Greater Houston, which is centered around Harris County, is among the fastest-growing metropolitan area in the U.S. The Houston Ship Channel is one of the busiest seaports in the U.S. The Arkema plant northeast of Houston is one of the most hazardous in the state. A series of explosions occurred at the plant due to Harvey-related flooding, resulting in toxic fumes being emitted into the air. Residents within 1.5 miles of the plant were evacuated. Harvey also caused many refineries and chemical plants to release more than 2,700 tons of extra polluted air, affecting the health of many residents nearby. The neighborhoods near refineries and chemical plants tend to be low-income, minority communities with limited resources.
Addicks and Barker Reservoirs were built as flood control devises for the Buffalo Bayou. However, recent developments upstream of the reservoirs had resulted in an unprecedented amount of runoff to enter the reservoirs during Harvey. Water release from the reservoirs into the Buffalo Bayou was mandated to prevent dam breaks and thus more severe flooding downstream. The two reservoirs are among the most dangerous in the nation. Dam breaks could lead to catastrophic floods along the Buffalo Bayou and the Ship Channel to trigger more explosions of chemical plants and refineries.
Most of the other damages by Harvey were related to a heavy and prolonged rain event that led to inland flooding once the capacity of the existing sewage system had been exceeded. The storm surge from Harvey was minor to moderate. Most of the refineries and chemical plants are much more vulnerable to storm surge flooding. The real worst-case scenario can be brought by a much stronger hurricane storm surge up the Ship Channel. The bottleneck effect by the channel mouth could significantly magnify the storm-surge-induced water level increase to shut down the Port of Houston, paralyze the oil industry, and trigger widespread explosions.
The watersheds around Galveston Bay have been rapidly urbanized to lead to flash flooding that can compound storm-surge-driven coastal flooding at the mouth of the Ship Channel and other deltas around the Bay. The Buffalo Watershed is vulnerable to this flooding scenario because it is mostly located within Harris County with the second highest population among all counties in the U.S. When riverine flash flooding coincides with high tides, flood-induced explosions are highly probable during a prolonged rain event even without hurricane-driven storm surges.
The region will soon experience perennial drought broken by a couple of 1000-year storms each year. The 1000-year storm, as a precipitation alone, can easily devastate the oil industry with inland flooding due to overwhelmed sewer systems even in the absence of riverine flooding and coastal flooding. A greater water depth at the Bay, as a result of land subsidence and sea level rise, will incapacitate all industries and neighborhoods nearby with widespread explosions and sewer overflows even on a sunny day. This greater water depth at the Bay will also exacerbate hurricane-driven storm surges to create the worst-case scenario when they are coincided with high tides, inland flooding from 1000-year storms, and riverine flooding from both runoff convergence and dam breaks.
Alternative Futures. We will use Adaptive Water Urbanism as a point of departure to disentangle the compounding effects of coastal, riverine, and inland flooding due to an extreme weather event and sea level rise. To design for future uncertainty, we will self-organize into six teams to design for six alternative futures, which are determined by three common adaptation attitudes towards either the best-case or the worst-case scenario as shown below:
|Evacuation (E)||Adaptation (A)||Relocation (R)|
|Best-Case (B)||Future BE||Future BA||Future BR|
|Worst-Case (W)||Future WE||Future WA||Future WR|
Scenarios. The best-case scenario assumes that the impacts of more intense storms and sea level rise have been minimized by replacing major man-made sources of catastrophic events, such as refineries and reservoirs, with more resilient alternatives. The worse-case scenario hypothesizes that these sources of potential threats remain and ultimately lead to flood-induced disasters, including explosions and flash floods.
Adaptation Attitudes. Emergency evacuation suggests status quo with low-cost solutions either due to the significant time it takes or the lack of substantial funding to implement costly structural adaptation strategies. This scenario also includes synergizing resilient measures with other existing or proposed public realm improvement or infrastructure projects, such as the greenway plan. Adaptation in situ implies reinventing the physical environment to enable living with water in situ and thriving with the threats water brings. Proactive relocation assumes a community-based approach that facilitates strategic retreat from vulnerable towards resilient areas to minimize relocation’s impacts on access to support networks and job opportunities. This scenario will focus on the use of upstream water retention as community amenities and ecosystem-service providers that help generate public support for additional housing units.
Vision-Testing for Each Alternative Future. Each team will create a vision narrative for each alternative future. The narrative will describe a future context as a problem statement and a corresponding adaptative design response. The context and the response should be informed by our collective inventory, analysis, and evaluation of the region’s past, present, and future and the best practices for climate adaptation from around the world. Each team will gradually fine-tune its vision narrative with public input and research.
Phasing for Each Alternative Future. You are to provide a phasing approach to implement your chosen alternative future. A short-term, mid-term, and long-term plan should be proposed based on what can be realistically accomplished and the forecasted conditions for storms and sea level rise by 2030, 2050, and 2100. The short-term proposal should set the stage for the mid-term proposal, which should logically unfold into the long-term proposal.
Process. To study waterfront conditions and identify potential water detention and retention sites, we will divide Greater Houston into the following five medium-scale focus areas organized by the watersheds within the region:
1) Westside: Addicks Reservoir, Barker Reservoir, Buffalo Bayou, Little Cypress Creek, and Upper Cypress Creek.
2) Northside: White Oak Bayou, Hunting Bayou, Greens Bayou, Lower Cypress Creek, Willow Creek, and Spring Creek.
3) Southside: Brays Bayou, Sims Bayou, Vince Bayou, Sims Bayou, Armand Bayou, and Clear Creek
4) Eastside: San Jacinto River Carpenters Bayou, Luce Bayou, Jackson Bayou, Cedar Bayou, and Spring Gully and Goose Creek
5) Beyond: Other watersheds terminating at the Bay, the Bay, and the Coast
Each scenario team will assign one person to each of the five focus areas. If there are six people on your scenario team, the sixth team member will work on the last focus area, which is the largest and can use more help.
The entire studio will collaborate on the inventory and analysis of the region’s water, social, and health systems to identify resilient and vulnerable communities. Subsequently, evacuation teams (BE and WE) will focus on possible resources (routes, shelters, hospitals, etc.) for evacuating vulnerable communities to resilient areas according to the best-case or worse-case scenario. The adaptation teams (BA and WA) will select feasible vulnerable communities for implementing adaptation in-situ for their respective scenario. The relocation teams (BR and WR) will identify suitable resilient communities as relocation destinations given the best-case or worst-case scenario. You are encouraged to find ways to solicit input from the communities by interviewing key informants through online surveys, telephones, emails, or videoconferencing interfaces.
We will distill adaptive water urbanism prototypes from worldwide best practices for adapting communities to inland, riverine, and coastal flooding. Each scenario team will use prototype-specific SWOT (strength-weakness-opportunity-threat) analyses to select possible sites for deploying these prototypes as interconnected systems of kit-de-parts. You will focus on the communities you selected and/or their interconnections to site inland flooding prototypes. You will select potential locations for implementing coastal and riverine flooding prototypes based on the waterfront conditions and potential water detention and retention sites you investigated at the beginning of the studio. As you identify possible intervention sites, strive to untangle the compounding effects of inland, riverine, and coastal flooding while facilitating regional interconnections among these prototypes.
You will have the opportunities to go to one or two optional design game workshops to share your regional, community, and prototype-specific analyses with experts, stakeholders, and high school students. For those opting out of the workshops, you will still contribute to workshop preparation and incorporate design game outcomes by working closely with others volunteering to host the workshops. Each scenario team will use the design game outcomes to generate a consensus-based urban design framework plan, which is a large-scale conceptual diagram for illustrating the locations, connections, and types of prototypes relevant to your scenario. This scenario-specific urban design framework plan will be used to guide each member’s efforts for master planning and site-specific design.
Using a phasing approach, each scenario team will develop a community master plan that implements the strategies of the regional urban design framework, and reflects the scenario-specific water, social and public health conditions. Decentralized small-scale design strategies as site-specific prototypes should be proposed by individual students in a way that interconnects components within the community master plan into adaptable systems within and possibly beyond the community to facilitate regional resilience to coastal, riverine, and inland flooding.