There are two things I have learned about public policy issues. First, they are always more complex than a causal examination suggests. Second, policies adopted with the best of intentions frequently have unintended, negative consequences. Both of these principles are evident in the amendments that the City made to its flood ordinances in October, 2006. These amendments have spawned a flurry of protests and objections. The opponents of the amendments have even organized their own website. See http://www.houstonfloodway.org/index.htm
There are many issues involved in this dispute, but at the heart of the controversy is a provision in the amended ordinance that bans all construction in the floodways and limits improvements to existing structures to 50% of their value. The 50% limitation is cumulative over a 10-year period.1
At first blush, stopping a lot of new construction in areas likely to flood seems like a pretty common sense notion.
In addition to the general idea that people should not be building in an area likely to flood, the City had another reason for amending the flood ordinances. FEMA administers the National Flood Insurance Program. One of its duties is to rank cities based on their efforts to minimize flooding. Residents in cities that score higher on FEMA's ranking system (referred to as the Community Rating System or CSR) pay lower flood premiums. When I was on council and mayor of Kemah, we were able to substantially lower our residents' premiums through aggressively adopting various flood control measures. Likewise, the City of Houston's ratings have significantly improved in recent years, saving Houstonians thousands of dollars in flood insurance premiums. So it is clear that the City should be constantly working to improve our flood control measures.
Many of those who have been very significantly and adversely affected by these amendments have ascribed various sinister motivations to the 2006 amendments. Candidly, I have found no evidence that suggests any motivations other than attempting to improve the City's flood control measures and lower Houstonians' flood insurance premiums. But as Samuel Johnson once said, "The road to hell is paved with good intentions." And this is where some of our neighborhoods feel that they have been sent by these amendments.
It will probably surprise those not familiar with this subject that the definition of what constitutes the floodway is open to some considerable interpretation. I think most of us would assume that the floodway would generally be the area within the banks of the bayous. However, it turns out to be considerably more complex and can cover a much larger area.
The CRS system actually establishes two concepts regarding areas subject to flooding - the floodway and the flood plain. The flood plain refers to areas in which there is a 1% chance of flooding in any year. This is frequently referred to as the 100-year flood plain. The floodway defined at any bayou or channel section as the minimum width of floodwater conveyance to keep flood waters from rising above one foot above the 100-year flood plain elevation. I know, about as clear as mud.2
But the general idea is that we want to keep the floodway open to keep people upstream from flooding.
Therefore, the floodway is not an area that is readily demarcated by a physical feature like the bayou banks. It must be calculated by hydraulic engineers based on floodwater flow rates and channel characteristics within the watershed. New maps are periodically issued maps showing the floodways and the 100-year flood plains.
But here is where the rub comes in. Those maps change from time-to-time based on new rainfall data, changes in the hydraulic characteristics of the watershed, or changes in the calculation methodology. The amendments to the City's flood ordinances coincided with such a re-drawing of flood maps based on new elevations that were developed as a result of the Tropical Storm Allison Recovery Project (TSARP) using new Light Detection and Ranging (LIDAR aerial mapping technology and some changes in the calculation methodology.3
The results substantially changed the areas included in floodplains and floodways across the City and County. In some neighborhoods, such as along White Oak Bayou, the areas added to the floodways included many homes and vacant residential lots not previously recognized as being within floodways. With the combination of the new floodway maps and the City ban on new construction on floodway construction, many property owners suddenly found their properties, many of which had never flooded, substantially devalued and some virtually worthless.
Interestingly, the FEMA regulations do not require that the City prohibit new construction in the floodway as it has done in the amended ordinance. In fact, there is no such ban imposed by the County in unincorporated areas. Rather, FEMA requires that the City must regulate construction in the floodway to prevent any new construction from causing additional flooding in the upstream floodplain. Also, it is not clear whether the City gets any credit under the CSR system for the total ban.4
Under these circumstances, I believe that the City should revisit the October, 2006 amendments. At a minimum, the outright ban of construction in the floodway should be lifted in favor of a system that would regulate the degree to which any new construction could impede the flow of flood waters. By building with pier and beam construction, it is my understanding the impedance can be minimized or mitigated. Also, the 10-year cumulative damage provision is not required by FEMA and should be revised as well.
When you live in flat coastal plans flooding is inevitable. As result flooding has long been a long-standing and chronic problem in Houston, bringing misery to hundreds of thousands of our neighbors. Therefore, the City should be commended for aggressively moving to reduce this menace. However, as with any initiative, the rights of the minority must be weighed against the general public welfare. In this case, I feel that we have abridged the rights of these property owners to a far greater extent than is justified to protect the greater good.
121 North Post Oak Lane, #401
Houston, Texas 77024
PS: If you would like to know where your property is with respect to the floodways and flood plains, you can find out at http://maps2.tsarp.org/tsarp/
The City has, by administrative rule, made significant exceptions to the 50% limitation.
The actual definition per FEMA regulations is "Floodway means that portion of the floodplain which is effective in carrying flow, within which this carrying capacity must be preserved and where the flood hazard is generally highest, i.e., where water depths and velocities are the greatest. It is that area which provides for the discharge of the base flood so the cumulative increase in water surface elevation is no more than one foot."
LIDAR is technology similar to radar. With this technology an airplane flying over any point can determine to a high degree of accuracy that point's elevation.
The CSR rules have a point system that awards points for specific flood control measures. There are no points for a total ban of construction in the floodway under this point system. However, FEMA generally opposes wholesale construction in the floodways and has some subjective discretion over the ultimate ranking assigned to the City.