About
About the Flood Control District
Flood Damage Reduction Tools
Structural Tools
Non-Structural Tools
Infrastructure Maintenance
Harris County's Flooding History
Hurricane Harvey
Spring Floods 2016
Hurricane Ike 2008
Tropical Storm Allison 2001
Flooding and Floodplains
Drainage Network
Benefits of Flood Damage Reduction
Partnership Funding
CDBG Funding
Activity
2018 Bond Program
Prioritization Framework
Project Lifecycle
2018 Bond Program FAQ
Completed Bond ID Summaries
Capital Improvement Program
Subdivision Drainage Projects
Maintenance Programs
Property Management Program
Abandoned Bridge Program
Vegetation Management
Tree Planting Program
Major Maintenance Projects
NRCS-HCFCD Partnership Repair Program
Emergency Repairs - COMPLETED
Additional Programs
Hurricane Harvey Disaster Recovery FEMA Sediment Removal Program
Development Coordination and Inspection
LOMR Review Program
MAAPnext Development Program
Property Acquisition Program
UAS and The Flood Control District
Watershed Environmental Baseline (W.E.B.) Program
Wetland Mitigation Banks
Stormwater Quality
Home Buyout Program
Floodplain Preservation
Raingarden Demonstration Project
Active Projects
Countywide or Multi-Watershed
Addicks Reservoir
Armand Bayou
Barker Reservoir
Brays Bayou
Buffalo Bayou
Carpenters Bayou
Cedar Bayou
Clear Creek
Cypress Creek
Greens Bayou
Halls Bayou
Hunting Bayou
Jackson Bayou
Little Cypress Creek
Luce Bayou
San Jacinto River
San Jacinto & Galveston Bay
Sims Bayou
Spring Creek
Spring Gully & Goose Creek
Vince Bayou
White Oak Bayou
Willow Creek
Resources
Storm Center
Flood Warning System
Report House Flooding
Preparing for a Storm
Interactive Mapping Tools
Harris County Flood Education
Mowing Schedule Explained
Active Construction Projects
BMPbase - Regional BMP Database
Model and Map Management (M3) System
Harris County Floodplain Reference Marks
Education Materials
Clean Waterways
Regional Public Education Services Program
School-Age information materials
Technical Manuals
All Technical Manuals
12 Month Bid Outlook
2019 Land Surveying Guidelines
Application to Discharge (2011)
2019 Atlas 14 Policy Criteria and Procedures Manual (PCPM)
Cad Standards Manual
Channel System - Unit Numbers
Construction Unit Pay Items (Quarterly) - Project Bidding
Design Guidelines for HCFCD Wet Bottom Detention Basins With Water Quality Features
Design Manual for Articulating Concrete Block Systems
Development Coordination and Inspection
Draft Hazard Mitigation Plan (2011)
Harris County Low Impact Development Design Criteria Manual
Hydrology and Hydraulics Guidance Manual
Little Cypress Creek Interim Guidelines
Little Cypress Creek Master Drainage Plan
Lomr Delegation
Model and Map Management System
Natural Stable Channel Design
Ordinary High Water Mark Manual
Previously Approved Submittals Reference Book
Quality Assurance / Quality Control
Standard Specifications & Related Drawings
Supplemental Guidelines and Criteria for Developing in the Addicks Reservoir Watershed, Barker Reservoir Watershed and the Cypress Creek Watershed Upstream of Us 290
Upper Langham Creek Development Guidelines
Watershed Coordination
Downloads
Glossary
FAQ
Community
Community Engagement and Public Meetings
Contact Us
General Inquiries
Service Request
Community Satisfaction Survey
Floodplain Administrators
Public Information Requests
Harris County Phone Directory
Sign Up for News
Speakers and Event Request
Community Services Program
Press Room
Press Room
The Watermark Newsletter
Media Requests
Contact Our Communications Team
Work With Us
About  ⁄  Flood Damage Reduction Tools  ⁄  Structural Tools

Structural Tools

Structural Tools
Menu
About the Flood Control District
Flood Damage Reduction Tools
Harris County's Flooding History
Flooding and Floodplains
Partnership Funding

Flood Damage Reduction Tools - Structural

Channel Modifications

Photo: Widening of Sims Bayou

Also known as channel conveyance improvements, channel modifications are man-made changes to a channel's characteristics, typically for the purposes of reducing flood damages by increasing its overall conveyance capacity. This can be accomplished by widening and/or deepening the channel, reducing the friction by removing woody vegetation, or by occasionally adding concrete lining. It should be noted that only 6% of the channels in the county's drainage infrastructure inventory are concrete lined.

Stormwater Detention (Basin)

Photo: Rendering of Keith-Wiess Park showing flooding conditions and normal conditions

A stormwater detention basin is another structural tool used by the Flood Control District when implementing a project. A stormwater detention basin is a large, usually excavated area of land, frequently adjacent to a channel, which is designed to receive and hold above-normal stormwater volumes. The detained stormwater then slowly drains over time out of the detention basin as water surface elevations in the receiving channel recede.

Bypass Channel Construction

Photo: Jersey Village Bypass Channel

A bypass channel diverts excess stormwater "around" an area with restricted right-of-way or an area with sensitive environmental values. Bypass channel construction involves building a new channel that is attached to an existing channel and, as mentioned, conveying the excess stormwater runoff around its original path. Bypass channels usually "short circuit" the meander or curve of a bayou and are usually constructed in conjunction with downstream channel modifications or a detention basin.

Bridge Modification

Photo: CJ Tamborello Pedestrian Bridge

Bridge modification is another structural tool used in flood damage reduction. It involves the replacement, extension or modification of a bridge in order to remove an impediment to flow within a channel and/or accommodate channel modifications. It can also lessen the likelihood of debris snagging on the bridge piers.

Levee

Photo: Inverness Forest Levee, north Harris County

A levee is a physical barrier constructed to protect areas from rising floodwaters. Levees are not feasible in most cases in Harris County for a variety of important reasons. Levees typically remove valuable flood plain storage and block the ability of the channel to move water. There are also concerns with rainfall that falls within the levee itself. Most importantly is the possibility for catastrophic and sudden failure under extreme flood events, potentially resulting in loss of life and total destruction of property.