CitiesLike many folks, I was heartbroken to see the images of flooding and devastation after Hurricane Harvey drenched the Texas Gulf Coast. I have visited Houston frequently since the 1980s, and I have personally been involved in The Conservation Fund’s work there since 2004 when we helped kickstart some of the initial ecological mapping and planning for start-up of the Houston Wilderness organization. Our colleague Andy Jones was a founding Board member. Around that time, we also worked with the Houston Parks Board to identify urban park acquisition opportunities that would benefit underserved and disadvantaged communities, those that are especially hard hit in extreme flooding events like this.
Since the Hurricane, I have been asked multiple times about The Conservation Fund’s more recent work completed in 2013 in the Houston-Galveston Metroplex, where we designed an interconnected network of natural lands with multiple benefits for people and nature. They have been asking me basically the same questions: 1) Didn’t you help the region identify the best natural areas to protect to help direct development away from flood-prone areas and 2) didn’t you estimate the economic value of the region’s forests, wetlands, bayous, and prairies to assist with flood protection and water quality? The short answer to both questions is yes, and but let me briefly discuss a couple of the initial reactions that I have seen in newspapers and online articles that have attempted to assign blame to development and land use regulations for exacerbating the flooding.
Green infrastructure is an interconnected network of natural lands for people and nature.
First and foremost, the Hurricane Harvey rain event was so catastrophic that some damage to our urban infrastructure was simply unavoidable. Would zoning in the City of Houston have prevented it? No. Would better enforcement of existing stormwater regulations have helped? Yes. But even though some damage could have been mitigated with smarter gray and green infrastructure strategies, Houston’s flat topography and clay soils makes it very challenging to effectively infiltrate water into the ground or move water through natural and engineered systems when the flows are so overwhelming.
However, there are opportunities going forward to rebuild and design new urban communities in a more strategic and resilient way. Houston Wilderness – the author of the 2010 publication entitled A Strategy for Realizing the Economic Value of the Ecological Capital of the Greater Houston Region and the recent publication Ecosystem Services Primer – and other local groups will continue to work tirelessly to make Houston more resilient to extreme weather events through protection of critical land and water resource assets.
Looking back at work from 2013 led by our analysis team of Michael Schwartz, Jazmin Varela, and Ted Weber, let’s get an idea of the scale of the region’s ecosystem services and their economic benefit. Ecosystem services are the collective benefits from an array of resources and processes that are supplied by nature. Forests, wetlands, prairies, water bodies, and other natural ecosystems support our existence. Only recently has it become possible to quantify and reliably estimate the contributions that green infrastructure makes to human well-being and to measure the benefits that nature provides us for free.
The 13-county area surrounding Houston provides an estimated $15 billion per year in water quality, air quality, water supply, flood protection, and climate regulation. These are conservative numbers. 91% of these services value fall within the interconnected network of forests, wetlands, bayous, and prairies we identified—but the network only accounts for 62% of the region’s land area. The bottom line here is that there are still opportunities for future development to accommodate the projected 10 million people who are forecast to live in the region by 2040. But without a focused effort to strategically locate development and conservation, the Houston-Galveston Area Council’s 2009 Eco-Logical report included a forecast that over 985,000 acres of existing undeveloped natural areas would be converted to developed land uses by 2035.
Talking specifically about ecosystem services related to water quality and flood protection, we found that forests in the Houston-Galveston region provide an estimated $200 per acre per year of groundwater recharge. Wetlands are especially effective at absorbing stormwater, reducing flood damages by almost $8,000 per acre year. Forests provide an estimated $105 per acre per year of flood protection that would otherwise have to be performed by engineered stormwater facilities. When you are talking about a 13-county area in Texas, that’s big money. The bottom line here is that one way to better design future development (e.g. minimize impervious surface), water management (e.g. on site detention and infiltration), and land conservation strategies (e.g. protect spongy soils) is to explicitly take into account the economic value of natural systems. 
Our green infrastructure and ecosystem services work was incorporated into the early phases of the Houston-Galveston Area Council’s Our Great Region 2040 initiative. This planning effort confirmed the region’s interest in preserving “unique ecosystems, working landscapes, parks, and open spaces, and the ecological benefits they provide.” The specific recommendations in our report included establishing key green space anchors such as the Sam Houston Greenbelt vision, the Lone Star National Recreation Area, and protection of key upstream areas in the Katy Prairie. Among our longer-term recommendations were the establishment of an easement purchase program for private landowners to maintain and enhance lands for water quality and flood protection and the design of proactive flood mitigation systems through the establishment of entities like the Harris County Flood Control District throughout the region. 
Since we completed our assessment, Houston Wilderness has integrated these priorities along with many others into an initiative called the Gulf-Houston Regional Conservation Plan. The bottom line here is that these investments do cost money, but they would be a drop in the bucket relative to future recovery costs from flood events that will inevitably continue. Let’s explore these Texas-sized ideas that would ‘move the needle’ on making Houston’s development patterns more sustainable and resilient.
Here’s hoping that there will be a change in mindset that investment in protecting natural systems is not a hindrance to development but is instead, simply good business.
Download the Houston-Galveston Green Infrastructure and Ecosystem Services Assessment here.
