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Houston -- We Have a Problem!
Houstonians agree that flooding is one of the most serious problems facing us.
While Houston is best known worldwide for such things as its renowned Medical Center,
Houston is also becoming well known for its problems, such as air pollution,
traffic congestion, and flooding.
A 1998 National Wildlife Federation study entitled
"Higher Ground" ranked Houston and Harris County third and fourth of the top 200
repetitive flood loss communities in the United States. The only communities ranked
higher are Jefferson Parish and New Orleans, both of which are below sea level.
And our flooding problem is getting worse. Uncontrolled development (i.e. urbanization) results in more water flowing off of property, and at a faster rate, into our many ditches, creeks and bayous, which are unable to handle the excess water, resulting in flooding. Even though our government officials contend that there are adequate controls on development to prevent additional flooding, the fact is flooding and flood damages are on the rise in Houston and Harris County.
Both the City and the County have the power and the duty to protect the public by controlling floodwaters and requiring that new development not increase flooding. Yet both of these governments have failed to do so.
Houses and businesses have been allowed to be built in or near the floodplain only with the approval of these governments. Yet, when these properties flood, the response of these same governments who approved the locating of these properties in flood-prone areas is to either blame it as "an Act of God" or contend that no one knew it was a flood-prone area. Both of these excuses are misleading, intended to direct the public away from the real problem, which is that our elected officials either don't know or don't care about flooding problems in Houston and are not willing to do enough about them to make a difference. It is time for that to change.
WHY IS FLOODING SO BAD IN AND AROUND HOUSTON?
There are three primary natural reasons for Houston's flooding, over which we have no control - heavy rains, flat topography, and numerous bayous.
However, there are three other reasons that such natural flooding becomes a problem - inappropriate and/or misplaced development, an un-informed or misled public, and irresponsible or ineffective government action, all of which we are in control, if we so choose.
Being close to the Gulf of Mexico, Houston is exposed to heavy rains, whether they be from thunderstorms, tropical storms or hurricanes. Rainfall on the order of 10, 20 and even 30 inches in less than a day is not uncommon in this area. It is something we all learn to live with being near the Gulf Coast, along with the humidity and warm weather.
It is also something that should come as no surprise to those who are designing and constructing residential and commercial buildings in this area, those who should be designing sufficient safeguards to make sure that these buildings are safe from being flooded during these heavy rains. Obviously, they are not.
Also, being along the Gulf, the land is fairly flat, and rainwater does not move away very quickly. Likewise, the natural forces that created the original streams and bayous in our coastal region provided a channel that only had the capacity to handle the runoff from small storms. . During larger storms, our creeks or bayous overflow, and floodwaters spread out over this flat area. As a result, our floodplains are fairly wide. Because we have a lot of creeks and bayous, we also have a lot of fairly wide flood plains, or flood-prone areas, most of which cross through the heart of the city. A large percentage of Harris County was once covered by floodplains long before anyone dreamed of building a city here. Flooding is natural.
Given these natural conditions, developing homes and businesses in the Houston area that would be safe from flooding was obviously a challenge, but one that is not overly difficult, especially for a community proud of its technical expertise in areas such as space exploration, medical research, oil and gas, and computer technology. Surely we could have figured out how to build a house that won't flood every few years!
SO, WHAT HAPPENED?
Our city and county governments control development within their jurisdictional
boundaries through a platting and permitting process. Every subdivision of property is required to have a plat of the subdivision approved by the City and/or County, and must follow certain rules and regulations to get the plat approved. Every home or building is required to obtain a permit from the government before it can be constructed in order to make sure that the structure will be safe (from flooding, for example) and that other property will not be adversely affected by the construction of such a building.
While the Harris Count Flood Control District (HCFCD) does not issue plats or permits, it does review plats and other permit applications to insure compliance with its design criteria, rules and regulations. Developers and their engineers are aware of these rules and regulations and attempt to insure that their designs are in accordance with them; otherwise they cannot get a plat or permit.
However, if these rules and regulations are not adequate to ensure safe construction, inappropriate development will occur and problems will arise. This is what happened in Houston.
Houston and Harris County joined the National Flood Insurance Program (NFIP) in 1974
and 1973, respectively, which allows for a community to offer federally sponsored
insurance for covering losses due to flooding. As part of joining that program, a
community is required to adopt and follow certain rules and regulations pertaining to
development in flood-prone areas, or special flood hazard areas, in order to minimize
the potential for having flood damages occur when the heavy rains fall.
In addition,
the community is provided with flood plain maps (such as flood insurance rate maps or
FIRMs), published by the Federal Emergency Management Agency (FEMA), that show where the flood-prone areas adjacent to the creeks and bayous are located so that both the community leaders and the public can be aware of the flood risks in the area and take steps to protect their homes and businesses from flooding. And finally, the community is supposed to prevent future development outside of these flood-prone areas from increasing the flood risk for those properties located in or near these special flood hazard areas.
Our elected officials in Houston and Harris County decided to adopt the minimum rules
and regulations required by the NFIP, rules that were developed for use nation-wide as
a minimum standard. As such, the unique conditions that exist along the Gulf Coast
were not being specifically addressed by these minimum rules.
For example, the NFIP allows for filling in the floodplain so long as floodwaters will not increase by more than one foot. While a one-foot increase in flood levels may not be significant in many areas of the country, here along the Gulf Coast with our flat terrain, a one-foot increase in flooding generally encompasses a large area that would not otherwise have flooded but for the filling in of the floodplain. There were many communities throughout the country that adopted stricter regulations than the NFIP minimum, such as not allowing any increase (or less than one-tenth of a foot) in flood levels due to filling in the floodplain. For example, here in Texas, San Antonio and Austin both have stricter criteria even though their terrain is not as flat as ours.
But not Houston! Does one wonder why the flooding problem continues to worsen in our area?
Likewise, the NFIP minimum rules are generally based upon the 100-year flood event.
This is the flood that is supposed to occur or be exceeded on the average only once
every 100 years. Another way of saying it is that this is the flood that has a 1%
chance of occurring every year. In
Storm Date Total Rainfall Tropical Storm
June 1973 15"
June 1976 10"
July 1979 43" Claudette
Sept. 1983 9"
May 1989 14"
June 1989 12" Allison
May 1992 8"
Oct. 1994 29"
Sept. 1998 15" Frances
June 2001 35" Allison
and recommended the 100-year rainfall be increased from about 13 inches to about 14 inches in a day. This analysis was based on averaging the rainfall at 11 locations throughout Houston, most of which were on the wet side, where few, if any, of the major storms have occurred. For example, during Tropical Storm Allison, the highest 12-hour rainfall used by the consultant at any of the 11 locations selected was about 17 inches, even though the northeast side of Houston experienced amounts in excess of 25 inches. A separate analysis was done by the consultant without averaging the rainfall at the 11 locations, but rather using the maximum value that occurred at any of these locations, reasoning that " . . . since these maximum values occurred at a location in the network, then they are representative of maximum precipitation depths possible within the network." The results of this analysis showed the 100-year rain for the Houston area is closer to 19 inches, rather than the 13 inches currently used. That's 50 percent more rain than currently used to determine the floodplains along our creeks and bayous! And it's based upon rain amounts that are not even close to the highest rainfall we have seen in Houston over the past few years! Why are our elected officials unwilling to use the real numbers to show us what the real floodplains and flood risks are in Houston? Maybe our "100-year" flood events are more like 5 or 10-year events and should be treated as such for design and planning purposes in the Houston area.
Houston and Harris County have similarly understated the mitigation that would be required by new development in order to make sure that existing homes and businesses would not experience increased flooding. Studies that were conducted in the Houston area in the mid-70s indicated that the highest rates of storm water runoff would increase by at least three times, and as much as 5-10 times, due to urbanization (i.e. development) depending on the type of development and the size of the storm. With this knowledge, our elected officials adopted criteria in the early 1980s for developers to follow so that there would be "no adverse impact" from future development. For example, every new development would need to have a detention pond either on-site or off-site so that the increased storm water runoff caused by the new development would be sent into, held and then released from this pond in such a way that the increase would be reduced back down to the runoff associated with pre-development conditions. Sounds good! Yet, even since the adoption of these so-called "no adverse impact" criteria, there have continued to be significant increases in storm water runoff entering our bayous over the past 20 years, as evidenced by
Figures 1 and 2. How can this be happening when there is supposed to be a "no adverse impact" policy on new development and criteria in place to make that happen? There are several reasons.
For example, our elected officials decided that for developments under 10 acres in size, no detention ponds would be required; rather, a fee could be paid to the Harris County Flood Control District (HCFCD) by the developer and it was left up to the HCFCD to provide the necessary improvements to handle the increased runoff. In addition, amount of the fee to be paid by developers necessary to compensate for their increased runoff was set too low, and the Harris County Commissioners have chosen not to fully fund the HCFCD in order to pay for the implementation of these needed improvements. Normally, such impact fees are regulated under a state statute to prevent this from happening. But an exception was given to Harris County's impact fees, that allow them to avoid being regulated, so long as the fees never change (which they have not).
Also, the criteria established for the detention ponds that do get built by developers allow for the storm water to be released from these ponds at a rate much higher than pre-development conditions. For example, some of the surrounding counties to Harris County (Fort Bend and Brazoria) limit the maximum rate water can be released from a detention pond to 0.125 cubic feet per second (cfs) per acre, in order to fully mitigate the increase in storm water runoff caused by development. Yet, in Harris County and Houston the criteria allows for up to 10 times as much water to be released from a detention pond, exceeding the amount of runoff that used to flow off the property before it was developed. In addition, if a property is deemed to be “previously developed” in any way, it is then exempt from the mitigation requirements. This is why so much of the redevelopment occurring in the inner city is not being mitigated.
The above examples of the inadequate criteria adopted and used by our city and county officials over the past two decades to "control" development explain why they do not result in "no adverse impact"; instead, they actually increase flooding.
While the flooding problems in Houston and Harris County are getting worse, the public is being kept in the dark about it. Even though the HCFCD has the most technical knowledge about the flooding situation throughout the city and the county, the district has no web site available for the public to access any information. Likewise, the City of Houston's Public Works department, which has the most technical information about flooding within city government, also has no web site for the public to access such information. This is a clear indication that our two government agencies seem to have "other priorities" than providing key information to the affected public about one of the most serious problems facing Houstonians.
In the early 1980s, the HCFCD developed computer models for most of the creeks and bayous throughout the County, including the City of Houston, as part of its Flood Hazard Study. The HCFCD then created the floodplains for these creeks and bayous using its computer models and submitted this data to FEMA for publishing the official floodplain maps (FIRMs) for the City and County in 1985. Since then, the HCFCD has maintained and updated its computer models to reflect new development and other drainage improvements throughout the County. Yet, even as flooding conditions were getting worse over the next 20 years, most of these official floodplain maps were not being regularly updated or corrected to reflect current conditions, as required by FEMA regulations.
Because of this, the city and county were still using old floodplain data developed in the early 1980s as the basis for adopting official floodplain maps to give to the public and to use in the permitting process for approving new construction near our creeks and bayous. Obviously, new homes and buildings were being approved for construction in the floodplain even though the "official" floodplain maps were not showing it; and because new projects were not being shown to be in the "official" floodplain, any fill that was brought into the real floodplain was not having to be mitigated, only increasing the problems elsewhere.
"HOUSTON - WE HAVE A SOLUTION!"
WHAT OUR ELECTED OFFICIALS SHOULD DO
TO ADDRESS THE FLOODING PROBLEMS IN HOUSTON
PROBLEM NO. 1: PUBLIC ACCESS TO ACCURATE FLOOD INFORMATION AND THE LACK OF RESPONSIVE GOVERNMENT
The general public has little or no access to information from the city or county about flooding. The only information readily available is the FEMA floodplain maps (FIRMs), which, in our rapidly changing urban area, are often based on outdated and inaccurate computer models of Houston's creeks and bayous. Tropical Storm Allison in June 2001 revealed how inaccurate our current floodplain maps are and has led to a total redo of the floodplain maps throughout Harris County, based on new topographic data (LIDAR) and new computer modeling (HEC-HMS and HEC-RAS). These new floodplain maps were due to be released to the public for review in March 2003. It is important to note that even as draft maps, they will constitute the “best available information” about the size and location of our floodplains. Therefore, contrary to current practice, this new information should be used immediately upon release for regulation of development and floodplain management.
SOLUTIONS:
I. Make public access to flood information easy and reliable.
a. Create a comprehensive city/county website that is responsive and informative.
i. Put current "official" floodplain maps (FIRMs) on website and keep it updated (along with corresponding computer model data).
ii. Put any updated floodplain information on website, with status of such information, and keep it updated (along with corresponding computer model data)..
iii. Put local buyout information (including rules, policies, and currently available funding) on website and keep it updated.
iv. Provide dates of watershed and floodplain related public meetings on website.
v. Provide descriptions of all city flood policies on website. It is the obligation of local government to make information available for citizens of what is being done to protect them.
vi. Provide information on flood insurance on website.
b. Ensure equal access to information
i. Information posted on the web such as updated flood maps, clearly outlined city policies on flooding, etc. should also be available in print for those who don’t have internet access.
ii. Information should be available at locations citywide for those who can’t come to city hall during business hours.
c. Create City Council Flood Committee
i. Create a specific committee of elected government officials to address watershed management and flooding problems.
ii. Hold public meetings of the committee at least monthly to discuss and receive public input regarding flooding problems and solutions being pursued.
iii. Provide floodplain administrators with technical expertise to understand and deal with development issues and the permitting process.
II. Obtain and use best available information.
a. Utilize more restrictive floodplain information in permitting process (e.g. when draft floodplain maps are released to the public). It is better to play it safe than to put people and public and private investment at risk.
b. Conduct annual review of floodplain information to verify its accuracy as compared to actual flood data.
c. Coordinate and share with other government agencies flood-related data and information.
d. Utilize more realistic analyses of storm frequency data developed specifically for the Houston area (e.g. showing 19 inches/day as 100-year rain) for mapping floodplains and floodplain management regulations.
PROBLEM NO. 2: EFFECTIVE CONTROLS ON NEW DEVELOPMENT
New construction and development must obtain a plat and/or permit from either the city or the county (or both) in order to build in or out of the floodplain and must conform to certain standards, codes and design criteria. The drainage criteria that are currently used by the City and County are ineffective and actually result in increased flooding. As one example, developments of less than 10 acres are exempt from having to provide detention to mitigate the increase in runoff that will occur. As another example, the amount of water allowed to be released out of the detention ponds is up to 10 times more than allowed in neighboring counties, exceeding the amount of water that ran off the property before it was developed. Floodplains are allowed to be filled and cause up to a one-foot increase in flooding on other property elsewhere along the creek or bayou. Such "controls" on new development are not consistent with the "no adverse impact" policy of our city and county government, and actually cause more flooding in our community.
SOLUTIONS:
I. Close loopholes in City of Houston and Harris County "no adverse impact" policy by adopting effective controls on new development.
a. Eliminate exceptions (less than 10 acres) to requirement for fully mitigating increased runoff by new development.
b. Require full mitigation due to new development be in-place before development occurs.
c. Require certification by a professional engineer that new development has been fully mitigated and there will be no downstream impact due to the new development.
d. Require maximum allowable release rate from detention ponds to not exceed 0.125 cfs/acre.
e. Require that no increase in flood levels be allowed due to any development activity in the floodplains.
PROBLEM NO. 3: EFFECTIVE SOLUTIONS TO REDUCE FLOOD DAMAGES
Flooding in and around Houston is inevitable, given our location near the Gulf Coast, but that does not mean that homes and businesses have to flood whenever we have heavy rains. The ineffectiveness of our previous government officials in solving the flooding problems and preventing them from getting worse does not mean this trend has to continue. Trying to build bigger ditches in a piece-meal approach is not an effective solution to the problem, but only moves the flooding from one place to another.
SOLUTIONS:
I. Comprehensive watershed planning
a. Perform all planning on a comprehensive watershed-wide basis in conjunction with other governmental entities.
b. Provide adequate funding for the planning and implementation of necessary flood damage reduction projects to eliminate potential for flood damages within 10-year floodplain.
c. Make detention/retention the primary component of any watershed-wide flood damage reduction project whenever possible.
d. Re-evaluate and update all impacts fees in Harris County and do so in accordance with state law.
II. Buyout as a solution component.
a. Incorporate buyout into the overall plan for eliminating flood damages.
b. Develop clear buyout policies and procedures
i. Establish a permanent city-funded buy-out program to acquire the most frequently damaged structures and undeveloped properties that are deepest in the floodplains, abutting stream and bayou corridors. These buy-out dollars would complement flood control dollars and the federal disaster mitigation money that we only receive after a major flood.
ii. Include a program for purchasing homes already on the market along bayous to create greenways/park space, which will also serve as detention
iii. Include a public policy as to how buyouts will be prioritized
iv. Make this information available on government website.
c. Establish a program to promote elevating or rebuilding frequently damaged structures within neighborhoods that are distant from stream corridors and in the shallow fringe areas of our floodplains. This will help maintain the integrity of neighborhoods and counteract the checker boarding that can occur in neighborhoods.
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