was sparsely populated and used for agricultural purposes. The original NRCS design criteria for this low hazard dam was based on the rural setting of the dam. Now that land development along Brushy Creek downstream of the dam makes the rural setting design of this dam no longer applicable, the NRCS is performing this planning study to determine the most cost effective approach for rehabilitating the dam and bring it into compliance with current criteria. The study being performed is federally funded; however, the construction modifications to the dam will be a jointly funded effort with the Upper Brushy Creek WCID providing 35 percent of the rehabilitation construction cost. The study will be conducted in coordination with a Steering Committee made up of interested local landowners, homeowners associations, municipal and county officials. Public information meetings will be held during this four month long study to allow for local interests to be brought to the attention of NRCS officials.

 

The Upper Brushy Creek WCID Board of Directors, at their regular meeting on October 11, 2004, awarded construction contracts to three area companies to improve the flood protection capabilities at three of the District's existing dam locations, and install the first phase of the District's Early Warning System. The District has twenty-three (23) dams between Leander and Hutto, located along tributaries of Brushy Creek in southern Williamson County. These structures were designed and built with assistance from the Federal Government between 1959 and 1967 and twenty-two (22) of these structures do not meet current State of Texas Dam Safety Regulations. These contracts mark the beginning of an intensive construction program estimated to need between ten (10) to twelve (12) years to complete improvements to all of the remaining Districts dam sites. The first dam site to be improved was dam # 9; construction began in August 2003 and was completed in May 2004. Funding for the construction program comes from a property tax levy of $ 0.02 per $ 100 valuation on all property located within the District’s boundaries. Voters authorized the tax in a May 2002 election.

The District awarded a contract to Dayco Construction Company in the amount of $ 854,626.39 for improvements to dam # 11, located near the intersection of FM 3406 and Sunrise Road, east of IH 35 in Round Rock. The District also awarded a contract to Dayco Construction Company in the amount of $ 553, 698.00 for improvements to dam # 12, located near the intersection of FM 3406 and Creek Bend Blvd., west of IH 35 in Round Rock. The District awarded a contract to C.C. Carlton Industries, Ltd. in the amount of $ 248,125.00 for improvements to dam # 14, also known as Meadows Lake, located near the intersection of FM 3406 and Settlement Drive, east of IH 35 in Round Rock. The District awarded a contract to C. Fowler & Associates in the amount of $ 329,340.60 for installation of six (6) Early Warning System monitoring stations to be located at dams # 9, #11, # 12, #13A, #14, and #19.

 

Final cleaning operations at Dam 13A have successfully cleared all debris from the principal spillway’s intake structure and lake levels have returned to normal. A pack of beavers blocked the pipe by placing tree branches, leaves, and other debris inside the intake structure and outfall pipe. The debris clogs had reduced discharges through the spillway pipe and led to elevated lake levels throughout June and July. Maintenance contractors partially cleared the debris on July 19 and the pipe discharged between 50 and 75% of its capacity until the lake had returned to normal on August 16. Metal barriers will be constructed around the intake structure to prevent futures blockages.

 

Maintenance contractors working for the Upper Brushy Creek WCID, were able to open the principal spillway Monday morning July 19th and allow a significant amount water to start draining out of the lake. The 200 foot section of horizontal 22-inch pipe is flowing approximately 50% to 60% full and discharging approximately 28 to 30 cubic feet per second of water. If the flow of water continues at this rate, it will take approximately 20 days to return the lake level down to it's normal elevation and size. The principal spillway was blocked with debris placed in the pipe by beavers that had migrated into the lake area recently.

The flow of water out of the principal spillway is being monitored daily, and the maintenance contractor has equipment at the site to work on the spillway, if it shows any signs of reduced flow. Williamson County road personnel have been notified to check and monitor the culverts under Sam Bass Road, Walsh Drive, and any other roads downstream of the dam that may be affected by the water. The amount of water flowing out of the pipe is limited by the diameter of the 22-inch pipe and will not exceed any historical discharge levels.

Once the lake returns to normal levels, the entire principal spillway will be cleaned from the inside, and additional barriers will be installed to prevent the beavers from blocking the pipe again.

 

The Upper Brushy Creek WCID is experiencing a problem with the small principal spillway at dam # 13A, which is located at the intersection of FM 1431 and Sam Bass Road. The principal spillway is designed to maintain a lake level at or below elevation 829.4 feet (above sea level) and a surface area of 27 acres or less. If rain increases the lake level, then it is gradually drained out through the 22-inch pipe located under the dam, until reaching the 829.4 foot elevation. Contractors working for the WCID spotted beavers putting small tree limbs and other debris into the principal spillway structure. They have attempted to clear the pipe several times during the month of June, however, the additional rainfall has not allowed access to the top of the pipe and the blockage has reduced the movement of water down to a very small volume.

Because of the record rainfall in June 2004 and the blockage of the pipe, the lake volume has increased to 115 surface acres. This water is taking up space in the flood pool storage area of the dam which would mean that if rainfalls continue in July and/or August at the same levels experienced in June, then the lake level would continue to rise until it reached the level of the emergency spillway 842 feet (above sea level). The top of this dam is 846.5 feet above sea level. Any additional water entering the lake area would then be discharged out the emergency spillway and back into the natural drainage area below the dam at the same point that the principal spillway discharges its water.

In an effort to clear the principal spillway, the WCID brought in commercial divers in early July, they cleared a large amount of debris from the principal spillway, however, because of safety concerns, they could not enter the narrow pipe and remove the remainder of the debris, which is still blocking the principal spillway. The WCID is working on additional solutions to clear the blockage and return the lake level to its normal level as soon as possible.

It is important to understand that there is nothing wrong with the dam structure itself; the dam is working and functioning as it was designed and is in very good condition.

 

On April 28, 2004, the District participated in the annual meeting of the Texas Floodplain Managers Association. The presentation gave an overview of how and why the District was created in 1957 to serve as the local sponsor for construction of flood control dams throughout the watershed. The TFMA presentation went on to discuss current issues the District is facing with an explosion of development in southwestern Williamson County and the resulting impacts on the 23 flood control dams. Other discussion topics included formation of a 10-year dam modernization program, developing revenue sources, and coordination with regulatory agencies and city and county jurisdictions.

 

The Upper Brushy Creek WCID Board of Directors, at their regular meeting of April 5, 2004, appointed Martha Ferrero Juch, P.E., to fill the recent vacancy on the Board. Ms. Juch will serve until May 2006, filling the unexpired term of former Board Member Charles Roth, who recently left the Board after moving outside District boundaries. Ms. Juch lives in Williamson County, is a Certified Floodplain Manager (CFM) and has had her own engineering consulting firm for the past four years, specializing in water resources and floodplain management. Prior to establishing her own company, she had worked for the Harris County Flood Control District for five years, and additionally has eleven years of engineering experience working with local and national consulting firms. Ms. Juch is a member of the Round Rock Chamber of Commerce, participated in Leadership Round Rock 2002-2003, and is active with the Boy Scouts of America.

 

The District is currently developing an Early Warning System (EWS) for citizens in the Upper Brushy Creek watershed. The EWS will consist of a centrally-located base station and remote data collection instruments at each of the 23 dams. The EWS will gather real-time hydrologic data at each dam and transmit it back to the base station. Programmed software at the base station will continuously process the data and emergency personnel will be notified if an emergency condition arises. Once notified, the emergency personnel make decisions about issuing public warnings and initiate Emergency Action Plans (EAPs).

The first phase of the EWS will be to design and construct the base station and data collection instruments for six dams (Dams 9, 12, 13A, 11, 14, and 19) by the end of 2004. The District has budgeted funds to add six dams to the EWS in each of the next three years until all 23 dams are covered.

 

In August 2003, construction began on Dam #9, the first of the District's dams to be modernized. The purpose of the construction project was to raise the top of the dam 18 inches in order to safely pass the 100% PMF without overtopping. Other improvements to the dam included removing trees and vegetation from downstream slopes, repairing the principal spillway plunge basin, placing rock rip rap along the upstream slope, installing a wet well for early warning system instrumentation, and adding permanent survey benchmarks.

The project costs were reduced by an agreement between the District and the Texas Turnpike Authority (TTA). The TTA provided a stockpile of soil, at no cost to the District, that was used to raise the dam; in exchange, the District gave approximately 200 feet of right-of-way for the new State Highway 45 which crosses the dam’s southern abutment. The construction work was performed by Ranger Excavation, Inc. for a total cost of $305,000 and was completed in December 2003.

 

The original Brushy Creek W.C.I.D. was created in 1957 to serve as the local sponsor for projects funded by the U.S. Department of Agriculture’s Soil Conservation Service (SCS). Today, the SCS is called the Natural Resources Conservation Service (NRCS). As a stakeholder in the District’s 23 dams, the NRCS has sponsored an engineering study of two dams, Dams 7 and 13A, to determine what upgrades would be needed for each dam to fully comply with NRCS and State of Texas criteria. See the following press release from November 3, 2003 for more information about the study.

Press Release

FOR RELEASE NOVEMBER 3, 2003

The Natural Resources Conservation Service (NRCS) is beginning a planning study for upgrading and rehabilitating Dam Sites 7 and 13A of the Brushy Creek watershed. This engineering study is being carried out by Freese and Nichols Inc. of Fort Worth Texas under contract to the NRCS Headquarters in Temple, Texas. The purpose of the planning study is to evaluate the changes to the dams required to bring the facilities into compliance with current NRCS and State of Texas criteria. When originally constructed in the 1960 to 1965 timeframe, the Brushy Creek floodplain downstream of the dams was sparsely populated and used for agricultural purposes. The original NRCS design criteria for these low hazard dams was based on the rural setting of the dams. Now that land development along Brushy Creek downstream of the dams makes the rural setting design of these dams no longer applicable, the NRCS is performing this planning study to determine the most cost effective approach for rehabilitating the dams and bring them into compliance with current criteria. The study being performed is federally funded; however, the construction modifications to the dams will be a jointly funded effort with the Upper Brushy Creek WCID providing 35 percent of the rehabilitation construction cost. The study will be conducted in coordination with a Steering Committee made up of interested local landowners, homeowners associations, municipal and county officials. Public information meetings will be held during this four month long study to allow for local interests to be brought to the attention of NRCS officials.