Guide to Lake Houston Area Floodplain Regulations
Guidelines for floodplain development can bewilder even professionals. Overlapping jurisdictions often have different guidelines. And guidelines often change, as Houston’s just did. Houston now manages the 100-year and 500-year floodplains differently. Cities also have building codes that include more requirements.
People ARE generally allowed to build and place fill in floodplains. However, they must follow local floodplain guidelines and obtain permits that restrict what they can do. They must also submit environmental surveys, mitigate wetlands, and provide hydrologic and hydraulic studies. In Houston, they may move earth from one location to another within a floodplain, but not add to the total volume. The general rule of thumb: zero negative impact on the conveyance of the river.
If a development destroys wetlands, wetland credits must be purchased from a mitigation bank. Mitigation banks place conservation easements on some of our most valuable wetlands. By helping to finance conservation of those areas, destruction of less valuable wetlands elsewhere may be permitted. Generally but not always, the mitigation credits must be within the same watershed. However, this is not always the case. Extenuating circumstances may exist.
KSA once considered placing East End Park in a mitigation bank as a way to help finance its long range parks plan. The conservation easement would ensure that the character of the park never changed. And the money raised would have provided needed improvements to other parks at no cost to residents.
Federal Guidelines and How They Relate to Local
FEMA establishes minimum standards for a community to enroll in the National Flood Insurance Program (NFIP). By enrolling and administering floodplain regulations, it allows their residents the opportunity to purchase Flood Insurance through the NFIP. You must at least build at FEMA’s base flood elevation (BFE). But communities can and do set higher standards. And each may have different guidelines.
Engineers and regulators often talk about “freeboard factors.” Freeboard, a nautical term, means “the height of a ships side between the waterline and the deck.” In a flooding context, freeboard means minimum elevation above the BFE. You often see it described as “BFE + 1 ft.” Or 2 feet. Or X feet. Think of it as a safety margin. Any freeboard above the BFE is considered a local community’s higher standard.
To provide a context, below are links to some of the floodplain management orders/ordinances.
Note Chapters 9 and 13. They changed on September 1, 2018. Changes address building code issues for FEMA X zones. Zone X includes the 500 year flood plain. Many such areas flooded during Harvey.
Flood Damage Protection Ordinance
Harris County Guidelines for Unincorporated Areas
Cheat Sheet: Quick View of Changes Implemented in January
Montgomery County For Unincorporated Areas
Drainage Manual For Commercial Developments Greater than 15,000 SF
If a development affects a major waterway like the San Jacinto River, its wetlands, its flow, or endangered wildlife, the Army Corps will also review studies submitted as part of the permitting process. They would look at applications from the point of view of the EPA and Clean Water Act, especially Section 404. Section 404 of the Clean Water Act (CWA) establishes a program to regulate the discharge of dredged or fill material into waters of the United States, including wetlands. … For most discharges that will have only minimal adverse effects, a general permit may be suitable. This is the major focus of the permitting process now underway for the high-rise development in Kingwood.
The Clean Water Act also contains a section 401. It specifically focuses on how States and Tribes can use their water quality standards in Section 401 certifications to protect wetlands. States and Tribes can review and approve, condition, or deny any Federal permits or licenses that may result in a discharge to waters of United States within their borders, including wetlands. States and Tribes make their decisions to deny, certify, or condition permits or licenses primarily by ensuring the activity will comply with applicable water quality standards. In addition, States and Tribes look at whether the activity will violate effluent limitations, new source performance standards, toxic pollutants restrictions and other water resource requirements of State or Tribal law.
The Houston ordinance only applies to Houston’s jurisdiction. Houston does not influence neighbors and cannot control or force their policies on other jurisdictions. That is important since Kingwood is surrounded by Humble, unincorporated Harris County (Atascocita and Huffman), and unincorporated Montgomery County.
Understand that if a developer/individual meets the requirements identified in the floodplain ordinance(s), they can develop in the floodplain (including the floodway). Floodplain administrators must follow the law. However, they try to discourage dangerous floodplain development by “working to rule.” By strictly following all rules with no wiggle room, floodplain administrators can drag permitting processes out. A knowledgeable floodplain administrator can find problems with plans, surveys, and engineering reports for years. By requesting revisions, they can make life so difficult for applicants that it affects the economics of their developments. Eventually they may decide that a project falls into that great black box called “too hard to do,” and walk away.
Words of Wisdom
A regulator told me today that the more people who protest a permit, the harder they are to ignore.
If you have concerns about the high rise development in Kingwood, make sure you register them with the Army Corps (which is currently reviewing the permitting from a CWA 404 perspective). The deadline: January 29.
Comments and requests for additional information should reference USACE file number, SWG-2016-00384, and should be submitted to:
- Evaluation Branch, North Unit
- Regulatory Division, CESWG-RD-E
- U.S. Army Corps of Engineers
- P.O. Box 1229
- Galveston, Texas 77553-1229
- 409-766-3869 Phone
- 409-766-6301 Fax