fort bend flood management association flood risk reduction symposium october 3rd, 2014 (part-a)...
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Fort Bend Flood Management AssociationFlood Risk Reduction Symposium
October 3rd, 2014
(Part-A)Brazos River at San Felipe - USGS Gage
Fort Bend County Levee Inspections Using
USACE “RIP” Standards
Fort Bend County Drainage District
BRAZOS RIVER FACTS:
1,280 Miles Long45,575 Square Mile Drainage Area
19 Reservoirs4,000,000+ Acre-Feet of Flood Control Storage
Fort Bend County Drainage District
HistoricalLower Brazos River Watershed
USGS Flood Gages:
Waco – Established 1899
Richmond – Established 1922
Hempstead – Established 1939
Highbank – Established 1966
Rosharon – Established 1967
Bryan – Established 1994
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 Area
Dec. 1991 vs Oct. 1994 Peak Elevations (Dec. 91) (Oct. 94)
Hempstead: 160.90 159.48Interstate 10: 113.40 115.50F.M. 1093: 107.00 107.70F.M. 1489: 101.40 102.30Richmond: 77.63 77.10
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 on Nov. 4, 2013 with a measured
flowrate of 41,700 cfs.
Funded to date by FBCDD, Gulf Coast Water Authority and USGS
matching funds.
USGS Brazos River at San Felipe GageThe 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.
USGS Brazos River at San Felipe Gage
USGS Link: http://waterdata.usgs.gov/tx/nwis/uv?site_no=08111850
www.fortbendcountytx.gov/riverlevels
Fort Bend County Drainage District
Fort Bend County Drainage District Levee Inspections using U.S. Army Corps of Engineers “Rehabilitation &
Inspection Program” (RIP) Standards
7 Major Categories1. Initial Eligibility2. General Items for all Flood Reduction Systems3. Levee Embankments4. Floodwalls5. Interior Drainage System6. Pump Stations7. Flood Damage Reduction Channels
Each 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
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
Levee Embankments – (15 Rated Items)Grass / Sod
Encroachments
Unwanted Vegetation Growth
Slope Stability
Erosion / Bank Caving
Settlement
Depressions / Rutting
Cracking
Animal Control
Toe Drainage Systems
Fort Bend County Drainage District
Floodwalls – (9 Rated Items)
Tilting
Sliding
Settlement
Foundations
Joints
Concrete Surfaces
Encroachments
Unwanted Vegetation Growth
Toe Drainage Systems
Fort Bend County Drainage District
Interior Drainage System – (15 Rated Items)
Culverts / Discharge Pipes
Sluice / Slide / Flap Gates
Concrete Surfaces
Tilting/Sliding/Settlementor Undermining of Outfall Structures
Joints
Interior Flood Storage Areas
Outfall Channels
Trash Racks
Fort Bend County Drainage District
Pump Stations – (21 Rated Items)
Maintenance, Training & Inspection Records
Pumps
Generators
Primary and Backup Power Sources
Fuel System
Intake and Discharge Pipes
Sluice / Slide / Flap Gates
Plant Buildings
Communication System
Trash Racks
“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, 2014
Section 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:
1. Eligibility Rating (Eligible or Ineligible)
2. Overall Project Rating(Acceptable, Minimally Acceptable or Unacceptable)
Fort Bend County Drainage District
Inspections to Date:
FBCLID No. 17 (Telfair)First Colony LID No. 2
FBCLID No. 7 (New Territory)FBCLID No. 20
Preliminary 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.
Fort Bend County Drainage District Levee Inspections using U.S. Army Corps of Engineers “Rehabilitation &
Inspection Program (RIP) Standards