Presentation on theme: "Fort Bend Flood Management Association Flood Risk Reduction Symposium October 3rd, 2014 (Part-A) Brazos River at San Felipe - USGS Gage Fort Bend County."— Presentation transcript:
1 Fort Bend Flood Management Association Flood Risk Reduction Symposium October 3rd, (Part-A) Brazos River at San Felipe - USGS Gage Fort Bend County Levee Inspections Using USACE “RIP” StandardsFort Bend County Drainage District
2 BRAZOS RIVER FACTS: 1,280 Miles Long 45,575 Square Mile Drainage Area 19 Reservoirs4,000,000+ Acre-Feet of Flood Control Storage
3 Lower Brazos River Watershed USGS Flood Gages: HistoricalLower Brazos River Watershed USGS Flood Gages:Waco – Established 1899Richmond – Established 1922Hempstead – Established 1939Highbank – Established 1966Rosharon – Established 1967Bryan – Established 1994Fort Bend County Drainage District
4 Approximately 108 River Miles between Hempstead & Richmond gages. Contributing watershed increases by approximately 800,000 acres.FBCLID No. 20 and Pecan Grove MUD levees are located upstream of Richmond gage.Significant development occurring in northwest Fort Bend County.Previous Brazos River Flooding in Simonton / Valley Lodge AreaDec vs Oct Peak Elevations(Dec. 91) (Oct. 94)Hempstead:Interstate 10:F.M. 1093:F.M. 1489:Richmond:
6 USGS Brazos River at San Felipe Gage Located on the FM 1458 bridge near Stephen F. Austin State Park. This is the approximate mid-point between the Hempstead and Richmond gages.Installed by USGS field crews in September 2013.13 field measurements have been taken to date in order to establish a rating curve.Peak flow to date occurred onNov. 4, 2013 with a measured flowrate of 41,700 cfs.Funded to date by FBCDD, Gulf Coast Water Authority and USGS matching funds.
7 USGS Brazos River at San Felipe Gage The National Weather Service is planning to establish the San Felipe gage as a River Forecast site and create a website.They will provide 5-day forecasts based on available hydrologic, rainfall, and weather forecast data similar to the current data provided at other Brazos River gages.We are currently evaluating Fort Bend County historic data to establish flood warning stages and associated impacts.We are also working with Austin and Waller County officials to incorporate their potential flood impacts into the River Forecast website.
9 Fort Bend County Drainage District Levee Inspections using U.S. Army Corps of Engineers “Rehabilitation & Inspection Program” (RIP) Standards7 Major CategoriesInitial EligibilityGeneral Items for all Flood Reduction SystemsLevee EmbankmentsFloodwallsInterior Drainage SystemPump StationsFlood Damage Reduction ChannelsEach of these major categories is made up of specific inspection components called “Rated Items”.There are a total of 75 “Rated Items” evaluated during our inspections.Grades of “Acceptable”, “Minimally Acceptable” or “Unacceptable” are assigned to each of the 75 items.Fort Bend County Drainage District
10 Initial Eligibility (12 Rated Items) & General Items for Flood Damage Reduction Segments (3 Rated Items)These items are evaluated before the field inspections through a meeting with the District representatives.(Board Members, Engineer, Operator, Attorney)Updated contact lists, review history including dates of original construction and significant improvements, discuss jurisdictions (MUD’s, city limits, ETJ)Confirmation that the levee design meets current standards.(FEMA 44 CFR 65.10, FBCDCM Sec. 7.0)Evaluate emergency operation procedures and flood preparedness.Fort Bend County Drainage District
11 Levee Embankments – (15 Rated Items) Grass / SodEncroachmentsUnwanted Vegetation GrowthSlope StabilityErosion / Bank CavingSettlementDepressions / RuttingCrackingAnimal ControlToe Drainage SystemsFort Bend County Drainage District
12 Floodwalls – (9 Rated Items) TiltingSlidingSettlementFoundationsJointsConcrete SurfacesEncroachmentsUnwanted Vegetation GrowthToe Drainage SystemsFort Bend County Drainage District
13 Interior Drainage System – (15 Rated Items) Culverts / Discharge PipesSluice / Slide / Flap GatesConcrete SurfacesTilting/Sliding/Settlementor Undermining ofOutfall StructuresJointsInterior Flood Storage AreasOutfall ChannelsTrash RacksFort Bend County Drainage District
14 Pump Stations – (21 Rated Items) Maintenance, Training & Inspection RecordsPumpsGeneratorsPrimary and Backup Power SourcesFuel SystemIntake and Discharge PipesSluice / Slide / Flap GatesPlant BuildingsCommunication SystemTrash RacksFort Bend County Drainage District
15 2. Overall Project Rating Fort Bend County Drainage District “Interim Policy for Determining Eligibility Status of Flood Risk Management Projects for the Rehabilitation Program Pursuant to Public Law (P.L.) 84-99”U.S. Army Corps of Engineers – March 21, 2014Section 6.f.3 identifies 20 of the total 75 “Rated Items” that are specifically focused on to determine “Eligibility” for rehabilitation assistance.The levee system is eligible for rehabilitation assistance as long as they do not receive an “Unacceptable” rating on any of these 20 items.Two Separate Ratings are Issued:Eligibility Rating(Eligible or Ineligible)2. Overall Project Rating(Acceptable, Minimally Acceptable or Unacceptable)Fort Bend County Drainage District
16 Fort Bend County Drainage District Levee Inspections using U.S. Army Corps of Engineers “Rehabilitation & Inspection Program (RIP) StandardsInspections to Date:FBCLID No. 17 (Telfair)First Colony LID No. 2FBCLID No. 7 (New Territory)FBCLID No. 20Preliminary findings are issued to the District with final report issued 6 months later.Attempting to cover as many LID representatives as possible.USACE inspects Fort Bend County levees separately for their official RIP assessment.