Letters of Support - Harris County Flood Control District

13-0713
Why the Need for MPDP
by K. Shanely
V. 2013
July 13
Why the Need for the Memorial Park Demonstration Project
1. Buffalo Bayou is no longer a natural stream. Every stream is inextricably linked to its w/atershed, every
stream is shaped by its watershed and every stream evolves with its watershed. 95% of the Buffalo
Bayou watershed below the dams has been urbanized to suburban densities; and the influx of millions
of new people to the Houston metropolitan area over the next several decades will result in on-going,
gradual increases in density within the Buffalo Bayou watershed.
2. The past urbanization and the future urbanization have utterly changed the response of the watershed
to a rainfall event, with rapid, flashy peak flows within a few hours after a storm event, in comparison to
the pre-development response measured in days and weeks. The Addicks and Barker Dam
discharges just further exacerbate the stresses placed on the bayou by human activities.
3. Buffalo Bayou will seek to establish what fluvial geomorphologists call a 'dynamic equilibrium' with the
new and changing conditions in the watershed, but for this bayou, it will be a moving target for many
decades to come. The bayou will work to change its horizontal and vertical geometries in response to
the changes forced on it, and these might result in changes of hundreds of feet horizontally and,
depending on the location, several feet vertically, as has already occurred in multiple locations along
the bayou.
4. This means that the bayou will want to eat into real estate already occupied by gardens structures,
houses, condominiums, bridges and utilities. The owners of those properties will fight the bayou and,
as they have been doing for decades already, they will line the banks of the bayou with steel sheet
piles, bags of concrete, timber walls, gabions, and giant heaps of rubble. They will do what they think
they need to do to protect their property. Anyone who has taken a canoe or kayak trip down the bayou
will have seen the effects of these band-aid solutions, where one property owner's solution may very
likely just shift the energy of the bayou to the opposite bank or to the downstream property owners.
Given time and the changing bayou, in a few years most of the bayou will be lined with band-aid
solutions installed ad-hoc by property owners intent on protecting their assets, but in the end
destroying the natural character of the stream.
5. The bayou is a moving column of water, full of energy, and the only way to properly address changes
to the river environment is to take into consideration both banks of the bayou, to acknowledge the
changes to the flows coming into the bayou from the watershed, to understand the plan-form the
bayou needs to adjust to given a changing flow regime, and to understand the vertical gradient of the
thalweg, or profile, of the bayou bed for at least several bends of the bayou. For a bayou the size of
Buffalo Bayou downstream of the dams, any solutions to erosion reduction and property protection
need to be done in the context of
understanding several miles of the bayou in each direction of any single project.
6. The Memorial Park Demonstration Project is an effort initiated by and supported by the Bayou
Preservation Association to attempt to apply the best scientific stream restoration practices to a short
stretch of the bayou that has been changing rapidly and of which some of the banks had already been
armored with steel piles and rip-rap and bio-engineered terraces, resulting in rapid changes to the
opposite banks.
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7. The Demonstration Project is intended to show how property can be protected with due regard and
respect for the physics of river morphology. This is done by adjusting the plan shape of the stream to
correspond to the overall shape that the bayou is working to get to by chewing into the banks, but making
the adjustments in such a way that they don't endanger homes or other improvements along the way. By
making the adjustments at one time as a construction project, the massive amounts of material that the
bayou would otherwise chew out of the banks as erosion does not clog up downstream reaches of the
bayou. The bed of the bayou is also adjusted to correspond to the new plan-form, with deeper pools at the
outer bends and shallower riffles between the bends; this bed profile is important to match to the plan
shape of the bayou; otherwise the energy in the stream will work to create a riffle/pool sequence on its
own, but it might not initially match the plan shape and it might continue to try to change the plan shape,
causing more erosion.
8. This kind of stream restoration work attempts to use only the natural soils already in the bed of the stream
and only natural woody material along the outer bends and in the riffles, to help resist erosion right after
construction, to help roughen the bend so that the higher energy fast water is moved slightly away from the
soil surface of the bank, and, importantly, to enrich the riparian habitat for small fish, reptiles and benthic
creatures. Native trees and riparian vegetation is planted back along the banks, tight up against the outer
bends so the root systems help secure the bank and so the shade of the branches cools the pools, and
further back from the banks on the sandbar side of the bend so that high flows can pass across the bar
naturally.
9. The stream restoration work will be messy during construction, but if properly planted with native riparian
plants, the work area quickly recovers its lush riparian qualities, and provides better habitat than is
provided by a rapidly eroding and degraded stream system. This is something new for our region, and it is
why we are calling it a Demonstration Project. We need to examine the project closely, and we need to
make adjustments to it as it is underway if necessary, and we need to be sure that the project has
adequate follow-up to measure the success of the project from all standpoints; a reduction in erosion and
excessive sediment and turbidity in the bayou; re-growth of the riparian and upland native vegetation;
reestablishment of wildlife habitat, and improved water quality.
10. Although there are projects in the region that have used some of the principles of fluvial
geomorphology, and although they are very different projects, there are lessons from each that we should
learn from.
a. Sometime in the mid 1990's the footbridge on the north bank of Buffalo Bayou near Glenwood
Cemetery was in danger of washing out. An engineering firm replaced the wooden bridge with a
steel truss bridge, and re-established the bank of the bayou upstream and downstream of the
bridge using a toe of rip-rap and terraces of MSE (mechanically stabilized earth) walls. This is a
system of reinforcing the soils with geo-textiles and supporting the front face with a wire mesh (not
the same as gabion walls). The bayou bank looked very 'engineered' right after construction, but in
a few years, after silt had covered over the terraces and self-sown Green Ash and other trees grew
in the silt, and the bank looked completely natural. The lesson here is that that even with an
engineered system to protect a piece of infrastructure, and even with no deliberate re-vegetation,
nobody could tell that it was not a natural bank.
b. The Meyers Park project on Cypress Creek was the first project in the county to deliberately
re-establish a fluvial geomorphologically correct flood-bench and riffle/pool sequence to reduce
the heavy erosion that was occurring along the park. This project demonstrated the basic rule that
coastal streams like ours need to be able to flow out onto a flood-bench at the "channel-forming
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flow" which is about a two year storm. The flood benches were excavated, and ephemeral
wetlands were created along the benches. Riparian trees were planted along the banks and on
the flood benches. The initial work appeared very 'engineered', but the first phase is now
beginning to grow in, with the trees growing up and vegetation getting well established along the
banks. Although the HCFCD required the use of Bermuda grass to initially stabilize the channel,
the riparian vegetation has all but obliterated the Bermuda grass along the banks and the channel
is appearing more 'natural' with each passing year, but is now a stable channel without the
excessive use of concrete or steel.
c.
The Buffalo Bayou Park, between Sabine and Shepherd Streets, is currently under construction
and the nearly completed segments where the HCFCD contractor is working are only In their initial
post-construction condition. Fluvial geomorphologists were part of the Flood Control's design
team and care was taken to absolutely minimize the amount of new structures in the bayou
channel as they work to remove silt and to partially re-establish some of the historic bends of the
bayou. Here, as along Cypress Creek, the District required the use of Bermuda grass for the initial
erosion control and bank stabilization.
A large number of native riparian trees are being planted along the new banks such that there will
be an almost continuous canopy of trees along the bayou again. The surface of the ground will
receive additional tree and understory plantings as a part of the Buffalo Bayou Partnership part of
the project, and it is the intent of the design for the immediate banks of the bayou to NOT be
mowed on a regular basis (mowers will not fit between all the trees), but only to receive enough
vegetation management to restrict the amount of ragweed and invasive vegetation along the
banks.
Just upstream of Sabine Street, along the south bank, a pilot planting area was established a
year ago, with dozens of very small Cypress, Ash, Sycamore trees were planted, along with a
long list of native riparian understory vegetation. With only a year under our belt, and a very dry
hot year at that, it is still too early to know what we have learned from this planting, but we hope to
find out which native plants are most likely to thrive in these conditions and to provide a frame
work for a long-term healthy native riparian ecosystem.
11. The Memorial Park Demonstration Project wants to be different from these other projects; having learned
from them that the basic principles work as predicted by the science here with our climate, soils and
vegetation, we want the Demonstration Project to be a model of how to set the framework for the
restoration of a natural, and "wild and wooly" stream corridor. If the project is successful once it is
completed and allowed to mature, this kind of stream restoration might be an effective alternative to the
often not so effective structural solutions used as band-aids for individual property owners. We will need to
work with the HCFCD and their designers and contractors to build on their fluvial geomorphologic
foundation and "roughen" up the finish product with the creation of habitat structures, micro topographic
features, and more complex planting schemes. The BPA and the Memorial Park Conservancy might need
to help design and maybe even to help fund some of these additional ecosystem features.
12. A denial of the science of fluvial geomorphology, a denial of the unbreakable link between the
watershed and the bayou, a denial of the very real changes the bayou is going through right now,
and a denial of the very real urges and rights of property owners and government agencies to
protect their assets from losses due to an encroaching and eroding bayou .........
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... will condemn the bayou to walls of concrete, bags of cement, banks of concrete rubble and
steel sheet piles, each just making the problem worse for neighbors across the bayou, and for those
upstream and downstream, in an ever intensifying battle against the soul and spirit of Buffalo Bayou.
We HAVE to find the right tools so a natural Buffalo Bayou can co-exist with an increasingly urban
watershed and population! The Demonstration Project is just a step in that direction.
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13-1013
BBP
Letter of Support
14-0225
BPA
Letter of Support
14-0331
MPC
Letter of Support
14-0601
Steve Lindley
Informational
THE MEMORIAL PARK DEMONSTRATION PROJECT
A Project to repair, restore and reforest Buffalo Bayou
June 2014
Earlier this year, the Harris County Flood Control District (HCFCD) applied for a permit from the United States Army
Corps of Engineers (Corps) to allow for the work on an erosion control and restoration project known as the Memorial
Park Demonstration Project (MPDP). MPDP will restore an approximate length of 5,800 linear feet of Buffalo Bayou,
which primarily borders Memorial Park and the River Oaks Country Club, plus up to an additional 800 feet along the
Hogg Bird Sanctuary tributary. In this reach of the bayou, there are at least seven (7) significant areas of what is called
‘high bank failure’ (see Figure 1) – that is, where the bayou has completely eroded away the entire slope of the bayou
and related plant and shrub cover, including mature trees. These high bank failures have resulted in significant loss of
property and the ultimate deposition of sediments and debris downstream, a large part of which has to be dredged and
removed from the bayou and ship channel by HCFCD and the Port of Houston Authority (PHA). There is little
disagreement that Buffalo Bayou is under a great deal of stress. This stress is primarily caused by the continued
urbanization of the Buffalo Bayou Watershed, and the operational practices of the Corps, who manage the Addicks and
Barker reservoirs for flood damage reduction purposes, through the staged release of collected storm water from the
Addicks and Barker Reservoirs. Where disagreement has arisen on MPDP, centers on the proposed methods to stabilize
and restore the bayou and its banks.
FIGURE 1 – Seven highlighted areas of erosion along the proposed project area
The permitting process being conducted by the Corps, which began in early May, allows for a public comment period on
the project, through a Public Notice posted by the Corps. Since the public comment period began on May 1, there has
been an effort by a number of individuals and groups to discredit MPDP by using fear tactics and half-truths to make a
case that the MPDP is based on bad science and would destroy the bayou as we know it.
Facts around the Project:
The term ‘riparian forest’ is used a lot in the various commentaries and articles. So it is important to understand what a
‘riparian forest’ is. The United States Department of Agriculture (USDA) describes it is as the forest buffers that are
natural or re-established woodlands next to streams, lakes and wetlands. These buffers usually consist of trees, shrubs
and grass plantings that are managed to enhance and protect aquatic resources from adverse impacts from the
management of adjacent lands1. It should be noted that riparian forest does not mean a specific tree or shrub species,
but the area adjoining the stream or river, which in this case is along Buffalo Bayou.
Below are aerial photographs of the bayou in 1938 and more recently within the last year – see Figure 2 and 3. As can be
seen, the bayou was almost indistinguishable in 1938. Since that time, the buffer zone or riparian forest that runs
parallel to the bayou has continued to be destroyed (see photographs below), so that today there are few areas along
this reach of the bayou where the trees actually hang over the bayou and provide a closed tree canopy over the bayou.
Close-up aerial photographs of the bayou from this most recent aerial (Figure 4), shows us that many trees have fallen
into the bayou because of the erosion caused by the movement and expansion of the bayou’s streambed through the
stress being put on the bayou system as it tears itself apart in an effort to re-establish a state of balance with the
stresses it is encountering.
FIGURE 2 – 1938 Aerial image of the proposed project area
FIGURE 3 – 2012 Aerial image of the proposed project area
1
USDA National Agroforestry Center, ‘Working Trees Info – What is a riparian forest buffer?’, First Edition May 2012
FIGURE 4 – Aerial Images showing the mature trees that have fallen into the Bayou after a large rain event
High Bank Failure with significant mature tree, shrub and vegetation loss
High bank failure with tree, shrub and vegetation loss
Bank failure with tree and vegetation loss
What is causing this stress? As mentioned above, there are two primary causes for the deterioration of the bayou and its
streambed. First, there is the continuing urbanization of the Buffalo Bayou watershed area. Whereas in the past, the rain
water entering into the bayou might take several days to work its way into the bayou through undeveloped property
that allows for saturation of rain waters into the undeveloped landscape, today the water enters the bayou system
within minutes because of the addition of impervious cover within the watershed, such as roads, parking lots, buildings
and the associated man-made drainage systems. The impact of Houston’s development on the watershed can be seen
on the graph below, which is the reading of the maximum flow rate recorded annually at the Shepherd St. flood gauge Figure 5. While rain events vary from year to year, this graphically shows the continued increase in maximum flow rates
due to water entering the bayou faster after rain events. The second cause comes from the managed release of water
behind the Barker and Addicks reservoirs. Once water accumulates behind the two reservoirs, it is released at a rate of
2000 cfs (cubic feet per second). When water is being released at this rate, it has the effect of raising the bayou level in
Buffalo Bayou by approximately 6-8 feet. If this release is sustained for any period of time, the raised water levels
permeate the bayou banks. Once the lower levels of the banks are saturated with the higher water levels, instability is
created in the banks because of the shear stresses that are placed on the lower portions of the bayou’s slopes. These
stresses erode the base of the slopes and cause the slopes to collapse, undermining the ability for vegetation and trees
to survive on unstable slopes. This is graphically seen in the failures that are occurring in the high bank areas outlined in
Figure 1 and shown in the photographs. Once the vegetation is lost and the banks are exposed, the erosion from future
rain events accelerates and expands the loss of land and property in these high banks areas since there is no vegetation
or root systems in place to help stabilize the slopes. The rate at which this is happening is alarmingly high. The River
Oaks Country Club, for example, has lost from 10-20 feet of property over the past 8-10 years on the western part of its
property near the upper end on the project reach. Doing nothing to help prevent the loss of land is not an option.
FIGURE 5 – Historical Annual Peak Flow Rate as recorded at the Shepherd Drive USDS gage
One of the concerns raised by MPDP opponents is that there will be significant ‘clear cutting’ of the riparian forest.
Before addressing the potential loss of some trees, HCFCD had an independent third party perform a vegetation survey
along the reach of the project. Within this survey, two areas were covered. First was the area within the proposed final
easement of the MPDP and the second area was a 20 foot buffer area just outside of the easement but running parallel
to the easement. Within this area, trees that were 8” and greater in diameter were captured by GPS units providing x, y,
and z spatial locations. Other information captured for these trees included the condition index, crown diameter,
species type, and any noteworthy features about the tree. See Figure 6 of a pictorial of the surveyed trees. There were
972 trees inventoried within and 20 feet beyond the easement. Of these trees, there are 73 dead trees and 899 living
trees. The top 4 species found in this area are: Boxelder (220), American Sycamore (115), American Elm (102) and Cherry
Laurel (78). These four species represent 515 or 57% of the live trees which are 8” or greater in diameter. As to the
quality and condition of the trees, only 225 trees are rated as being in “Good” or “Excellent” condition, which is 25% of
the live trees. See Figure 7 for additional tree inventory information. However, when considering any potential loss of
trees in this project, it needs to be remembered that MPDP can only be worked within the easement and that just
because there is an easement doesn’t mean that work will be performed from easement line to easement line. In fact,
there are large areas within the easement that will not be disturbed – see Figure 8.
FIGURE 6 – Surveyed trees 8” in diameter or larger within the Easement Area plus a 20’ buffer.
Note: This is not a listing or pictorial of the trees that will be removed in the project
600
Trees by Condition Index
489
Number of Trees
500
400
300
223
185
200
100
73
2
0
Dead
Poor
Fair
Good
Excellent
Tree Condition Index
FIGURE 7 – Number of trees surveyed within the final proposed project area easement shown by condition index
FIGURE 8 – Limits of the area proposed for active restoration in comparison to the location of trees surveyed
When considering the potential loss of any trees, one must consider the area within the easement where ‘cut and fill’
work will be done. In the tree inventory, there are 568 trees or about 63% that are located outside the proposed ‘cut
and fill’ lines; thus, only 331 tress (or about 37%) are potentially impacted, some of which are already dead. It should
also be noted that within the survey area there are no cypress or magnolia trees (which are native to the bayou) since
they were historically harvested for their lumber value during the early days of the Houston area’s development. MPDP
proposes to re-vegetate the project area with a much more diverse pallet of native vegetation, and to plant at least 4
times as many trees as would be potentially affected.
Summary
The Memorial Park Demonstration Project is designed to showcase a holistic, proven stream restoration and bank
stabilization technique to enhance the ability of Buffalo Bayou to transport storm water efficiently, stabilize the banks of
the bayou, and reduce the transportation of sediment downstream. Short term fixes in only certain spots is not the
holistic approach of MPDP. While some may disagree with MPDP because it is not limited to spot repairs of eroded
areas, it has been designed using sound scientific data and proven engineering techniques that have been successfully
used in many other parts of the country and the world.
MPDP is also distinctly different than the project conducted by the Houston County Club that was designed with the
objectives of stabilizing one side of the bayou’s bank and providing for an increase in aesthetic appeal. MPDP looks to
address both sides of the bayou’s banks as they work in unison with each other.
The completed project will result in improved water quality and natural habitat along this stretch of the bayou. Will the
growth of vegetation and restoration of a diverse habitat be immediate? No. But this is a collaborative undertaking with
a long-term vision for what Buffalo Bayou could once again become: a sustainable, natural bayou system with a diverse
setting full of native vegetation and habitat. While there will be some tree and shrub removal along parts of the project
reach, this removal will be mitigated by the reforestation and planting of more native trees and shrubs than were
removed, which will re-establish the proper plant community appropriate for Buffalo Bayou. In short, while MPDP can
only focus on the problems encountered within the proposed project reach, and not the entire Buffalo Bayou
watershed, it is an appropriate and best response to the bayou’s stress. Taking no action at all is not an acceptable
approach to reducing further loss of property and habitat, and improving water quality.
Quick Facts:
Project Manager: Harris County Flood Control District
Project Engineers: KBR and StanTec
General Contractor (CMAR): SpawGlass Civil
Environmental Sub-contractor: Shamrock Environmental
Project Partners: Harris County Flood Control District, City of Houston and River Oaks Country Club
Supporting Entities: Bayou Preservation Association, Buffalo Bayou Partnership, Memorial Park Conservancy
Project Length: Approximately 5,800 feet on Buffalo Bayou and up to an additional 800 feet within the Hogg Bird
Sanctuary
Type of Design: Natural Channel Design originally pioneered by Dave Rosgen
Cost: Estimated to be $6.0 million
Websites for Additional Information
Harris County Flood Control District - http://www.hcfcd.org/P_memorial/
Bayou Preservation Association - http://www.bayoupreservation.org/
Attachments:
A - Fact Sheet from Harris Country Flood Control District on the Project
B - Memo from Kevin Stanley of the Bayou Preservation Association regarding the Project
C - Letters from the Bayou Preservation Association regarding the Project
D - Letter from the Buffalo Bayou Partnership regarding the Project
E – Letter from the Memorial Park Conservancy regarding the Project
14-0605
Terri Thomas
MPDP Support Letter
Thursday, June 5, 2014
Dear Bayou Friends,
I want you to know my husband and I are homeowners within the reach of the Memorial Park
Demonstration Project (“MPDP”), and we support the project completely.
Living on the bayou, we have seen and continue to see serious erosion taking place. The
silt-laden water is ugly and unhealthy. We believe the benefits of a full reach of natural erosion control far
outweigh the construction mess proposed. Some factual information about the project is attached.* This
information is unlike the comments I have been reading or hearing from a few. As an example of the type
of bio-engineering work that has been proposed, please look at the following five photos which I hope
will help to paint a picture of how the MPDP will protect Memorial Park (“MP”), the Bird Sanctuary,
River Oaks Country Club (“ROCC”), and the homes along the bayou, as well as improve the water
quality and storm water flow of the bayou. Simply planting trees will not work.
Photo A - Oct. 2006
Photo B - Oct. 2006
Photos A & B: This is the erosion that was taking
place at our home in 2006, also affecting our
neighbors’ land. You will notice all the trees which
came down with the erosion.
Photo C: This is a picture of our bio-engineering
work in process. Please notice the destruction to the
shoreline which had to take place first to stabilize
our shoreline. We used rock at the toe and a bioengineered stair step with native materials, planting
many native trees and plants between the steps.
Photo C - Mar. 2008
Photo D - May 2014
Photos D & E: These are pictures of the same
shoreline from Photos A, B, and C. Six years later,
the trees are in place and growing strongly. In
Photo E you may even be able to see the silt/sand
from the May 28, 2014 flood collecting around the
grasses and trees.
At the time we were doing our bio-engineering
control work, I requested Flood Control (“FC”)
to take part in the project and go around their
easement on Mimosa Point. Mike Talbott, Director,
Harris County Flood Control District, told me
they could not do it for me without helping every
other homeowner on the bayou with their bandaid approach. I told him that I understood, was
disappointed, and I would be back. I am back as a
strong supporter of the MPDP, a project which will
address both sides of the bayou for about a mile.
Dr. Dave Rosgen has developed a natural waterway
design for erosion control. I have studied his design,
and support it tremendously. I am working with FC
to make sure the project is done the best it can be.
This region now has the opportunity to do a small
complete reach of Buffalo Bayou with this natural
erosion design. Buffalo Bayou is a distressed
natural waterway. Please take the time to read
the factual information about this project!* The
Tree Inventory which you may read on the Flood
Control website is very informative. It is not an old
growth riparian forest which is being destroyed.
Yes, go down to the bayou with a plant person and
check out what the vegetation by the bayou really
is presently.
Photo E - May 2014
I hope you will share this letter with your friends
and colleagues. I hope some people will consider
writing a letter of support to the Corps of Engineers
for this fabulous public/private partnership project.
All of the public agencies are getting to a financial
point that they must partner with private money
in order to get projects done. People who love
Memorial Park should be thanking ROCC for their
willingness to help the park as well as their own
golf course. Believe me, if this project is stopped,
ROCC will do their own erosion control. Who
will help Memorial Park and the Bird Sanctuary
then? One of our neighbors has been attempting to
get something done to the drainage outfall within
the Bird Sanctuary for 14 years. No governmental
agency would take the responsibility to pay for
the needed repair. This MPDP will finally address
the erosion of the Bird Sanctuary from this badly
installed drainage outfall without cutting many
trees down, but instead building up to the tall
slopes with the steps of soil, with native trees and
plants planted between the steps.
Terri Thomas - 6 Rains Way
h: 713-861-1408 cell: 713-807-1902
email: [email protected]
14-0616
BPA – USACE Letter
Board Members
Terry Hershey, Founder
Executive Committee
Robert Rayburn, President, Community Volunteer
J. Tynan Kelly, Past President, Attorney
Bruce Heiberg, VP, Signal Creek Architects
Jack Sakolosky, VP Community Volunteer
Linda Shead, VP, Shead Conservation Solutions
Janet K. Wagner, Secretary, J.K. Wagner & Co.
Michael Hendryx, Treasurer, Strong Pipkin Bissell & Ledyard
Chris Browne, Director, EHRA
Elaine Finger, Director, Community Volunteer
Jim Robertson, Director, Community Volunteer
Frank C. Smith, Jr., Historian, Community Volunteer
Elle Anderson, Grounds Anderson, LLC
Hugh J. Barrett, Strategic Alliance Group
Dr. Tom Biggs, Community Volunteer
Michael F. Bloom, R.G. Miller Engineers, Inc.
Jill Boullion, Greens Bayou Corridor Coalition
Dick Cate, MCCM Architects
Claire Caudill, Community Volunteer
Allen B. Craig, Gardere, Wynne, Sewell
Lee Forbes, Forbes Consultancy, PLLC
Joanna Friesen, Community Volunteer
Mike Garver, BRH-Garver Construction, L.P.
Deborah Hartman, Deborah Hartman PR
Colleen Holthouse, Community Volunteer
Mike Howell, Howell Law Firm
Lynne B. Johnson, Community Volunteer
Tom Kartrude, Armand Bayou Nature Center
Robert S. Lee, GSI Environmental Inc.
Betty Leite, KBR
Jennifer Lorenz, Bayou Land Conservancy
Judy Meyer, John Daugherty Realtors
Mike Mize, Community Volunteer
Rebecca Olive, AECOM
Bob Schwartz, Community Volunteer
Lawrence Spence, Westside High School, HISD
Cory Stull, Freese and Nichols, Inc.
Merrie Talley, Talley Landscape Architects, Inc.
Terri Thomas, Community Volunteer
Matthew K. Zeve, IEA, Inc.
Advisory Board
Glenda Barrett, Community Volunteer
John R. Bartos, Houston Canoe Club
Judy Boyce, Jacob and Terese Hershey Foundation
Jacqueline Buskop, Community Volunteer
Glenda Callaway, Ekistics Corporation
Mary Carter, Blackburn & Carter
Karen Cornelius, Community Volunteer
Tom Douglas, Community Volunteer
Clayton Erikson, Community Volunteer
Erik Eriksson, Port Of Houston Authority
JoAnne Graham, Community Volunteer
Don Greene, Whitewater Experience
Susan Hill, Hawes Hill & Assoc.
Tom Ivy, Community Volunteer
John Jacob, Texas A&M
Carla Knobloch, Community Volunteer
Harriet Latimer, Development Consultant
Jim Lester, Houston Advanced Research Center
Carl Masterson, Community Volunteer
Alisa Max, HC Watershed Protection Group
Mickey Merritt, Texas Forest Service
S. Reed Morian, DX Service Co.
Paul Nelson, Lone Star Groundwater Conservation District
Roksan Okan-Vick, Houston Parks Board
Kathleen Ownby, SPARK School Park Program
Mary Anne Piacentini, Katy Prairie Conservancy
Rachel Powers, CEC
Jim Pulliam, North Harris Co. Regional Water Auth.
Commissioner Steve Radack, Harris County
Todd Running, Houston-Galveston Area Council
Kevin Shanley, The SWA Group
Dick Smith, Cypress Creek Flood Control Coalition
Melvin Spinks, CivilTech Engineering, Inc.
Art Storey, HC Public Infrastructure Dept.
Gary Struzick, Klotz Associates, Inc.
Mike Talbott, HC Flood Control District
Brittany Tones, Terracon
Rico Torres, Bayou Shuttle Service LLC
MaryAlice Torres-MacDonald, Texas Tech University
Len Waterworth, Community Volunteer
Carolyn White, HC Flood Control District
Carla Wyatt, HC Flood Control District
Watershed Representatives
Tom Kartrude, Armand Bayou
Bob Schwartz, Brays Bayou
Mike Garver/ Anne Olson, Buffalo Bayou
Linda Jones, Cedar Bayou
Mike Mize, Clear Creek
Jim Robertson, Cypress Creek
Charriss York, Dickinson Bayou
Jill Boullion, Greens Bayou
Merrie Talley, Hunting Bayou
Eileen Hatcher, Japhet Creek
Becky Houston, Little White Oak Bayou
Joanna Friesen/ Amy Sullivan, Sims Bayou
Jennifer Lorenz, Spring Creek
Tom Gall/ Bob Lee, White Oak Bayou
June 16, 2014
Mr. Dwayne Johnson
Regulatory Branch, CESWG-PE-RB
U.S. Army Corps of Engineers
P.O. Box 1229
Galveston, Texas 77553-1229
[email protected]
Dear Mr. Johnson,
The Bayou Preservation Association (BPA) submits this letter in support of the
application of the Harris County Flood Control District (HCFCD) for approval of the
Memorial Park Demonstration Project, USACE Permit Number: SWG-2012-01007.
SUMMARY OF BPA COMMENT AND POSITION
The BPA was founded in 1966, initially in opposition to a Corps of Engineers project to
rectify Buffalo Bayou (Bayou) and line it with concrete. This opposition succeeded
because of the tenacious efforts of BPA founders Terry Hershey and George Mitchell,
and the intervention in Congress of then Congressman George H. W. Bush. Since that
time, BPA has taken on the more general mission: “to protect and restore the richness
and diversity of [Houston area] waterways through activism, advocacy, collaboration
and education.”
The BPA supports the permit application because it promises to serve the twin BPA
goals of protection and restoration of Houston’s bayous. BPA considers the Memorial
Park Demonstration Project (“Demonstration Project” or “Project”) to be particularly
worthy of support because it is the first project of the Harris County Flood Control
District (HCFCD) to incorporate fully the insights and principles of Natural Channel
Design (NCD). For this reason, the Demonstration Project fulfils a long term interest
and goal of the BPA and one of its founding directors, Terry Hershey, to test and
demonstrate the benefits of NCD stream restoration techniques in the Houston
environment. BPA’s support is not unconditional, however. Rather BPA welcomes
careful public scrutiny of the Project and Project plan, and takes seriously all comments
on the Project plan and design. BPA reserves the right to withdraw its support for the
Project if evidence shows that the Project design and implementation departs
substantially from NCD principles or if the Project cannot fulfil its protective and
restoration goals and purposes.
The Demonstration Project has engendered some criticism and controversy. This is
understandable because the earthmoving aspects of construction are directly
observable and appear destructive, however are necessary to correct the configuration
of the channel so that it can be stable and support quality habitat. Also, waiting for the
replanting and regrowth of vegetation to mature to high quality habitat takes significant
time in human time scales. Erosion is highly destructive of trees and habitat, but
operates on longer, gradual time scales, so the destruction goes unnoticed. The
hydrology causing the erosion is very powerful and is not of natural origin but is rather
the unintended product of urbanization and efforts to control flooding.
Katharine C. Lord, Executive Director
P.O. Box 131563 - Houston, TX 77219-1563 - Phone: 713.529.6443 - Fax: 713.529.6481 - email: [email protected]
www.bayoupreservation.org
Bayou Preservation Association
SWG-2012-01007
June 16, 2014
The destructive character of Buffalo Bayou’s unnatural hydrology can be seen in a series of aerial photographs
going back to 1944 that are available on Google Earth. Attached are some of these photos plus a 1930 photo.
The Public Notice states that the channel has moved three hundred fifty (350) feet since 1995 and destroyed
more than an acre of land. However, the aerial photographs show that this migration of the channel has
destroyed an entire oxbow of the Bayou, eliminating a much larger riparian forest. The images show also that
the canopy of trees that covered Buffalo Bayou in 1930, 1944 and 1953 has disappeared as erosion has
widened the channel. For BPA, evaluation of the Demonstration Project cannot and should not be framed as a
simple comparison of the temporary effects of construction on trees, vegetation and habitat in the limited
Project area. The proper frame of reference, rather, is to view the short-term negative effects of Project
construction, which will be followed by replanting and regrowth, against the long-term benefits of eliminating
the ongoing destruction to forest and habitat that will continue to occur if the proposed stream restoration
project is not implemented.
The processes and damage documented by the time series of aerial imagery is confirmed by what one sees
on a canoe or kayak trip down the Bayou. All up and down the Bayou property owners have sought to armor
their own stretch of bayou frontage with steel sheet piles, bags of concrete, timber walls, gabions, and giant
heaps of rubble. This is understandable because people do what they think they need to do to protect their
property. The problem with these fragmentary, band-aid solutions is that some hold up, at least for a time, but
most fail, resulting in accelerated erosion and habitat degradation. Moreover, even when successful, one
property owner’s solution simply shifts the energy of the Bayou to the opposite bank or to the downstream
properties. The Public Notice notes that the bayou groups, including BPA and landowners that have
encouraged HCFCD to do the Project, believe that amelioration of the damage to the Bayou and restoration to
a more nearly natural and stable configuration requires a holistic approach to the Bayou channel and not
piecemeal armoring.
The Demonstration Project is intended to show how the channel of the Bayou can be stabilized to reduce
erosion and protect property by showing due regard for, and making use of, the physics of river morphology.
To accomplish this goal, the work to be performed will: 1) narrow and deepen the Bayou to a more stable,
natural form; 2) re-align the channel to a stable, meandering plan form; 3) re-establish an adequately-wide
floodplain down at the level of the Bayou banks; 4) incorporate natural bank stabilization components on the
restored Bayou; and 5) re-vegetate the entire riparian corridor with native grasses, shrubs, and trees. River
science is sufficiently advanced to allow hydrologists and engineers to identify the overall shape and
configuration that the Bayou is working to achieve as it chews chaotically into the banks. In accordance with
NCD principles, the Demonstration Project design will, indeed, re-sculpt the banks and central channel to
achieve a plan-shape of the stream to allow the flow dynamics to promote and sustain a stable equilibrium
consistent with the equilibrium the Bayou would itself achieve in geological time if left otherwise undisturbed.
By making the adjustments at one time as a construction project, the transition will reduce endangerment of
homes or other improvements along the way, and reduce the massive sediment loads the Bayou is presently
carrying away from the banks as erosion.
There is no question that the stream restoration work will be messy during construction. It is an exaggeration,
however, to characterize the process of construction as a simple bulldozing of the riparian areas. This kind of
stream restoration work attempts to use only the natural soils already in the bed of the stream. Structural
support does not come from industrial materials, but from natural woody material along the outer bends and in
the riffles, to help resist erosion right after construction, to help roughen the bend so that the higher energy,
fast water is moved slightly away from the soil surface of the bank, and, importantly, to enrich the riparian
habitat for small fish, reptiles and benthic creatures. Native trees and riparian vegetation are planted back
along the banks, tight up against the outer bends so the root systems help secure the bank and so the shade
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of the branches cools the pools, and planted further back from the banks on the sandbar side of the bend so
that high flows can pass across the bar naturally. The Project contemplates re-planting of the Project area with
native riparian plants and replacement of collected and stockpiled existing topsoil to support further the
restoration process. If done properly, the Project area will quickly recover its lush riparian qualities, and will
provide better habitat than is presently provided by a rapidly eroding and degraded stream system.
BPA INTEREST AND ROLE IN THE DEMONSTRATION PROJECT
BPA has been a supporter and catalyst in the origination and development of the Project. Over her many
years of environmental activism, BPA founding director Terry Hershey became familiar with the work of Dr.
Dave Rosgen, a hydrologist who developed Natural Channel Design. The Hershey Foundation has provided
support for many years to BPA personnel and others to attend seminars conducted by Dr. Rosgen on NCD
and related subjects. Ms. Hershey wished to apply Dr. Rosgen’s methods in Houston and made a restricted
grant of funds to BPA that limited use of funds to “bayou protection or rectification in a manner demonstrated
or recommended … by David Rosgen.” BPA used the grant to organize in November 2010 a workshop
conducted by Dr. Rosgen. The Public Notice refers to this workshop as a beginning of Project planning, and
further documents thirty-three (33) additional meetings and two (2) public hearings on the Project, many of
which were organized or attended by BPA representatives.
THE MORPHOLOGY OF BUFFALO BAYOU
Natural Channel Design is a product of the scientific discipline of fluvial geomorphology. NCD is an evidencebased discipline that seeks to apply the insights of fluvial geomorphology to the improvement and restoration
of streams that have been adversely affected by human influences and intervention. It is based on a stream
classification system developed by Dr. Rosgen, and an understanding of these stream types and forms and
their respective and relative stability or instability in nature. NCD stream restoration projects involve sculpting
stream banks and channels and re-establishing an adequate floodplain at the level of stream so that the
hydrological forces of the stream will promote the stability of the stream’s channel and banks to reduce erosion.
Done properly, NCD stream restoration improves water quality and clarity, and improves habitat for aquatic
species. NCD also emphasizes the planting of appropriate vegetation in riparian areas to promote bank
stability and natural beauty.
PROJECT NECESSITY
The essential problem with Buffalo Bayou is the urbanization of the watershed that drains to it and the
operation of the Addicks and Barker Reservoirs, both of which have dramatically altered the hydrologic
conditions, referred to as “hydromodification,” that the Bayou has to exist in. Urbanization has utterly changed
the response of the Buffalo Bayou watershed to rainfall events. In the language of river science, the speed
with which rainfall in the watershed reaches the stream channel is called “time of concentration.” Today, the
time of concentration for rainfall in the watershed below the Addicks and Barker Reservoirs is very rapid, and
the Bayou exhibits rapid, flashy peak flows within a few hours after a storm event. By contrast, Buffalo
Bayou’s channel configuration evolved in pre-development conditions in which the Bayou’s response to rainfall
events was measured in days and weeks. With urbanization, the time of concentration of rainwater in
Houston’s bayous is in most situations much faster than it was in natural conditions. In the upper Buffalo
Bayou watershed, the time of concentration is much slower or non existent when held back by dams; however
when later released from the dams, these flows impact the bayou downstream in a detrimental manner as
described in the following paragraph. The rapid time of concentration follows directly from the replacement of
grass and trees with roofs and pavement, and also traditional civil engineering which focused on the
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installation of systems in urban areas intended to speed drainage. These changes have not merely caused a
more rapid rise and fall inside the bayou channels; this also means that the more rapid concentration of storm
water in Houston area bayous have higher peak flows– meaning higher floods.
The flooding effects of urbanization are buffered somewhat in the Buffalo Bayou watershed because the
Addicks and Barker Dams limit peak flow, but the pattern of rapidly rising flash-type storm drainage followed by
rapid drops is well established. Moreover, the flow regime associated with USACE management of stormwater
releases from the Addicks and Barker Reservoirs also contributes to further erosion by repeatedly inundating
the bases or “toes” of the banks, limiting the ability of vegetation to become established at the interface of bank
and channel. Well rooted vegetation at the toe promotes bank stability, but the cycle of rapid inundation and
drying interferes, eventually leading to collapsing banks in many locations in Memorial Park. While observing
the erosive nature of the stormwater releases from the Dams, we acknowledge that these controlled
stormwater releases provide important flood protection. Implementation of this Project will allow this portion of
the Bayou to adjust to the unfortunate and unintended side effects of these flood control devices.
The key to a stable channel is connection of the channel to an adequate floodplain. In stable streams, at the
critical depth where the banks would begin to fail, referred to as the “bankfull” depth, the stream flows have
access to a floodplain where they spread out, reducing the velocities and eliminating any increase in depth in
the channel flows. When the volumes and timing of flows change substantially, as has happened in Buffalo
Bayou, a process called “downcutting” begins. As the depth in a stream increases, so do the shear stresses
acting on the channel walls. If the channel becomes too deep, the maximum shear stresses (a function of
depth, velocity and slope) on the channel bank toe will exceed the resistive capacity of the bank materials,
causing toe erosion and leading to bank failure. In response to these alterations, Buffalo Bayou has eroded
downward and outward and shifted its alignment in an attempt to create a new, stable stream and floodplain
system. The stream is trying to find a new equilibrium with a stable channel and a sufficient floodplain to
relieve erosive forces in the channel at high flows.
A well-documented model of channel
response
to
hydromodification
was
developed by Simon (1989) and is shown in
Figure 1 (taken from the Federal
Interagency Stream Restoration Working
Group [FISRWG] 1998). Simon’s model
was derived by studying stable streams that
were channelized and oversized for
drainage and flood control purposes and
streams that were subjected to major
hydromodification, such as Buffalo Bayou.
In response to this hydromodification, six
process-oriented stages of morphologic
adjustment were observed. Driven by the
natural tendency to re-establish dynamic
equilibrium by the geomorphic processes,
the streams downcut, widen, and then build
a new stable channel with a bankfull
floodplain bench at a new lower elevation.
Data collected during the NCD assessment
of the Project reach of Buffalo Bayou
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Figure 1: Simon’s Model of Channel Response to
Hydromodification
Bayou Preservation Association
SWG-2012-01007
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indicates that the channel is in the Class IV (degradation/downcutting and widening) and Class V
(aggradation/silting and widening) response stages at various locations along the Project reach. The goal is to
get Buffalo Bayou to a new equilibrium with a sufficient floodplain, as represented by the Class VI (quasi
equilibrium).
One approach to the problem might be to let the Bayou progress to its new equilibrium (Class VI) on its own.
The problem with that approach is that much of the channel and the riparian trees and vegetation will be
destroyed in the process, along with the loss of valuable real estate, and excessive sediment loads to the
bayou during the process. Further, the re-stabilization following Simon’s model in urban settings would take
decades or centuries (consider that channel-forming/bankfull flows only occur 6 to 8 times per year in Houston).
Some Project opponents propose that it is enough simply to add vegetation in the riparian corridor and apply
bio-engineering techniques to the failing stream banks. This approach is merely a “green” approach to channel
armoring, which has been shown to be ineffective at numerous properties along the bayou, as described
above.
The problem with armoring approaches is they do not reduce the erosive hydraulic energies in the stream that
are causing the failures; they simply try to armor the banks against erosion, which is doomed to failure.
Looking at Simon’s model (Figure 1), one can see that the initial problem occurs when the stream downcuts
and loses its connection with an adequate floodplain at its natural, stable point, which is referred to as the
“bankfull” channel elevation.
The key component to channel stability of a channel in Class IV and V response stages is not addressed by
any stand-alone form of channel armoring, bio-engineering, or vegetative plantings. Simon’s model shows that
once a stream has downcut and lost access to its floodplain, it will continue downcutting, degrading, and
aggrading until the point at which it can form a new, adequate floodplain at a lower elevation in the landscape,
which will then allow for the stream to stabilize. The goal of the Project is to skip the random and lengthy
destructive steps of the channel response process and to restore the channel to a new, stable stream channel
and floodplain that is in equilibrium with current watershed conditions through a single, fully-restorative step.
THE CHANNEL OF BUFFALO BAYOU IN THE VICINITY OF MEMORIAL PARK HAS BECOME WIDER
AND STRAIGHTER OVER TIME
Any member of the public who wants to see the dramatic changes in the Buffalo Bayou channel between
Memorial Park and the River Oaks Country Club (ROCC) should examine the time series of aerial photos of
the channel available on Google Earth. Attached are some of these photos. These sets of images are
available from 1944 to February of this year. A photo from 1930 is also attached. Comparison of these
images over time shows very dramatic erosion and changes of channel configuration as the Bayou is
progressing through the steps of channel response to hydromodification described by Simon (Figure 1), as
discussed above.
The following discussion addresses two particular locations. First is a forested location between River Oaks
Country Club, the Bayou channel and Memorial Park that has essentially disappeared, destroying acres of
forest. Second is a location at the Hogg Bird Sanctuary at the downstream end of the Project zone where the
changing dynamics of the Bayou appear to be leading to potential loss of a portion of the Hogg Bird Sanctuary.
The Disappearing “S”. The Google Earth aerial images of the Project area have images from 1944, 1953,
1978, 1989, 1991, 1995 and numerous sets at shorter intervals from 2002 to the present. The early images
(1930, 1944, 1953 and 1978) show a substantial forested tract of land between the River Oaks Golf Course
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and the Buffalo Bayou channel in the vicinity of the Parks Department maintenance facilities in the eastern part
of Memorial Park and the park boundary at Crestwood Street. The Bayou channel in the 1944 and 1953
image sets show a gently curving “S” shape defining a pair of oxbows. At the southerly curve of the “S” the
bayou flows in an east-southeasterly direction adjacent to ROCC, then makes a wide loop to flow in a nearly
opposite northwesterly direction, then completes the top of the “S” with a wide loop to flow east again. From
the top of the “S,” the channel curves gently to a southeasterly flow along Crestwood Street.
In these early images, the land on the ROCC side in the oxbow has the appearance of a heavily wooded
“peninsula" buffering the ROCC and Memorial Park. This “peninsula” in the top of the “S” remains largely
intact from 1930 to 2002, but gradual erosion is apparent. Accompanying this erosion is a consistent widening
of the channel as the years pass. A riparian canopy of forest foliage covers most of the bayou channel in the
1930, 1944 and 1953 images, but has mainly disappeared since then. The shape of this “peninsula” remains
recognizable into the 2000s, but the 1995 images are the last in which the tip remains forested. In the 2002
images, the tip of the former “peninsula” between the ROCC, the Bayou and Memorial Park has been shaven
down considerably, and the trees at what remains of the tip of the “peninsula” have largely disappeared. What
appears in its place in the 2002 image is a much wider channel, ponding zone and shallows where the curve of
the upper part of the “S” was in 1944.
The pattern of erosion, loss of riparian canopy and widening of the Bayou channel is evident in the 1944-1995
period, but gradual. Since 1995, the erosion of the former “peninsula” seems to have sped up, and the upper
part of the “S” has completely disappeared. In images made between 2002 and 2008, the “peninsula”
continues its retreat, but by 2008 sediment has accreted and filled the 1944 and 1953 channel. Images taken
in 2014 show that the land that was once a large, wooded “peninsula” on the ROCC side is now an alluvial
grassland on the Memorial Park side of Buffalo Bayou. The whole loop that defined the upper part of the “S” is
now essentially a straight line flowing almost due north and then bends sharply back to follow the curve along
Crestwood Street.
This detailed discussion is useful because the part of the Project Plan that has generated the most controversy
provides for cutting a curved channel through this angle and reconfiguring the south bank into an “S” shape
again. If the 1944 Bayou looked like a capital “S” from the air, then after Project completion, this part of the
bayou will look like a hybrid, slightly tilted “S” that is a capital letter at the bottom, and a small “s” at that top. It
is very understandable that this kind of geoengineering is jarring to a casual, nature-loving observer. If one
canoes the Bayou today, the narrow strip of land that remains has shrubbery and trees and looks nice. The
alluvial grassland is also nice and green. However, on the Memorial Park side just past the newly formed bend,
there is a nearly vertical, highly eroded bank that is on the receiving end of the strong currents that continue to
erode the channel and banks. This bank on the Memorial Park side will continue to erode very rapidly under
current conditions as the Bayou progresses through down cutting, degradation, and aggradation as it tries to
achieve a new equilibrium, as discussed above. Moreover, the hydrological forces that have destroyed the
upper half of the “S” are unchanged. By a chaotic process of uncertain duration, Buffalo Bayou will erode
away all that remains of the former oxbow. The channel realignment that some object to will remove a portion
of the remaining buffer, but in a way that stabilizes the channel to reduce the erosive forces.
The Bayou Channel Appears Poised to Claim a Substantial Portion of the Hogg Bird Sanctuary.
Examination of the Google Earth images shows that the Buffalo Bayou channel is very close to destroying a
portion of the Hogg Bird Sanctuary. In contrast to the relatively long-term (human time scale, instantaneous in
geological time frames) destruction of the big “S” described above, the Bayou channel appears ready to jump
north and claim the channel of a small tributary in the Hogg Bird Sanctuary. This risk is quite apparent in the
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most recent aerial images taken in February, 2014, where the barrier between the main channel and the
tributary is almost gone.
IMPACT OF PROJECT ON TREES AND UNDERSTORY
As noted above, some commentary from Project opponents suggests that the intention of the Project planners
is to “bulldoze” the banks of the Bayou in the Project area. This suggests that all trees in the Project area will
be destroyed. This is untrue.
The danger of tree removal is in the “cut and fill” zones. These are the areas where banks will be re-shaped to
a stable stream form with an adequate floodplain bench. The planners of the Project have advised BPA that
972 trees were identified in the Project area: 73 dead and 899 living, 391 on public property and 581 on private
property.
The “cut and fill” zones are approximately 30% of the total reach of the Project, placing approximately 180
living trees at risk of removal. BPA has been advised by the Project planners that no general clear-cutting of
these trees is planned. The intent is rather to assess each tree on a case by case basis during construction
with a view to the quality of each individual tree and how each fits into the plan of replanting. This assessment
involves issues such as whether an individual tree is a native or invasive, exotic species, how it contributes to
forest canopy, the health of the tree and its location. It is well to note also that the largest number of trees at
risk are on the portion of River Oaks Country Club property that has already been severely eroded as
discussed above and continues to be subject to the most severe erosive forces in the whole Project area.
COMMENTS ON PUBLICITY CONCERNING THE PROJECT
As planning and design work on the Project has progressed, the Project has been the subject of increasing
public comment. Public concern is natural and to be expected. BPA was founded as an ad hoc group
opposing plans to concrete line Buffalo Bayou. Traditional civil engineering approaches to flooding and
drainage issues were focused on speeding drainage, which meant straightening bayous and transforming the
natural channels into concrete ditches. In the decades since the formation of the Harris County Flood Control
District in 1935 and the major infrastructure construction projects of the USACE in the 1940s and 1950s,
flooding solutions based on the use of concrete, levees and rectification have lost favor with both the public
and the civil engineering community. The research and work of river scientists such as Dr. Dave Rosgen have
brought a deeper understanding of the risks and unintended consequences associated with interventions in
river systems, and the changes to river hydrology and dynamics resulting from long term human influences
associated with urbanization, deforestation, grassland destruction and the like. Gains in scientific knowledge
and increasing public appreciation of the beauty and importance of natural streams, associated riparian
greenspaces and wildlife habitat have placed a heavy burden on any project involving substantial earthmoving
and construction.
A key issue in evaluation of the Project involves one’s initial understanding of whether the reaches of Buffalo
Bayou in the Project are in a “natural” condition. What is or isn’t “natural” means different things to different
people. Additional differences of opinion may arise based on whether specific attributes of the natural
environment are viewed up close or from a broader perspective. If one’s preferred rule of the protection of
nature in the project area says that not a single tree may be removed, nor should a single shovel be permitted
to dig in riparian areas, then nothing smacking of engineering is permissible. If consistently applied, the
naturalist following such a rule may be compelled to classify the changes in Buffalo Bayou’s channel that have
occurred as a result of urbanization as “natural” as well, since the hydrological forces causing the changes are
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largely impersonal and not the product of human intention, though caused by human urbanization of the
watershed. As discussed above, the effects of urbanization have produced an unnatural flow of water. The
Bayou will adjust to these changes and become stable over a long period of time as discussed above.
Some project opponents point out recent re-growth of trees and riparian vegetation along eroded stretches of
the Bayou. This vegetation is dominated by fast-growing, opportunistic and emergent species (including some
invasive, exotic species). These should not be confused with the slow-growing species associated with a
stable floodplain and riparian corridor. In fact, many of these opportunistic and emergent species prevent the
growth of the more suitable and desirable species.
The BPA approaches the issues surrounding the Project from the standpoint of stewardship of the portions of
environment entrusted to Houston area communities. Buffalo Bayou is unique from this perspective because
the watershed that it drains is almost entirely within Harris County and primarily within Houston’s city limits.
This is not a situation involving a longer river where upstream and downstream communities have different
interests. River science teaches that natural river systems seek and generally achieve what fluvial
geomorphologists call “dynamic equilibrium,” but the process of achieving that equilibrium occurs on geological
time scales far longer than individual human lives. Buffalo Bayou may seem quiet and “natural” to those of us
who hike, canoe and picnic there, but on a geological time scale the changes documented in sixty (60) years of
aerial photography are rapid indeed. On a geological time scale, the Buffalo Bayou channel in the Project area
is snaking about like a high pressure water hose left untended on the ground.
CONCLUSION
BPA supports the Project because it believes that the scientific, design and engineering principles underlying
Natural Channel Design are sufficiently robust, well-defined and understood to justify going forward with the
Project. It is still a young discipline, and the Project is indeed, a Demonstration Project, but not a test or
experiment. There is risk, not associated with the river science itself, but with such events as a catastrophic
rain event just after project completion. BPA shares the values of the environmental community and
recognizes the fear and mistrust that a large project of this type arouses but believes that the balance of risk
and reward justifies the Project. The public-private partnership of HCFCD, the City of Houston and the River
Oaks Country Club presents a unique opportunity to improve public stewardship of Buffalo Bayou, and should
be embraced for this reason.
If there are questions on this set of comments, please contact Mr. Steve Hupp, M.S., BPA Water Quality
Director at 713-529-6443, or by email at: [email protected].
Robert Rayburn
J. Tynan Kelly
Jack Sakolosky
Steve Hupp
President
Past President
Vice President
Water Quality Director
Attachment – 10 slides
Page 8 of 8
Channel Migration
1930
Channel Migration
1944
Channel Migration
1953
Channel Migration
1964
Channel Migration
1981
Channel Migration
1999
Channel Migration
2010
Channel Migration
1930-1964
Channel Migration
1981-2010
Channel Migration
1916 - 2010
14-0620
Cypress Creek Flood Control Coalition
Letter of Support
14-0623
Bob Lee
USACE _MPDP_Comment_RSLO62314R
14-0625
BBP
Letter of Support
14-0630
SN 22_MPDP_Stat
To:
Mr. Dwayne Johnson
Regulatory Branch, CESWG-PE-RB
U.S. Army Corps of Engineers
P.O. Box 1229
Galveston, Texas 77553-1229
June 30, 2014
Re:
Memorial Park Demonstration Project, USACE Permit Number:SWG-2012-01007
The footprint of the Washington Avenue Coalition / Memorial Park Superneighborhood (SN22) is defined by
Buffalo Bayou to the south, White Oak Bayou to the north, and it includes Memorial Park. The health and
preservation of both the park and the bayous are of great concern to SN22’s residents.
Of the SN22 Council membership, comprised of representatives from our constituent neighborhoods, many
have attended MPDP public meetings, reviewed materials presented, and heard presentations and
comments from those both favoring and opposing this demonstration project.
We recognize that there is a critical need to stabilize the bayou banks to prevent continued loss of property,
and support a coordinated effort to lessen the impacts of erosion rather than continuing the individual and
haphazard approach that has been occurring unsuccessfully through the years.
We also recognize that as development continues to densify throughout the watershed without providing
sufficient runoff mitigation, our natural waterways will be increasingly stressed by heavier storm water flow
volumes.
The MPDP takes a context sensitive and environmentally appropriate approach toward resolving these
issues, and attempts to apply the best scientific stream restoration practices to this short bayou segment that
has been experiencing rapid change.
We do request that full evaluation of any revised drainage capacity be initiated to assure that adjacent
neighborhoods in the watershed are not subject to increased risk of flooding.
Additionally, we would encourage adequate follow-up to evaluate the success of the project to assure that
reduction in erosion, re-growth of the riparian and upland native vegetation, reestablishment of wildlife
habitat, and improvement to downstream water quality occur as anticipated.
Bayou Preservation Association, in conjunction with Harris County Flood Control District, is knowledgable
about the functional needs of this waterway, has been thorough in making the public aware of the project
details, and should be trusted to act in the best interest of the bayou’s protection.
It is imperative that a solution be found that will allow a natural Buffalo Bayou to co-exist within, and
effectively serve, this increasingly urbanized watershed.
The SN22 Council supports the Memorial Park Demonstration Project as a viable first step
toward achieving that goal.
Thank you for your consideration of our comments,
Tom Dornbusch
Superneighborhood 22 Council President