Rights, Responsibilities, and Flooding Your Neighbor
Sept. 20, 2018
Update Sept. 29, 2018: The National Oceanic and Atmospheric Administration has released new rainfall statistics and adjusted rainfall frequencies in Texas and Houston.
Updated Oct. 29, 2018, with recent photo of completed massive erosion control project on Buffalo Bayou.
Over the past several years, in the wake of extreme floods, we have received numerous complaints about damaging “erosion control” projects on the banks of Buffalo Bayou – projects damaging not only to the natural functioning and ecosystem of the bayou but also potentially to people living and working up and downstream of the projects.
Property owners bulldoze the banks, build massive retaining walls made of concrete block or sheet metal, dump piles of concrete construction debris into the bayou, strip and line the banks with concrete riprap.
This in addition to stripping the banks of trees and vegetation, reshaping the banks, gouging out pathways, and landscaping with walkways and non-native flower gardens.
Do they have the right to do this? Is it a good idea? Who owns the bayou really? What permits are required, if any, to do these things?
And does the bayou itself have rights?
Did Retaining Wall Make Flooding Worse?
What happens if someone installs concrete riprap or a massive retaining wall that deflects the flow of the bayou away from their property and floods neighbors or damages public park property? This has happened repeatedly on Buffalo Bayou.
In one case, a large property owner in River Oaks, whose bank is likely affected by a large stormwater outfall directly across the way, installed a controversial concrete block wall along several hundred feet of bank in 2016, initially without a permit from the City of Houston. That armoring washed away during Harvey, and the property owner has now rebuilt the eroded bank, apparently dumping material into the channel, and installed a massive sheet metal wall that has alarmed residents across the bayou and elsewhere, threatening a narrow strip of land that the Houston Parks Board has been eyeing for a hike-and-bike trail.
Is that legal? Is it right? Does it work?
Shocker: The Port of Houston Owns Buffalo Bayou
This will come as a surprise to many people: The Port of Houston owns the submerged lands of Buffalo Bayou all the way from the bay to the headwaters. In 1927 the Texas State Legislature gave the Port of Houston “all the submerged lands lying and being situated under the waters of Buffalo Bayou, San Jacinto River, White Oak Bayou, Bray’s Bayou, Simms Bayou [sic], Vinces Bayou [sic], Hunting Bayou, Greens Bayou, Carpenters Bayou, Old River, Lost River, Goose Creek and Cedar Bayou, and all other streams within the authority tributary to the Houston Ship Channel, so far up said streams as the State may own same … for public purposes and for the development of commerce only …” (See Sec. 5007.004)
Many people with property on Buffalo Bayou would think they own to the center line of the channel since the Harris County Appraisal District describes it that way and taxes it too.
In 1937 the legislature set up the Harris County Flood Control District and gave it the “right to make use of the bed and banks of the bayous, rivers, and streams lying within the District, subject to the prior right and authority of the [Port of Houston].” (See Section 9.) (The Flood Control District, as well as the City of Houston, also owns property outright on the banks of the bayou, along with easements.)
The state also made the flood control district responsible for the “conservation of forests,” (Sec. 4), as we have often pointed out, a responsibility the district routinely ignores. Forest, trees, vegetation, green space are vital resources for reducing stormwater runoff, absorbing water, protecting the banks, cleansing the water and air, and generally making us all safer and healthier.
What Are Submerged Lands?
The legal definition of submerged lands in Texas rivers is not exact. According to one source, streambeds are the soil between the “gradient boundary” on each stream bank. The state Supreme Court has defined the gradient boundary as “a gradient of the flowing water in the stream, [which] is located midway between the lower level of the flowing water in that just reaches the cut bank and the higher level of it that just does not overtop the cut bank.”
Normally the cut bank is the outside bend of a meander. But in this case the reference is “typically an alluvial bank along a straighter portion of the stream that is not actively eroding,” points out former assistant state attorney general Joe Riddell.
The state definition of submerged lands seems approximate to the definition of Ordinary High Water Mark used to delineate federal waters. (See discussion below.) But generally the gradient boundary delineating stream bed ownership in Texas is slightly lower than the high water mark delineating federal waters, says Riddell, who worked in the natural resources division of the state attorney general’s office.
Who is Responsible?
Protection of our public streams and waterways, their adjacent floodplains and wetlands has two primary goals that concern us: ensuring the cleanliness of our waters and protecting us from flood risks by preventing any increase or rise in the existing flow of our natural drainage systems.
While physical ownership of the bed and banks may lie elsewhere, the federal government is responsible for protecting the water flowing through Buffalo Bayou and all navigable streams, their tributaries, floodplains, and connected wetlands. (See discussion of federal waters below.) Under the Clean Water Act, the Corps of Engineers has this enforcement responsibility, along with the Texas Commission on Environmental Quality (TCEQ). The TCEQ is responsible for certifying that any permits issued by the Corps for discharging dredged or fill material into federal waters, including the bayou, complies with state law.
In Texas a navigable stream is one that is useful even for pleasure paddling as well as, say, log flotation. The right of the public to access a navigable stream through public land is guaranteed in the Texas Constitution.
The Corps, under the Rivers and Harbors Act, is also responsible for regulating any construction in or on the bayou and any dredging or filling of the channel.
Protecting Us from Increased Flooding
To protect us from increased flood risk, the Federal Emergency Management Agency (FEMA), through the National Flood Insurance Program, also requires that construction in the floodways and floodplains does not cause an increase or rise in the flow of our streams. Or at least, not very much.
A floodway is the main channel and deepest part of a river or stream and part of the floodplain. The floodplain itself extends beyond the channel and over a generally flat plain alongside the river. This is where, after Harvey, for instance, we saw massive accumulations of sediment deposited next to the bayou. That’s what flooding rivers do: overflow their banks, slow down, and drop out the sediment carried from upstream. It’s why the floodplains and valleys of rivers are so fertile. And also how rivers naturally build up their banks.
FEMA, in order the minimize flood risk and regulate the insurance program, has more official definitions of “floodway” and “floodplain” and even several categories of floodplains based on 1. how much rain has to fall in order to flood those floodplains to a certain height (base flood elevation) and 2. how likely it is – considering the past record — that that much rain will fall.
A “floodway” officially defined by FEMA is “the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than a designated height.”
The base flood is the 100-year flood, which virtually everyone agrees is a ridiculous term and confusing. Currently in Harris County this base flood is 13 inches of rain within a 24-hour period. Our flood management/drainage system/policies are built on trying to handle that much water.
However, this definition of a 100-year flood is obsolete, as noted by professors Phil Bedient and Jim Blackburn of Rice University’s Severe Storm Prediction, Education, and Evacuation from Disasters (SSPEED) Center. Recent research indicates that the base or 100-year flood locally should be at least 16-17 inches of rain in 24 hours if not more. (pp 10-12) (Update 9.29.18: The National Oceanic and Atmospheric Administration has released new rainfall statistics and frequencies for Houston and Texas. The new 100-year flood is now 18 inches in 24 hours.)
That means more rain is falling more often. Harvey in 2017 was technically a once-in-5,000-20,000-year-plus event. (p. 30) The Memorial Day flood in 2015 and the Tax Day flood in 2016 were each 500-year floods. (p. 5)
The National Flood Insurance Program is a controversial taxpayer-funded program that subsidizes the reduced cost of private flood insurance premiums paid by renters, home and condo owners, and business owners in flood hazard areas in participating communities. Some people worry that providing cheap insurance to people who live in flood hazard areas encourages people to live there.
On the other hand, the insurance program does make an effort to discourage some activities that increase flooding.
Communities such as Houston and Harris County that participate in the program must “prohibit encroachments, including fill, new construction, substantial improvements, and other development within the adopted regulatory floodway unless it has been demonstrated through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that the proposed encroachment would not result in any increase in flood levels within the community …” (p. 6)
Here is an interactive map of current Harris County floodways and floodplains. Here is an interactive map from the City of Houston of Houston region floodways and floodplains. Note again that these maps are expected to change with new data to be released in October. Floodways and floodplains will get larger.
“We’re about to learn that … the new NOAA Atlas 14 data [will] translate into wider floodways and floodplains than we’ve been using in the past,” hydrologist Matthew Berg writes in an email. “In that case, some structures that were not held to floodway requirements under prior data will now be marked as in the floodway, realistically obstructing flow on a much more frequent basis.”
Rise/No Rise in Flood Waters
The engineering departments of the City of Houston and Harris County are responsible for making sure that construction and erosion control projects on the bayou and elsewhere meet this federal “no rise” requirement before issuing permits. Not that that’s easy to do when developers and property owners are wealthy, influential, and prominent members, even heads, of parks and other boards and commissions. City and county employees must also determine that projects have the proper approval from the TCEQ and the Corps.
Note that despite this “no rise” requirement, Harris County has the most and fastest rising streams in the state of Texas, according to a study by hydrologist Berg. These include Greens, Keegans, Langham Creek, White Oak Bayou, Cole Creek, Brickhouse Gully, Sims Bayou, Bear Creek, and Buffalo Bayou. (pp. 22-23)
Apparently there are exceptions to the “no rise” requirement. (See page 6.) Or something is missing from the formula.
A 2013 report from the Association of State Floodplain Managers criticized the federal insurance program for allowing development in the floodways as long as the impact did not increase flood elevations by more than a foot. (p. 4) “Anything greater than zero is problematic” and “perpetuates an upward trend of increased flood damages,” noted the report (p. 16). “Small encroachments into a floodplain in and of themselves may have a negligible impact on flood elevations. However, the combined, incremental effects of human activity, referred to as cumulative impacts, can cause significant increases in flooding.” (p. 4)
Harris County allows zero increase in flood elevations in the floodway. “Under the conditions of obtaining a permit, no development or other encroachment, including fill, is allowed in a floodway which will result in any increase in the base flood elevations within the floodway during discharge of water of a base flood,” wrote Harris County Engineering Department Permits Manager Jesse Morales in an email.
However, Harris County only regulates construction activities in unincorporated areas of the county.
The City of Houston likewise prohibits any increase in base flood flow in the floodway. “A floodway development can only be approved if the submitted engineering study shows that the development will result in 0.00 feet of rise in the base (100-year) flood elevation in the entire watershed,” writes Erin Jones, public information officer for the City of Houston Public Works Department, in an email. (Emphasis added.) Jones notes that this requirement is outlined in Ch. 19 of the city’s guidelines for development in the floodplain. (See pp. 45-47.)
It’s unclear whether a proposed project would have to show no increase in flood elevations for your neighbor immediately downstream or across the way.
That’s the Floodway. What about the Floodplain?
The floodplain managers’ report also noted the value of reserving floodplains adjacent to streams for floodwater overflow and storage. “The floodplain provides a valuable function by storing floodwaters. When fill or buildings are placed in the flood fringe, flood storage areas are lost and flood heights will increase because there is less room for the floodwaters.” (p. 22)
The report criticized the “hydraulic concept” that the flood insurance program uses to calculate the floodway. “The concept does not address hydrologic changes that could increase flood levels such as the loss of floodplain storage, increase in impervious surface, or changes in precipitation patterns.” Nor do the mapped flood zones consider “future land use conditions,” stated the report. (p. 22)
In addition, the floodplain managers’ report criticized the practice of allowing higher flood elevations caused by construction, constriction, or encroachment in the floodway to be balanced by increasing the flow conveyance, i.e. reducing the roughness of the channel or floodplain. “Reducing roughness” (friction) means removing native vegetation and hardening the area. “However, this increases the flood flows velocities and increases the erosive properties of the flood flows. In addition, it removes valuable natural habitat in the floodplain,” stated the report. (p. 23)
Both the City and the County require that construction in the floodplain (as opposed to the floodway itself) result generally in “no adverse impact,” though the concept is very broad. However, as outlined by the flood control district, it does include a general policy of not flooding your neighbor. (See p. 29)
“Our regulations address the concept of ‘no rise’ as no net fill in the floodplain,” writes Darrell Hahn of the Harris County Floodplain Management Office. (See p. 114) “The Harris County Flood Control District addresses it as no adverse impact. It is policy that any project reviewed by the Harris County Flood Control District is required to prove that results are at most 0.0 rise in Base Flood Elevation.”
No net fill means you can’t bring in dirt, for instance, without excavating an equal amount of dirt because that will reduce the stormwater storage capacity of the property and increase runoff into the drainage system. Except that you can compensate or “mitigate” by excavating somewhere else.
The City has similar regulations for construction in the floodplain (see pp. 52-53) , though the city allows some increase in flow (.5%) or loss (.5%) of capacity (conveyance) in the bayou and channels and natural streams crossing the floodplain, including prairies and forested areas. (See pp. 29-30)
Neither the City not the County addresses the usefulness or value of native trees and plants for controlling bank erosion and absorbing, slowing, and cleansing stormwater runoff. In fact, the flood control district actively discourages trees and vegetation along our waterways, known as riparian buffer, as impediments to conveyance. The district, apparently responding to public pressure for a manicured look, spends millions of dollars mowing the grass along our channels three times a year, which causes the grass to put its energy into growing upwards instead of growing longer roots that absorb stormwater and protect against erosion.
A new study released September 5 assesses the high economic value of riparian buffers in reducing flooding and erosion, cleansing the water, increasing property values, and more. (See also this earlier study. And here.)
The County, to its credit, does encourage trees. (p. 84)
Experts recommend a minimum width of ten feet of native plants and trees alongside an urban stream for effective erosion control and other benefits. Here’s some advice on restoring a bank on the bayou into a healthy, protective riparian area. Here are some Best Management Practices.
The Problems with Bank Hardening
FEMA encourages the use of green or natural approaches and soft structures rather than hard engineering solutions like retaining walls and riprap to protect against bank erosion.
Hardening the banks with metal, stone, or paving, compacting the soil on the banks with heavy equipment, stripping trees and native vegetation that absorb runoff as well as floodwaters, are all activities that increase and alter the flow in the stream and thus the risk of flooding and erosion. Streams and bayous, constantly eroding and rebuilding, naturally seek a dynamic equilibrium, a balance between flow and sediment, slope and speed, width and depth, and hard structures destabilize the balance, which can lead to unintended consequences. (See here and p. 29)
In addition, many local erosion control projects mistake vertical slumping and sloughing, the most common type of bank collapse on Buffalo Bayou, for lateral erosion caused by the flow of the stream, and property owners spend a lot of money on inappropriate (not to mention ugly) projects. Erosion and deposition of sediment, a constant process, are natural and necessary functions of a stream.
The federal flood insurance program recognizes the “the natural and beneficial functions of a community’s floodprone lands” and encourages “protection of natural floodplain functions” by providing lower premiums or greater discounts to communities that meet these goals.
How Are We Doing?
The current Harris County rating is 7 on a scale of 1 to 9, with 9 being the worst and 1 being the highest, offering the greatest discount (45 percent) on insurance premiums. The federal discount for flood insurance in Special Flood Hazard Areas (SFHA or 100-year floodplain) in Harris County is 15 percent. Outside of the 100-year floodplain the discount is 5 percent.
The current City of Houston rating is 5, somewhat better than Harris County. That rating offers a discount of 25 percent for policyholders in the 100-year floodplain and 10 percent outside of it.
Flooding Your Neighbor and Other People
Under Texas law, “no person may divert or impound the natural flow of surface waters in this state, or permit a diversion or impounding by him to continue, in a manner that damages the property of another by the overflow of the water diverted or impounded.”
The Harris County Flood Control District has guidelines, reviews plans submitted to city and county engineers, and consults with local floodplain administrators. But the district itself has no enforcement powers.
In the name of flood risk reduction, both the City and the County continue questionable and costly practices of “improving” our waterways through deepening, widening, stripping, straightening, mowing, and even hardening the channels. (Not to mention installing and replacing bigger and bigger drainage pipes.) These unsustainable practices, geared towards collecting and moving more water as fast as possible, are considered outdated, ineffective, unnecessarily expensive, environmentally damaging, and even counterproductive by leading flood experts. The modern approach is to slow and stop stormwater runoff before it floods the stream, to manage rain runoff in place, to widen the natural floodplain of the river to allow it to slow and absorb floodwaters. And to get out of the way.
“Preserving old stands of trees, natural swales, wetlands, oxbows, vegetated riparian areas, and meanders; building small weirs, sediment structures, wet gardens, and setback levees; lengthening streams, and accepting large woody debris in the channel are useful techniques. Using these practices to work with the natural motion of the river is more effective – and less expensive – in reducing flood damage and helping us realize benefits from the water.” (p. 137)
What Are Federal Waters?
Though the exact definition of federal waters is still being challenged in court, including by the State of Texas, the operating rule is that the Corps and thus the TCEQ regulates any activities (dredging and filling, for instance) taking place below the Ordinary High Water Mark (OHWM) of a navigable stream, including tributaries (even small creeks with bed and banks) and connected wetlands.
Though also subject to interpretation, the Corps defines the Ordinary High Water Mark as “the line on the shore established by the fluctuations of water and indicated by physical characteristics such as a clear, natural line impressed on the banks, shelving, changes in the character of soil, destruction of terrestrial vegetation, the presence of litter and debris, or other appropriate means that consider the characteristics of the surrounding areas.”
In addition, as mentioned above, under the Rivers and Harbors Act of 1899, the Corps regulates any “work or structures in, over or under navigable waters of the United States.”
Who Needs A Permit?
Bank stabilization projects dumping fill for 750 linear feet or more along the bank of the bayou below the Ordinary High Water Mark (OHWM) require a permit from the Corps.
Plans to dump an average of one cubic yard of fill per linear foot for 1,000 linear feet or more below the OHWM require a permit from the Corps.
A pre-construction notice must be filed with the Corps for any project that involves a discharge into a special aquatic site (like a wetland) or is in excess of 500 feet in length, or that involves a discharge of greater than an average of one cubic yard per running foot below the OHWM.
Some smaller projects – those that impact less than 1,500 linear feet of the stream, for instance – may still require a Corps permit but may not need a review by the TCEQ as long as they incorporate Best Management Practices – silt fences, for instance — for controlling erosion and sediment loss during construction until the bank has been stabilized.
Even the Flood Control District must have a permit from the Corps of Engineers to dredge and “improve” our waterways. The district has a General Permit to dredge and fill for “routine maintenance and repair.” It specifically prohibits deepening and widening channels, channelization or the use of concrete except to replace existing concrete, or damaging special aquatic sites like wetlands. That permit expires on Dec. 31, 2019.
Any private citizen inside the city limits who wishes to conduct any “construction activity” in the floodway or floodplain must have a permit from the City of Houston Floodplain Management Office. According to the Jamila Johnson, director of that office, “to obtain a floodplain development permit, the applicant is required to provide a Certificate of Compliance indicating that the applicant has received all permits, licenses or approvals required by federal law, statute or regulation or required by any State of Texas statute, rule or regulation – this would include required approvals by the [Army Corps of Engineers].”
Outside of the city limits, Harris County also requires a permit to build “fences or fence-type walls” in the floodway or floodplain “provided it can be demonstrated the flow of the base flood will not be impaired and that base flood elevations will not be increased during the discharge of the base flood.” (p. 39)
Property owners who lose bank to erosion or a shifted channel may not legally rebuild that bank. The property line shifts with the shifting of the channel, says Riddell. “When the bank gets eroded the new gradient boundary will be on the new bank. A riparian landowner can gain or lose land depending upon whether the bank gains or loses soil.”
Is It Right? The Rights of Nature
Just because the authorities will give you a permit to do something doesn’t mean it’s a good thing to do.
In fact, the laws that are supposed to protect our environment, many of them dating from the 1970s, have been criticized for doing just the opposite: giving the power to government agencies to permit damage to the environment, destroy wetlands and streambanks, build in floodplains and floodways, cut down forests, etc.
A renewed movement, based on ancient law, recognizes that rivers and riverbanks, the air, all the water, the oceans and shores, our environment and climate, even wildlife, are a public trust, and that our government has an obligation to protect our natural assets as the common property of the people, for the benefit of all, including for future generations.
If corporations can have the rights of persons, rivers should too.
Respecting the process and power of nature, understanding how rivers and streams work, makes us all safer.
Filing a Complaint
What to do if you think someone might be dumping or building illegally on the bayou? Or in a way that is damaging?
Here is how to complain to the City of Houston floodplain management office.
Here is how to complain to the permits office of the Harris County Engineering Department.
Here is how to complain to the Galveston District of the Corps of Engineers.
Here is how to complain to the Texas Commission on Environmental Quality.
In addition, you can report acts of pollution to air, water, or land, by calling the Houston Police Department’s Environmental Investigations Unit at 713-525-2728.
You can also report chemical spills, possible illegal use of pesticides, and other environmental violations to the Environmental Protection Agency.
Dumping of debris into ditches, streams, or bayous is a violation of the Houston Code of Ordinances Section 28-1. To report a violation or a maintenance problem, call the City’s Service Helpline by dialing 3-1-1.