Mansfield Dam and Lake Travis
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Corps of Engineers, Dept. of the Army, DoD § 208.19 § 208.19 Marshall Ford Dam and Res- conditions, the following upstream ervoir (Mansfield Dam and Lake U.S. Geological Survey gaging stations Travis), Colorado River, Tex. are used as indicators of the magnitude The Secretary of the Interior, of the inflows to Marshall Ford Res- through his agent, the Lower Colorado ervoir: River Authority (LCRA) shall operate (i) Colorado River near San Saba the Marshall Ford Dam and Reservoir (08147000). in the interest of flood control as fol- (ii) Pedernales River near Johnson lows: City (08153500). (a) Water Control Plan—(1) General ob- (iii) Llano River at Llano (08151500). jectives. The objectives of the Marshall (3) Standing instructions to dam tender. Ford Reservoir (Lake Travis) are the During normal conditions, the dam improvement of navigation, flood con- tender will regulate the project in ac- trol, stream regulation, generation of cordance with instructions received power, irrigation, water supply, and from the LCRA System Operator. Dur- recreation uses. ing flood conditions, when the Marshall (2) Overall plan for water control. Ford Reservoir level is within the flood Within the Colorado River Basin, four control zone, the LCRA System Oper- Federal projects provide flood control ator will regulate the project in ac- protection: Twin Buttes, O. C. Fisher, cordance with instructions received Hords Creek, Marshall Ford Reservoir. from the Corps of Engineers. In the The considerable distance (328 river event of a communication outage, the miles) and large intervening area LCRA System Operator will rely on the (19,990 square miles) separating Mar- Emergency Release Schedule, to make shall Ford Reservoir and the three changes in the rate of releases from the upper basin flood-control projects pre- lake. vent realizing any significant benefits (4) Flood control regulation—(i) Gen- from coordinating releases to control eral. At all times, releases shall be co- the inflow into Marshall Ford. Mar- ordinated such that the Colorado shall Ford Reservoir is the fifth project River, Texas, will be controlled when in a tandem of six lakes operated and possible, to remain below control controlled by the Lower Colorado River stages at downstream official U.S. Geo- Authority for the generation of hydro- logical Survey (USGS) gaging stations; electric power. These six projects in except that no curtailment of normal downstream order are: Lake Buchanan, hydroelectric turbine releases shall re- Lake Inks, Lake Lyndon B. Johnson sult thereby at any time. The USGS (Alvin Wirtz Dam), Lake Marble Falls river stations and their control stages (Max Starcke Dam), Marshall Ford are as follows: Reservoir (Lake Travis and Mansfield KEY DOWNSTREAM CONTROL POINTS Dam) and Lake Austin (Tom Miller Dam). The releases from each of the six Equivalent Control cubic feet projects are closely coordinated by the Station stage per second LCRA System Operation Control Cen- (feet) (c.f.s.) ter. Three of the projects (Lake Inks, Austin (08158000) ......................... 20.5 30,000 Lake Marble Falls, and Lake Austin) 1 24.8 1 50,000 are run-of-the-river projects. The Bastrop (08159200) ....................... 25.1 45,000 capabiity of the four upstream lakes to 1 26.7 1 50,000 control the inflow of flood water into Columbus (08161000) ................... 25.5 50,000 Marshall Ford depends on their ante- 1 Control stage when elevation 710 is forecast to be exceeded. cedent lake elevations. The majority of inflows to Marshall Ford are comprised Forecasted reservoir inflows and the of the mainstream flows of the Colo- upstream USGS gaging stations rado River, the tributary flows of the Pedernales River near Johnson City Llano River (entering the Colorado (08153500), Llano River at Llano River between Lakes Inks and Lyndon (08151500), and Colorado River near San B. Johnson) and the unregulated tribu- Saba (08147000) will be considered when tary flows of the Pedernales River (en- scheduling flood releases. tering between Lake Marble Falls and (ii) Flood control release schedule. Mar- Marshall Ford Reservoir). During flood shall Ford will be regulated to reduce 125 VerDate Mar<15>2010 08:18 Aug 02, 2012 Jkt 226134 PO 00000 Frm 00135 Fmt 8010 Sfmt 8010 Y:\SGML\226134.XXX 226134 emcdonald on DSK67QTVN1PROD with CFR § 208.19 33 CFR Ch. II (7–1–12 Edition) flooding on the Colorado River below trol stages on the Colorado River as the dam. This plan of regulation will specified in paragraph (a)(4)(i) of this govern flood control releases from Mar- section. These release rates will be shall Ford Dam as follows: maintained until the reservoir level (A) Elevation 681–683. If the reservoir falls below elevation 685 feet, m.s.l. level is forecast to rise above elevation (D) Elevation 691–710. Should the res- 681 feet, m.s.l. (top of conservation ervoir elevation be forecast to exceed pool) but not to exceed elevation 683 691 feet, m.s.l. (the top of the joint use feet, m.s.l., the releases shall be in- pool) but not to exceed elevation 710 creased to 3,000 c.f.s. and maintained feet, m.s.l: Releases will be made at until the reservoir level recedes to ele- 30,000 c.f.s. from the project or at a rate vation 681 feet, m.s.l. These release such that, when combined with local rates may need to be reduced due to ex- inflows below the dam, will equal but cessive downstream runoff to prevent not exceed downstream control stages exceeding the control stages specified on the Colorado River as specified in in paragraph (a)(4)(i) of this section. paragraph (a)(4)(i) of this section. (B) Elevation 683–685. If the reservoir These release rates will be so con- elevation is forecast to rise above ele- trolled until the reservoir level falls vation 683 feet, m.s.l. but not to exceed below elevation 691 feet, m.s.l. elevation 685 the releases shall be in- (E) Elevation 710–714. If the reservoir creased to 5,000 c.f.s. and maintained level is forecast to exceed 710 feet, until the reservoir level recedes below m.s.l. but not to exceed elevation 714 683 feet, m.s.l. These release rates may feet, m.s.l: Releases will be made at need to be reduced due to excessive 50,000 c.f.s. from the project or at a rate downstream runoff to prevent exceed- such that, when combined with local ing the control stages specified in para- inflows below the dam, will equal but graph (a)(4)(i) of this section. (C) Elevation 685–691. Seasonal. (1) not exceed the downstream control During the months of January through stages on the Colorado River as speci- April, July through August, and No- fied in paragraph (a)(4)(i) of this sec- vember through December: If the res- tion. These release rates will be main- ervoir elevation is forecast to rise tained until the reservoir level falls above elevation 685 feet, m.s.l. but not below elevation 710 feet, m.s.l. to exceed elevation 691, the releases (F) Elevation 714–722. If the reservoir shall be increased to 5,000 c.f.s. and level is forecast to exceed 714 feet, maintained until the reservoir level re- m.s.l. but not to exceed 722 feet, m.s.l: cedes below 683 feet, m.s.l. These re- Releases will be made at 90,000 c.f.s. lease rates may need to be reduced due from the project. Releases shall not ex- to excessive downstream runoff to pre- ceed the associated peak flood res- vent exceeding the control stages spec- ervoir inflow. ified in paragraph (a)(4)(i) of this sec- (G) Elevation 722 and above. If the res- tion. ervoir level is forecast to exceed ele- (2) During the months of May, June, vation 722 feet, m.s.l., the Bureau of September, and October: Should the Reclamation will schedule releases as reservoir elevation be forecast to ex- required for the safety of the structure. ceed 685 feet, m.s.l. but not to exceed (iii) Normal flood control regulation elevation 691 feet, m.s.l: Releases will schedule. The following table, Flood be made at 30,000 c.f.s. from the project Control Regulation Schedule, summa- or at a rate such that, when combined rizes the flood control releases sched- with local inflows below the dam, will ule for given reservoir levels and river equal but not exceed downstream con- conditions: MARSHALL FORD DAM AND RESERVOIR NORMAL FLOOD CONTROL REGULATION SCHEDULE Condition Reservoir level Flood control release Control points Pool Rising ........... Forecast: 681–683 1 ............................. 3,000 c.f.s .................. 30,000 c.f.s. (20.5 ft.) at Austin. 45,000 c.f.s. (25.1 ft.) at Bastrop. 50,000 c.f.s. (25.5 ft.) at Columbus. Do .................. Forecast: 683–685 ................................ 5,000 c.f.s .................. 30,000 c.f.s. (20.5 ft.) at Austin. 45,000 c.f.s. (25.1 ft.) at Bastrop. 50,000 c.f.s. (25.5 ft.) at Columbus. 126 VerDate Mar<15>2010 08:18 Aug 02, 2012 Jkt 226134 PO 00000 Frm 00136 Fmt 8010 Sfmt 8010 Y:\SGML\226134.XXX 226134 emcdonald on DSK67QTVN1PROD with CFR Corps of Engineers, Dept. of the Army, DoD § 208.19 MARSHALL FORD DAM AND RESERVOIR NORMAL FLOOD CONTROL REGULATION SCHEDULE— Continued Condition Reservoir level Flood control release Control points Do .................. Forecast: 685–691:. (a) During January, February, March, 5,000 c.f.s .................. 30,000 c.f.s. (20.5 ft.) at Austin. April, July, August, November, De- cember.