At Water's Edge

By Jim Blackburn

Houston has long had a love-hate relationship with water. We love the prosperity its shipping and recreation brings, but we hate the horror that comes with flooding, and we have not yet learned to live with that dichotomy. But there is hope on the horizon.

Houston stands at a crossroads. The city's economic prosperity, viable social structure, and functioning ecologic systems are all tied to how it addresses water and flooding in the years to come. The question is whether Houston will stay on a path that emphasizes control of nature or change its approach to embrace and learn to live with the water and ecological opportunities that abound in the region.

Deluged with flooding in recent years, Houston is learning to live with water, rather than trying to control it through hard infrastructure solutions alone. Water storage near the Hunting Bayou Greenway is one piece of that puzzle. Photo courtesy Houston Parks Board.

Historic perspective

To get the full picture of the city's path forward, we must first look to its past. Prosperity followed the destruction of Galveston by the 1900 hurricane. Both the modern-day Houston Ship Channel and the Panama Canal were opened in 1914, bringing global commerce to Houston — a boom that was reinforced and expanded by the oil fields and refineries of East Texas.

Alamy photo.

Early development was centered along Buffalo Bayou and its ocean-going commerce, but proximity to the bayou led to massive flooding in the 1930s. As a result, the Harris County Flood Control District was created in 1937.

Development and developers have always been powerful in Houston, as has a strong sense of property rights and a wildcatter entrepreneurial spirit. This attitude was reflected in the rejection of zoning by voters in local elections in 1948, 1962, and 1994. As of the mid-1970s, there were no floodplain maps and no flood-related restrictions on development within the 22 watersheds in Harris County. Federal flood insurance and minimum floodplain regulations came in the early 1980s, an important source of financial support for flood victims but also an incentive for continued occupation of high-risk areas.

But history did not prepare us for the 21st century and its changing climate. In June 2001, Tropical Storm Allison dumped 21 inches of rain in six hours and 28 inches in 24 hours. Then came the Halloween, Tax Day, and Memorial Day floods in 2015 and 2016 and the crushing blow of 48 inches of rain from Hurricane Harvey over four days in 2017, followed by 21 inches in 24 hours from Imelda in 2019.

Perhaps no bayou reflects the dilemma of modern-day Houston as does Brays Bayou, which runs across Southwest Houston through the Texas Medical Center and into the Houston Ship Channel east of downtown. Brays was channelized by the U.S. Army Corps of Engineers in the late 1950s to provide flood protection from a 200-year-plus storm event. However, runoff was not effectively regulated as the watershed became covered with impermeable surfaces, storm sewers, and ditches. Today, Brays Bayou can barely contain a five- to 10-year recurrence storm; almost 27,000 homes were flooded along Brays during Harvey. A soon-to-be-completed $550 million federal structural project, known as Project Brays, aims to reduce future flood damage. It includes 21 miles of channel modifications.

But rainfall is not our only flooding problem. Hurricanes also generate surge flooding that is violent, deadly, and incredibly destructive. Hurricane Ike, which came ashore in 2008, generated a surge larger than predicted for a Category 2 storm due to its very large wind field. It destroyed the Bolivar Peninsula and portions of Galveston but generally missed the Houston region. However, if Ike had come ashore south of Galveston where it was originally projected, it would have likely killed thousands of Houstonians who did not evacuate because it was "only" a Category 2 storm. It also would have spilled millions of gallons of oil and hazardous materials. That surge threat remains very real.

The Brays Bayou Greenway is part of a network of waterfront parkland first envisioned by Arthur Comey in his 1912 plan for Houston. Photo courtesy Houston Parks Board.

Arthur Comey's 1912 plan for Houston. Map courtesy University of Houston Libraries.

Addressing flooding

In a world where flooding is the new reality, many experts say the Houston region's past approach to development must be reconsidered and changed. The first step toward that new future will require living with water rather than trying to control it with stormwater management infrastructure.

"No city in the world could control the 47 inches of rain in four days from Harvey or the 21 inches in six hours from Allison. You cannot afford to design a stormwater system to handle these volumes of water. Instead, you have to work with that water and attempt — at best — to manage it with storage, conveyance, and protected housing rather than control it," says Phil Bedient, PhD, a noted hydrologist and the director of the Severe Storm Prediction, Education & Evacuation from Disasters Center at Rice University.

This approach will require the city to be realistic and accept the fact that many areas will continue to flood, even with significant flood management work, and to embrace nature and set aside open space for flood waters to occupy. Otherwise, water will make its own path.

Second — and even more politically difficult — making room for the water will likely require the removal of homes from harm's way. About 25 percent of Harris County is currently in the now-obsolete 100-year floodplain map that is currently undergoing revision. More than 150,000 homes were flooded in Harvey across all 22 watersheds in Harris County. Portions of all these floodplains will need to be permanently evacuated to make room for living with water, as well as for building water management structures.

The number of homes needing to be bought out could exceed 50,000 — a difficult task in a city with strong neighborhood affinities and a limited supply of replacement housing for residents with lower incomes. In the long term, however, buyouts will likely prove to be the best economic investment as Houston takes action to eliminate repetitive flood losses.

In the process of these two steps, Houston has the potential to become a "greener city" in a literal sense as well as in a more philosophical sense. Interestingly, in making room for the water, Houston may begin to exhibit a pattern of development around the bayous first set out by Arthur Comey in 1912 and revisited, but never implemented, many times since.

Comey famously said, "The backbone of a park system for Houston will naturally be its bayou or creek valleys, which readily lend themselves to parks and cannot so advantageously be used for any other purpose." Today, we are beginning to appreciate the wisdom of this vision from a century ago.

Living With Water: The Bayou Greenways Plan

The Bayou Greenways Plan is creating an integrated system of open space and trails along the major bayous within Houston and Harris County that will also protect the region during flooding by providing water storage and conveyance capacity.

Map by Hassam Hussein, source map courtesy Houston Parks Board.

Right direction

Several key actions are currently emerging that could make a very big difference in the future of the Houston region and its evolving relationship with water.

BAYOU GREENWAYS PROJECT

Harris County passed a $2.5 billion bond issue in 2018, making significant money available for channel widening, retention and detention pond construction, and buy-outs. This money is spread around 22 watersheds and will be added to about $700 million in federal funding. Much of this work will be undertaken within the footprint of the Bayou Greenways 2020 project, an initiative of the Houston Parks Board launched by the passage of a city bond referendum in 2012. This concept of open space and trails along our watercourses is consistent with the concept of making room for the water. This city effort is joined by an ongoing effort of Harris County Precinct 4 to create greenways along Cypress and Spring Creeks in northern Harris County. Together, these projects form a green spine that will transform the landscape of Houston and Harris County. Interestingly, some of the best planning work in the city is being completed by the Parks Board in association with the Bayou Greenways Project, planning that considers neighborhood connections and equity as well as recreation and flooding.

SURGE FLOODING PROTECTION

Two complementary structural concepts have been proposed to protect southeast Houston and Harris County and northern Galveston County from hurricane surge flooding. The one most closely linked to Harris County and Houston is the Galveston Bay Park Plan, a multiuse levee system along the edge of the Houston Ship Channel that combines 25 feet of flood protection, navigation enhancement and dredge material placement, public recreation, and wetland construction. This in-bay levee system is a complement to the Corps's coastal barrier that proposes a major gate structure across the two-mile opening between Galveston Island and the Bolivar Peninsula, as well as an expansion of the sand dune complex on Bolivar and Galveston Island and a back-side levee around Galveston.

Some notable differences surround these two proposed projects. The coastal barrier is being pursued along a traditional path that includes planning work by the Corps and the potential of federal funding and construction. Its cost has been estimated at between $13 and $20 billion. By contrast, the Galveston Bay Park Plan was developed by the SSPEED Center. Rather than federal funding, the park plan will seek to raise its estimated $3 to $6 billion construction cost through creative funding sources such as social impact and resilience bonds. It is proposed to be constructed under permits issued by the Corps to a local governmental entity rather than as a federal project, and it includes the creation of a park with extensive wetland plantings and recreational access to Galveston Bay. (The article's author is codirector of the SSPEED Center.)

It is hard to predict what will actually be constructed. The coastal barrier project has formal Corps sponsorship and the support of Texas's U.S. congressional delegation. The Galveston Bay Park Plan is combined with dredging that is needed to create a safer navigation system. Both projects are currently in the process of refinement and require further environmental review.

GREEN STORM BUFFERS

Because county zoning is not enabled in Texas and regulation is generally disdained, the SSPEED Center designed two nonstructural alternatives around economic incentives to help establish a nature-based hurricane surge and damage buffer. These are the Texas Coastal Exchange and the Lone Star Coastal Recreation Area.

The Texas Coastal Exchange is a nonprofit entity that is making grants to landowners who protect and enhance the ecological services — such as the sequestration of carbon dioxide — on their private property. These grants are funded by individual and corporate donors who contribute to the Texas Coastal Exchange in an amount equal to their carbon footprint at the rate of $20 per ton of carbon sequestered.

This program was initiated in late 2018 and so far is working with coastal wetland owners. To date about 10,000 acres have been enrolled in the program, which is now open for donations for footprint sequestration. The first round of grants will be paid out in early 2020 based on footprint donations from 2019. The long-term goal is to expand this program to cover two million acres with grants to owners of coastal wetlands as well as coastal prairie and bottomland hardwood ecological systems, which will be added in 2020.

Living With Water: Green Storm Buffers

The future of the Texas coast could be much greener thanks to two major proposed efforts combining flood damage reduction with open space projects. In light green (below) are conserved areas proposed for the Lone Star Coastal National Recreation Area. In orange are high-risk surge areas targeted for carbon storage by the Texas Coastal Exchange. Also shown are lands included in the Galveston Bay Park Plan and the Bayou Greenways project, as well as a structural coastal barrier designed by the U.S. Army Corps of Engineers.

Map by Hassam Hussein, source map by Christina Walsh for the author.

The second nonstructural economic approach is the proposed Lone Star Coastal National Recreation Area, which is based upon the best-kept secret of the Upper Texas coast — our excellent wildlife resources and nature-based, historic, and cultural tourism potential. This concept is being developed under the stewardship of the Lone Star Coastal Alliance.

The LSCNRA was designed to network the 250,000-plus acres of nationally significant ecological resources of the federal, state, and nongovernmental organizations with a national park unit called a National Recreation Area. Because it requires federal legislation, which has not yet been introduced and could take years to pass, the concept is being implemented as a regional collaboration. The idea is that the conserved lands of the region will be networked together as part of a nature-based, historic and cultural tourism destination in collaboration with stakeholders in the region. Wayfinding and interpretive signage and subject-based trails and routes will guide the traveler throughout the vast region, and education programs and courses will be established to develop the local workforce and inspire entrepreneurship and investment in the local travel and tourism industry.

In this way, a viable economic sector that benefits local communities, requires little to no additional built infrastructure, and recovers quickly following flooding will be created in the highest-risk flood zone of our region.

Jim Blackburn is a professor in the practice of environmental law in the Civil and Environmental Engineering Department at Rice University, where he teaches sustainable design and environmental law. He is codirector of the SSPEED Center and a faculty scholar at the Baker Institute. His newest book is A Texan Plan for the Texas Coast.