USACE FORT WORTH DISTRICT DAMS AND LAKES: LESSONS LEARNED FROM THE 2007 FLOOD EVENTS. José Hernández 1 Fred Jensen 2 ABSTRACT INTRODUCTION

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1 USACE FORT WORTH DISTRICT DAMS AND LAKES: LESSONS LEARNED FROM THE 2007 FLOOD EVENTS José Hernández 1 Fred Jensen 2 ABSTRACT This paper provides details on the rainfall totals, damages sustained at specific U.S. Army Corps of Engineers (USACE) projects, and damages prevented in each of the affected river basins during the flood events of In addition, actions taken by USACE Fort Worth District (SWF) personnel in monitoring flood elevations and operating the reservoirs, coordinating with State and local entities for emergency management needs, and providing necessary communication with multiple media outlets are documented and analyzed in an effort to become even more efficient and effective in future flood and disaster situations. INTRODUCTION At the beginning of the year 2007, drought conditions prevailed over many areas of the southern plains states after two years of below-normal rainfall. Many of the lakes across Texas were at record low, or near record low, levels and water restrictions were in effect in some regions. The above-average rains during December 2006 and January 2007 provided some relief to the drought. The rains in February over Texas were near normal. By March, the spring rains began in earnest. Heavy rains fell in mid-march, then again in late March, bringing many lakes in the SWF back to, or even above, their conservation pool levels. By late April, a low pressure trough had developed over Texas and Oklahoma, which became almost stationary as it became trapped between two high pressure systems. Slow-moving trains of thunderstorms became frequent occurrences in many areas of mid-texas for the next three months, producing very heavy rainfall in sometimes staggering amounts. In the first seven months of 2007, most stations in North Central and South Central Texas received rainfall equal to or exceeding their normal annual amount. A National Weather Service map illustrating cumulative regional rainfall is shown in Figure 1. A second map, showing peak water surface elevations at each of the SWF reservoirs, is included as Figure 2. Texas experienced two cloudbursts during the month of June worth noting. The first was in mid-month over north Texas and the second was over central Texas in late June. 1 Dam Safety Program Manager, U.S. Army Corps of Engineers, Fort Worth District, Fort Worth, TX 76102, Jose.Hernandez@usace.army.mil 2 Hydraulic Engineer, U.S. Army Corps of Engineers, Southwestern Division, Dallas, TX 75242, Fred.B.Jensen@usace.army.mil Fort Worth District Dams and Lakes 1195

2 Figure 1. National Weather Service Showing Cumulative Regional Rainfall Map Intense rains during the night of June 17 caused flash flooding in the Dallas/Fort Worth Metroplex and in many counties to the north. Over 10 inches of rain was recorded in the city of Gainesville, a remarkable 3.6 inches of which fell within one hour. Several local streams as well as the Elm Fork of the Trinity River jumped their banks and caused considerable local flooding in and around Gainesville. The US Geological Survey gauge in the Elm Fork at Gainesville malfunctioned due to the high flows, but it is estimated that the peak flow was near 72,000 cubic feet per second (cfs). Part of IH-35 had to be closed and nighttime evacuation of residents in Gainesville and Haltom City (a suburb of Fort Worth) became necessary. Approximately 578 properties were damaged in Gainesville and 120 homes were damaged in Haltom City. Six persons lost their lives in the region. Another major event occurred on 26 June, just west of the IH-35 corridor from Austin to the Oklahoma border. Three to five inches of rain was common, but the heaviest rains fell in the area immediately northwest of Austin. Marble Falls recorded 19 inches of rainfall, most of which drained into Lake Travis above Austin. The resulting flood wave had an estimated peak of 240,000 cfs, contributing much to the foot rise experienced by Lake Travis in Nearby Liberty Hill also recorded 18 inches in the same storm, which sent a flood wave of as much as 100,000 cfs down the San Gabriel River into Lake 1196 Collaborative Management of Integrated Watersheds

3 Figure 2. Map Showing Peak Lake Elevations at SWF Reservoirs Fort Worth District Dams and Lakes 1197

4 Georgetown and Granger Lake, forcing a temporary closure to US Highway 183. Both lakes rose dramatically as floodwaters were captured and stored. The 26 June event also saw 5-6 inches of rainfall in western Comanche County, runoff from which set a new flood stage record on the Leon River near De Leon. The river was above flood stage for eight consecutive days, which caused Proctor Lake to fill high into its flood pool. The weather pattern began to break up and revert to a more normal summer regime in early July. ECONOMIC IMPACTS The economic impacts of the flood events under consideration include the positive benefits of flood damages prevented by the existing SWF projects. Other economic impacts, however, include the cost to repair damages to the facilities and recreational infrastructure at each of those projects caused by the flood waters, the lost gate receipts for having to close recreation areas, and the impacts to the local economy for reductions in the numbers of visitors to the recreation sites, who also contribute to the local economic base by providing revenue to other businesses in the vicinity. This section of the report describes the extent of these impacts. A summary table listing flood damages prevented by SWF projects, lost revenues from visitors to SWF lakes, and estimated repair costs to prime facilities and recreational infrastructure is presented on page 9 of this report. Damages Prevented The summary table presents totals for two different time periods. The table s first column, labeled Damages Prevented, June-July 2007, represents damages prevented only during the incident period established by the Presidential Disaster Declaration designated as FEMA-1709-DR. Damages prevented during this period totaled approximately $3.8 billion. A second column tracks damages prevented during the entire report event period, from March to July During the report event period, SWF projects prevented a total of $7.9 billion in damages, with 98 percent of the damages being prevented by projects associated with the Trinity River basin. Table 1 shows total damages prevented in each of the basins in which SWF reservoirs exist. Table 1. Damages Prevented by SWF Projects per River Basin Basin Damages Prevented Brazos $77,105,700 Colorado $10,700,800 Guadalupe $52,124,900 Red $445,700 Trinity $7,771,427,300 Total $7,911,804, Collaborative Management of Integrated Watersheds

5 It is important to note that these estimates may be significantly underestimated since the discharge-damage functions used for these estimates are based on data reflecting levels of development dating back as far as the 1960s. A partial update to these damage functions was done in 2004, but was incomplete. A significant effort is needed to update these discharge-damage functions based on current levels of development to more accurately estimate damages prevented by SWF projects. Lost Gate Receipts: While the damages prevented by SWF projects are an important service to the Nation, the flooding experienced in the Distinct during the period from March to July 2007 caused significant reductions in attendance to recreational facilities at SWF projects due to park closures. These closures resulted in substantial losses to the Treasury in terms of lost revenue from foregone gate receipts. In some cases, refunds on deposits for facility reservations had to be made because facilities were unavailable due to closures or damage to facilities. Totals of lost receipts can be found on the summary spreadsheet at the end of this report. Damages to SWF Prime Facilities and Recreation Infrastructure: An additional consideration in assessing the impacts of this series of events is the cost to the federal government to repair SWF prime facilities, such as embankments, spillways, outlet channels, and floodgates. Most SWF projects sustained considerable damage to recreation facilities and infrastructure in the performance of their flood control function, including direct damages to recreational facilities such as restrooms, gatehouses and shelters, massive amounts of floodwater debris along project shorelines, badly damaged roads and culverts, and reduced revenue due to park closures. Delays in adequate funding of debris removal and repair of recreation facilities and infrastructure forced closure or limited public access to parks and recreational areas which are in high demand by the public. Current estimates for repairs to prime facilities total $16.55 million. Current estimates for repairs to recreational infrastructure total $30.10 million, for a total of $46.65 million. A breakdown of these estimates is shown in Tables 2 and 3. Fort Worth District Dams and Lakes 1199

6 Table 2. Prime Facilities Critical Infrastructure Damage Estimates Due to 2007 Flooding Event Project Dam Safety Issue Proposed Repair Proctor Lake* Bardwell Lake Ray Roberts Lake Belton Lake Extensive seepage associated with permeable soils layers under the main embankment Skin slides along 1,400 linear feet of downstream embankment Instability of riprap along outlet works and discharge channel during full open release. Possible instability of hydraulic jump at full open release Instability of riprap along outlet works discharge channel at Engineering study of seepage mapping results and design to prepare plans and specifications for permanent repair Lime stabilization of embankment at slide locations Addition of riprap to provide for protection of side slopes at stilling basin and discharge channel. Hydraulic analysis of flow characteristics to determine tailwater and effects on hydraulic jump Estimated Cost ($1,000s) 11,300 1,500 1,250 Addition of riprap to provide for protection of side slopes at stilling basin and discharge channel 2,500 full release * Proctor Lake received $800K in emergency funding in fiscal year 2007 for construction of an engineered access road along the downstream toe to allow stable vehicle access, filtering of seepage and geophysical mapping of seepage. Total 16, Collaborative Management of Integrated Watersheds

7 Table 3. Recreation Infrastructure Damage Estimates Due to 2007 Flooding Event Project Flood Damages Estimated Repair Cost ($1,000s) Bardwell Lake Flood debris removal; road repair; park facility repair 1,200 Belton Lake Flood debris removal; park facility repair; 90% facilities inundated 2,500 Benbrook Lake Flood debris removal; road repair; park facility repair 1,050 Canyon Lake Flood debris removal; road repair 500 Lake o the Pines Road repair; park facility repair 550 Granger Lake Flood debris removal; park facility repair 950 Grapevine Lake Flood debris removal; park facility repair; road repair; shoreline erosion 2,250 Lavon Lake Flood debris removal; park facility repair; road repair; shoreline erosion 1,650 Lewisville Lake Flood debris removal; park facility repair; road repair; shoreline erosion 2,250 Navarro Mills Lake Flood debris removal; park facility repair; road repair; shoreline erosion 1,050 Lake Georgetown Flood debris removal; park facility repair; 50% facilities inundated 2,250 Proctor Lake Flood debris removal; park facility repair; road repair 3,000 Somerville Lake Flood debris removal; park facility repair; shoreline erosion 1,250 Stillhouse Hollow Flood debris removal; park facility repair; Lake 98% facilities inundated 4,000 Waco Lake Flood debris removal; road repair; park facility repair 2,500 Whitney Lake Flood debris removal; road repair; park facility repair 2,500 Wright Patman Road repair; park facility repair Lake 650 Total 30,100 Impacts to the Local Economy Impacts are felt not only at SWF recreational facilities, but also on the local economy since visits also generate economic activity to surrounding businesses. Reductions in attendance are comparable to those experienced in gate receipts. Using the Recreation Economic Assessment System (REAS) developed by the Engineer Research and Development Center (ERDC), an estimate for the average amount spent per visit was derived based on national average spending patterns. The REAS model estimates that the average amount to be spent per visit SWF-wide is $ Table 4 depicts the difference Fort Worth District Dams and Lakes 1201

8 in attendance for the April to July 2007 time period (those months showing declines) compared to the same period in Multiplying the average amount spent by this decrease in attendance generates an estimate of the potential impact these storm events had on the local economy. As shown, the potential impact for the period totals $47.26 million. While this estimate may be inflated in that it may not take into account discretionary spending that may occur at other recreational outlets when facilities at SWF projects are not available, it does show that the closure of SWF facilities has significant impacts to the local economy. Table 4. Difference in Attendance for April-July 2007 Compared to Same Period in 2006 Date Attendance Decline Per Visit Local Economic From 2006 Spending Impact April ,750 $ $7,568,828 May ,483 $ $4,929,336 June ,933 $ $7,417,412 July ,411,737 $ $27,345,346 Total -2,439,903 $ $47,260,921 Reservoir Control ACTIONS TAKEN The most severe flooding happened in three major river basins: Trinity, Brazos, and Colorado. Due to the magnitude of flooding on 1 July, state emergency operations personnel requested that the SWF provide them a press release each day on status and forecasts for our lakes and the flood situation. Reservoir Control Section in the SWF Office went into a 24-hour operation the same day. Trinity River: Prior to the heavy rains, the lakes in the Elm Fork were 6 to 12 feet below their conservation pool levels. Inflows into the reservoirs in the Trinity River in March were minor due to the dry soil conditions. The most dramatic rainfall fell on March 29 in the Richland-Chambers Creek watershed where 6.5 inches was recorded, producing a peak inflow of 51,000 cfs into Navarro Mills Lake, which rose 10 feet on 30 March and rose another 3 feet in the next 3 days. The nearby watershed above Bardwell Lake received similar rainfall, which raised the lake level 10 feet in two days. The rains in late May produced moderate inflows. Lewisville and Grapevine Lakes rose into their flood pools for the first time in over two years. The June 17 flood event in north Texas produced a peak inflow into Ray Roberts Lake of 136,000 cfs, which raised the lake about 4 feet into the flood pool. The observed peak flow on the Elm Fork at the Carrollton gauge from this storm was less than 7,000 cfs. However, without the three flood control projects in the Elm Fork watershed, the peak flow would have been about 173,000 cfs. The Dallas gauge on the Trinity River recorded a peak flow of 16,800 cfs. Without the five upstream SWF projects the peak flow 1202 Collaborative Management of Integrated Watersheds

9 through Dallas would have been 127,000 cfs. A chart detailing the regulated flows through Dallas is presented in Figure 3. The high inflows from the June flood event sent Ray Roberts and Lewisville Lakes into their surcharge pools on July 1. This was the second time that Ray Roberts Lake has occupied its surcharge pool. Since Ray Roberts Dam was constructed with its spillway perched 5 feet above the top of the flood pool, the flood gates had to be opened to release surcharge water. This discharge was passed downstream to Lewisville Lake, and contributed to the overtopping of the Lewisville spillway. This event marks the sixth time that the spillway at Lewisville Dam has overflowed in the 52 years of its operation. The spillway at Lewisville Dam was designed to have a 35-year frequency for overtopping. Even though lakes on the Trinity remained very high, flood releases had to be delayed to allow the high flows on the main stem of the Trinity River to recede below flood stage (except at Ray Roberts and Lewisville which were in their surcharge pool). The unopened lakes continued to rise. Ray Roberts Lake peaked at elevation feet and was in the surcharge pool for 14 consecutive days. The flow over the spillway at Lewisville Dam increased until the lake peaked at elevation feet on July 7. Since the Elm Fork downstream had sufficiently receded, flood releases were initiated through the flood gates the following day. Spillway and flood gate discharges were made simultaneously to lower the lakes as quickly as possible. Water was flowing over the Lewisville spillway for 21 days. Brazos River: In early March, most the lakes in the Brazos River were below their conservation pools. The rains in mid-march saturated the soil over a wide region around the Waco area. Many streams and creeks that had been dry for over a year began to flow. Fort Worth District Dams and Lakes 1203

10 140, , ,000 80,000 60,000 40,000 20,000 0 Trinity River at Dallas, TX June July Natural Flow Observed Flow Control Point Flow Flow (CFS) Flow = 13,000cf Natural Peak Flow = 126,776cfs Natural Peak Flow = 110,782cfs Observed Peak Flow = 37,500cfs Observed Peak Flow = 16,800cfs Figure 3. Chart Detailing Regulated Flows through Dallas Floodway 1204 Collaborative Management of Integrated Watersheds

11 The heavy rain that fell on March 29 was centered over Aquilla Lake where over 7 inches fell. The heavy rainfall pattern crossed the main stem of the Brazos River and extended across the Bosque River and over into the Leon River. Aquilla, Whitney, Waco, Belton, and Stillhouse Hollow Lakes all had high inflows and filled into their flood pools as a result of this storm event. In the Brazos River, the high releases from Possum Kingdom Lake raised Whitney Lake to elevation feet, which is feet above the top of the conservation pool. The high lake level forced the temporary closing of several bridges at the upper end of Whitney Lake. By regulating the combined discharges from Whitney, Waco and Aquilla Lakes, the flows through the city of Waco were held at approximately 30,000 cfs. Absent this regulated discharge, the flow through the city of Waco would have been about 110,000 cfs. As the flood wave traveled down the Brazos River, the observed peak flow at Hempstead was 69,100 cfs, where the controlled flow is 60,000 cfs. Had it not been for the nine SWF lakes in the Brazos River, the flow at Hempstead would have been over 187,000 cfs. On the Little River system, a tributary of the Brazos River, the intense rains of June sent a flood wave down the Leon River and into Proctor and Belton Lakes. Proctor Lake was about six feet above the top of the conservation pool before this event. The resulting flood wave had a peak inflow of 34,000 cfs into the lake, which raised it another 25 feet to a peak elevation of feet, which is the second highest recorded level. Due to the resulting high volume of seepage through the embankment at Proctor Dam, a deviation was requested and approved to increase the release from the allowable 2,000 cfs to 4,000 cfs. The increased discharge did not cause significant damages or generate complaints from downstream property owners. Belton Lake was about 13 feet above the top of the conservation pool before the intense rains fell. The ensuing flood wave had a peak inflow to Belton Lake of 43,000 cfs that raised the lake another 27 feet to a peak elevation of feet, just 1.36 feet short of going over the spillway. Belton Lake was forecast to remain in the flood pool well into October. The total inflow volume into Belton Lake from March through July was almost 1.5 million acre-feet, enough to fill the flood pool two and a half times. The observed flow at the USGS gauge on the Little River at Cameron was 35,900 cfs. If not for the five SWF lakes in the Little River, the peak flow would have about 102,600 cfs. Colorado River: On January 1, 2007, Lake Travis (Marshall Ford Dam) was at elevation feet, which is 37 feet below the top of the conservation pool. Spring rains in the Colorado Basin filled the lake s conservation pool, feet, on May 27. A dramatic rise came a month later after the Marble Falls flood event. Between 27 June and July 13, Lake Travis had a computed inflow volume of a little over 1,000,000 acre-feet, with a peak inflow of approximately 240,000 cfs. To prevent damages in the city of Austin, the control flow is 30,000 cfs. The flood gates were opened on the 27 June to release 26,000 cfs, but the lake continued to rise for the next seven days. Even with the releases, Lake Travis reached a peak elevation of feet on July 5, with a rise totally feet in The flood gates remained opened for 21 days consecutive days, until they were closed on July 19. In this time period, the Colorado River had flow of at least 25,000 cfs Fort Worth District Dams and Lakes 1205

12 in its entire length from Marshall Ford Dam to Matagorda Bay. The high flow interrupted barge traffic in the Intercoastal Waterway. Red River: After an extreme drawdown caused by a two-year drought in the local area, the watershed above Cooper Dam and Jim Chapman Lake received above-average rainfall during the month of July. As a result, Jim Chapman Lake rose into the flood pool for the first time in 4 years. No unusual reservoir regulation or discharges were required for management of this lake. Emergency Management In response to the serious flooding in many parts of Texas, on June 27 the Emergency Management (EM) Office created an event in ENGLink titled 27 June Storms and Flooding, standard procedure during or after a disaster event. Situation Reports and maps were created and released by the EM Office for upward reporting. Additional actions taken by the EM Office included the following: The SWF EM Office participated in Texas State Operations Center (SOC) teleconferences as often as twice daily. Under the authority of Public Law (PL) 84-99, EM was also postured to meet any requests for assistance from state or local authorities. June 27: FEMA Region VI Regional Response Coordination Center (RRCC) remained activated at Level 3 while monitoring the situation. A SWF predesignated Liaison Officer (LNO) was deployed to the Texas SOC in Austin on June 30, where he remained until released on 5 July. July 1: The SWF EM office requested $100,000 of Code 210 (Response Operations) funds to support ongoing flood response operations. Funds were received on July 2. July 2: the Regional Liaison Officer (RLO) for Tarrant County contacted the SWF EM Office to relay a request for sandbags from the City of Flower Mound. The city received 1,000 sandbags at 1400 hours on July 2. July 4: the City of Watauga submitted a request for sandbags. Tarrant County EM Office EM coordinated with SWF EM to provide sandbags on July 5. July 9: the SOC began conducting recovery coordination calls on Mondays, Wednesdays and Fridays. SWF EM was prepared to participate on an as-needed basis. July 20: SWF received a request for assistance under PL to repair Leonard Park Levee in Gainesville, TX. This non-federal project is an active participant in the SWF Rehabilitation and Inspection Program (RIP). The SWF EM requested $20,000 to initiate the field investigation phase to produce the Project Information 1206 Collaborative Management of Integrated Watersheds

13 Report (PIR). The PIR will then be submitted to HQUSACE with a construction funding request to repair the levee damage. July 20: SWF requested and received $800,000 of Class 200 funds to perform investigations and preliminary repairs to increased seepage problems at Proctor Lake, caused by extremely high flood pool storage. August 8: SWF received a request for assistance from Laredo regarding the Zacate Creek Channel Improvement Project (CIP). The City of Laredo requested rehabilitation assistance under PL SWF EM requested $20,000 to initiate the field investigation phase to produce the Project Information Report (PIR). SWF EM conducted a site visit with the City of Laredo and SWF Operations Division to assess the damage and determine eligibility for PL assistance. Dam Safety Program The following actions are Standard Operating Procedure (SOP) for flood events such as those which occurred in March through June 2007: The Dam Safety Program Manager (DSPM) shall closely monitor the pool elevations of all the lakes being affected by the flood events, review the corresponding Emergency Action Plans (EAPs), and advise the Operations Project Managers (OPMs), especially those with impacted lakes in their respective clusters. Lake personnel shall conduct weekly, daily or 24-hour surveillance of those dams and appurtenant structures in accordance with the threshold pool elevations indicated in the EAPs, and reports to the DSPM in a timely manner. SWF Geotechnical personnel and lake personnel shall monitor instrumentation (piezometers, seepage weirs, etc.) weekly, daily or at more frequent intervals depending on the situation being monitored. Piezometers from 9 of the 25 lakes are monitored by SWF Geotechnical personnel and the rest by lake personnel. The following actions were taken by the SWF Dam Safety Program personnel: The DSPM monitored the pool elevations of all the lakes being affected by the flood events and reviewed the corresponding EAPs. Based on the EAP review, a spreadsheet (Special Inspection Schedule Based on Pool Elevations) was created to monitor the pool elevations of the 25 dams in the SWF on a daily or fraction of a day basis. Additionally, the spreadsheet contained some pertinent elevation data of the dams such as top of dam, spillway crest, flood control pool, and conservation pool; and also contained color-coded threshold elevations indicating those lakes that required weekly, daily and 24-hour inspections. An example is shown in Figure 4. Fort Worth District Dams and Lakes 1207

14 Figure 4. Special Inspection Schedule Based on Pool Elevations 1208 Collaborative Management of Integrated Watersheds

15 The spreadsheet was updated 2-4 times a day during the most critical periods of the flooding event (late June and early July) and twice daily until the third week of July. It is still being and will be updated until all lakes drop below the threshold pool elevations for weekly inspections. Updated spreadsheets were continuously sent to those OPMs with impacted lakes in their respective portfolios. Lake personnel did an excellent job conducting the threshold inspections as recommended in the EAPs and as shown in the spreadsheet. Reports on the inspections and instrumentation data were sent to the DSPM in a timely manner. At the peak of the flood event (July 8-10), there were 14 lakes with at least weekly inspections of which eight were on daily inspections and four on 24-hour surveillance. The spreadsheet of the peak is attached for illustration. SWF Geotechnical personnel monitored piezometers weekly and biweekly at 6 of the 9 lakes that fall under their responsibility. These lakes were Lewisville, Ray Roberts, Waco, Georgetown, Granger and Stillhouse Hollow. Public Affairs Office For the Public Affairs Office (PAO), this flood event was comparable to that of the 1992 event in terms of media and public interest. PAO had to provide real time information and immediate response to keep the public informed. During the flood event, PAO prepared news releases for statewide release to all print and electronic media in order to disseminate updates on the situation. Inquiries from the media and the public were nearly continuous during much of the event. In addition to handling general queries, the Public Affairs Office organized two media events to address specific regional flooding concerns. The first was held in the SWF office on July 3, and provided information on the operation of SWF lakes and levees in the North Central Texas area. A 15-minute briefing was presented. In attendance were the Fort Worth Star-Telegram, NBC Channel 5, Univision (Spanish television affiliate), Dallas Morning News, KTVT Channel 11, WFAA Channel 8, KRLD Radio, CW Channel 33, Sanger Courier, Pilot Point Post Signal, and WBAP Talk Radio. After the briefing, media were escorted into the Reservoir Control office for demonstrations and interviews. The second event was held at Proctor Lake on July 17 to dispel rumors and provide an update on the flooding situation and seepage issues at the dam. Proctor Lake experienced its second-highest pool of record for the lake since its construction in A 30-minute briefing on lake operations and dam safety was presented, followed by an opportunity for media representatives to view the seepage area and corrective actions taken at the toe of the dam. Covering the event were Dublin Citizen, De Leon Free Press, Empire Tribune, Brownwood Bulletin, Comanche Chief, and the Abilene Reporter News. Fort Worth District Dams and Lakes 1209

16 EVALUATIONS Reservoir Operations What went well: At Proctor Dam, the high pool level caused seepage through the embankment. Multiple sand boils appeared and threat of piping became a major concern. To ensure the integrity of the dam, a deviation to the plan of regulation was approved to allow higher releases to more quickly evacuate the flood water. Seepage was remediated temporarily, but a permanent repair is required. Normal maximum controlled release from Proctor Lake is 2,000 cfs. In order to achieve a 4000 cfs release, it was necessary to establish a coordinated communication line with landowners, county judges, emergency managers, in the three downstream counties. Due to this new coordination procedure, it is now possible to make releases from Proctor Lake up to 4,000 cfs without significant downstream damages. In the Little River basin, normal control discharge for the Little River at Cameron is 10,000 cfs. We regulated up to 20,000 cfs at the control when lake levels upstream approached spillway levels. No complaints were recorded. Previous field observations of historical floods were used in making the decision to increase the control discharge. Periodically exceeding the normal discharge control helped keep Belton and Stillhouse Hollow Lakes from going over their spillways. At Whitney Dam, releases were calculated to permit continuous water flow through the turbines. This permitted the electrical generator to run at full capacity 24 hours per day for 106 consecutive days, producing 76,638 megawatt hours of power during that period. Lessons Learned: Although all the SWF projects performed well during this event, the following problems, issues and needs arose or were revealed during reservoir operations. The lake level at Ray Roberts Dam rose above the flood pool and into the surcharge pool and surcharge releases were initiated. Testing the flood gates revealed that the gates should be opened at a slower rate to allow a higher tailwater to develop. The water control manual will be revised to reflect the need for the slower opening of the flood gates. Additional riprap protection must be added at the outlet works stilling basin and discharge channel to protect the banks during maximum discharges. Prior to the substantial rainfalls in north Texas during 2007, the region experienced a significant drought. Drought followed by heavy rains exacerbated conditions that resulted in multiple skin slides on the embankment at Bardwell Dam. Left unrepaired, the skin slides have the potential to threaten the integrity of the embankment by migrating to the crest. During regulated releases, movement of the riprap along the top of the discharge channel downstream of the stilling basin of Belton Dam was noticed by project personnel. Bedding material has washed out beneath the riprap and portions of the stone protection are being held in place by bridging action of interlocked pieces of riprap. Releases were 1210 Collaborative Management of Integrated Watersheds

17 reduced through the outlet works to minimize the damage to the discharge channel, but additional damage to the riprap is expected. Project personnel continue to monitor the condition of the riprap and coordinate release rates with Reservoir Control in the SWF office. Similar field observations for the Trinity River at Rosser along the Dallas Floodway were used to increase the control there from 15,000 cfs to 20,000 cfs. No downstream complaints were received. There is a need to train at least two more people from Hydrology & Hydraulics Section to back up permanent staff in real time flood forecasting and regulating the lakes in a major flood. Damages to SWF Prime Facilities and Recreation Infrastructure What went well: Most of the SWF prime facilities performed as they were designed to. The SWF has for many years made it a best management practice in the operation, maintenance and replacement of its recreation facilities and infrastructure to make its facilities as flood resistant as practicable. Strategies such as locating facilities at reasonably higher elevations or hardening them in place have been successful in reducing damages sustained in minor floodwater retentions. In an event of this magnitude, however, considerable infrastructure damage must be expected. SWF lake staffs performed efficiently and effectively in evacuating park visitors, securing parks and closing roadways during sudden pool rises, which often occurred with little warning. Lessons Learned: Existing needs for repairs to prime facilities that had not been accomplished due to lack of funding were underlined by high pool levels and flood release requirements. Additionally, maintenance items which had not previously been identified surfaced during operations during the severe flooding. Unfortunately, when critical maintenance items become apparent, the budget cycle does not provide funding for two fiscal years from the current year. When the repair required is critical to the safety of the dam, project offices may or may not have sufficient funding on site to pay for the maintenance work. Supplemental funding is critical to ensure continued operation and integrity of the project prime facilities. Delays to adequate funding of needed repairs to prime facilities have the potential to create or intensify serious dam safety deficiencies at SWF lake projects. Emergency Management What went well: EM personnel did an exceptional job in responding to requests from the Governor's Division of Emergency Management for assistance during this flood event. Coordination between State Disaster District Committee Chairman (DDC), Regional Liaison Officers (RLOs), and EM was outstanding in providing sandbags to Denton and Tarrant Counties. Fort Worth District Dams and Lakes 1211

18 EM s 24/7 emergency contact number proved invaluable in receiving and responding to requests for assistance from State and local governments. EM was totally accessible to state and local government. Lessons Learned: Coordination between EM and other SWF elements was slow to develop during the event. Incidents or occurrences reportable under the Commander s Critical Incident Report policy need to be reported to EM as soon as possible, regardless of what other notifications may have been made. Dam Safety Program What went well: The DSPM made several site visits to Proctor, Lewisville and Ray Roberts to assess issues that occurred during the critical time period of the flood event. Proctor had the most critical situation with a seepage that developed on a 1,000-foot reach along the toe of the embankment on the left side of the spillway. A monumental team effort that included sand-bagging, increasing water releases, fast-track contracting to build an access road, and conducting a seepage mapping, plus a media event to inform the public was required to take care of Proctor, and all occurred in the month of July. Considerable attention was given to the Federally-funded Dallas Floodway and Levees components. City personnel were proactive, inventive and utilized all available resources to inspect their project. City personnel asked questions and responded immediately to suggestions made by SWF officials. The DSPM and the entire Dam Safety/Geotechnical team were continuously active during the entire flood event, interacting with the field via and telephone conversations and providing recommendations as needed. Lessons Learned: The maintenance deferred for lack of funds at some of the projects, especially the embankments, slowed down the response, made the inspections more difficult, increased safety hazards, and made it more difficult to find the instruments. Embankments and all areas of contacts between embankments and abutments or structures should be well maintained more consistently throughout the year and not only prior to scheduled inspections. Instrumentation should be monitored by the same personnel in order to maintain consistency in the readings. As an option, several employees should be trained to perform this activity. Instrumentation should be read periodically (not only during a flood event) as scheduled and sent immediately to the Dam Safety team. Some lakes are not sending the data to the SWF consistently throughout the year as scheduled. Deficiencies found during these extreme events should be well documented, located by GPS, and photographed for correlation with future events. Photos of observations should be taken both from a macro and a micro perspective and sent immediately to the DSPM for interpretation and discussion. Reports from weekly, daily and 24-hour inspections should be sent in an attachment on separate s. Some lakes sent information in the body of the s instead of sending the report as an attachment on a template specially made for that lake Collaborative Management of Integrated Watersheds

19 sequencing or strings should be avoided unless a specific issue is being discussed. Some of the inspection reports were sent in chains, which makes filing and follow-up more difficult. The use of telephone communication should be used more often to report relevant and highly critical issues. is fine but sometimes it needs to be reinforced with a telephone call. Aerial photographs should be taken of all the lakes affected by a flood event of this magnitude. This provides a better perspective of the areas that get flooded upstream of the dams. The project O&M manual (written in 1960) does not address appropriate emergency actions for handling shallow slides on the wet side of the levee during flood events. Although project personnel have extensive experience repairing such slides during dry conditions, the same rules do not apply during floods and/or when portions of the slide are underwater. The manual needs to be updated to provide guidance for this common failure mechanism. Public Affairs Office What went well: PAO personnel responded to all calls within hours. Field-level employees such as managers, park rangers and other lake staff were able to respond quickly and accurately to media calls. This was due to the media training they previously received from PAO. News articles resulting from the 250 media inquiries to PAO and the field offices were accurate and key messages were well stated. Subject matter experts were willing to respond every time they were asked, and many were called upon to do on-camera interviews. All interviews had positive outcomes. The SWF website became a valuable tool in communicating the current situation. Media and other callers were directed to the website, and once they had been walked through the site, were able to use the SWF pages to obtain information themselves. The media events were particularly successful; they were proactive and timely to the issues at hand, and the events enabled all interested media outlets to obtain the information they needed without having to chase the story themselves. These events allowed media representatives to meet with SWF officials face-to-face and tell the flooding story collectively with less chance of misquoting or misrepresenting the information. Reporters invited to such events view such opportunities as personable and try harder to produce a well-balanced story. Lessons Learned: In addition to the two media events that were held, it might have been beneficial to have had events at Waco, Lewisville, Canyon, and Belton/Stillhouse Lakes to help correct rumors and misinformation circulating in those areas. For purposes of documentation and of subsequently telling the USACE story, funding should be made available to procure professional still and video photography, including aerial footage. Some of the lake staffs were able to take on this added responsibility as a collateral duty, but the photo coverage of the event was sporadic. Fort Worth District Dams and Lakes 1213

20 Although SWF leadership was kept well apprised of the changing situation, the internal audience was not. Recommend that PAO work with Operations Division during future events to provide news reports to all employees. CONCLUSIONS The spring and early summer of 2007 was one of the wettest on record in South Central and North Central Texas. Persistent rains falling on saturated soils, punctuated by slowmoving storm cells which produced amazing rainfall totals, caused water surface elevations at 23 of the 25 SWF reservoirs to rise into their flood control pools, with two of these reservoirs actually exceeding their flood control capacity. Although some severe localized flooding occurred along Texas rivers and floodplains, SWF reservoirs performed as designed, and SWF team members worked in a coordinated and professional manner to meet the challenges of this series of events. In the performance of their flood control function from March to July 2007, SWF reservoir projects sustained estimated damages of $43.6 million to their prime facilities and recreational infrastructure. However, the operation of these same projects and associated floodways prevented an estimated total of $7.9 billion of flood damages in Texas. ACKNOWLEDGMENTS This paper is based on the After Action Report (AAR) prepared by a Project Delivery Team (PDT) of the USACE SWF in the aftermath of the flood events of The authors herein acknowledge the following PDT members, who contributed to the AAR: Allen Avance, Kevin Craig, William Fickel, Jodie Foster, Tim Gibson, Paul Krebs, Judy Marsicano, Larry Mendoza, Doug Perrin, Brian Phelps, John Rael, Lynn Rednour, Paul Rodman, Mike Velasquez, and Constance Williams. This paper could not have been possible without their valuable contributions Collaborative Management of Integrated Watersheds