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