Since 1849, when Major Ripley Arnold chose the confluence of the Clear Fork and West Fork to build a fort, the Trinity River’s jagged, sprawling, lightning bolt-looking channel has connected the city and its residents to the region, the state and ultimately to the Gulf Coast 400 miles away.
Locally, it’s been a rocky relationship. Snaking through the city’s west, north and east sides, the river’s roiling floods in the early 20th Century led to deeper channels and higher levees, for years remaking the Trinity River into a trash-clogged open pit that people ignored.
Then, 50 years ago, the Trinity River experienced a rebirth. Starting with new low-level dams to regulate water flow, efforts to welcome the river back into resident’s daily lives included building more than 40 miles of trails, planting more than 8,000 trees and developing acres of new parks.
People kayak and tube in a river they used to shun.
But now the Trinity River is under attack, and this time by the next, gentle rain.
Solid waste such as paper, cups and plastic bags is getting swept up in a storm’s runoff along with the slick, oily grit left on parking lots and roadways. Fertilizers and bacteria not being absorbed into the ground is also in the runoff, enough to limit human contact with the river.
And it only takes a little bit of rain to make a real big mess. All of that can be contained in runoff coming from less than an inch of rainfall.
“Everyone thinks it’s the five-inch storm that’s the worst because they see all that junk (in the water,)” says Fouad Jaber, assistant professor and extension specialist for Texas A&M AgriLife in Dallas. “But it’s the first flush that picks up everything on the ground and brings it in. After the first one-and-a-half inches the water is cleaner because the first flush is done.”
“It’s the one-and-a-half inch storm that comes so frequently. Add them up and that is the worst storm because that represents 90 percent of the runoff that comes in a year,” he says.
To protect the gains in water quality that have been made, the Tarrant Regional Water District in August adopted a Water Quality Guidance Manual to improve the quality of the stormwater that makes its way into the river from streets, parking lots and sidewalks after it rains.
The 175-page manual, described as a “cook book” for landowners and developers, not only establishes guidelines for improving stormwater quality but goes one step further by offering recommendations and resources of exactly how to go about reaching that goal.
While TRWD’s guidelines only apply to the 443 acres that make up the Trinity River channel and its associated floodway in Fort Worth, hopefully they will be accepted by the City of Fort Worth for the 30,000-acre water zone that surrounds the river.
“By adopting these updated water quality policies we continue our decades long commitment to protecting the Trinity River, it’s ecosystem and the people who depend on it for water, recreation and a better quality of life in our community,” TRWD President Jack Stevens says.
The manual recommends using green infrastructures, such as rain gardens, bioswales and green filter strips along with something as basic as permeable pavers and curb cuts to keep runoff from simply going down a storm drain.
It also provides developers and landowners of examples of concrete structures, such as underground sand filters, bioretention basins, floatable and hydrodynamic separators to treat and deal with such things as oil, trash and debris in stormwater runoff.
While landowners may be initially reluctant to take these additional steps, in the long run taking steps to improve stormwater quality can enhance the value of property and ultimately what they pay to the city to subsidize more costly pipes to handle stormwater.
“We’re not just telling them to do something and not giving them a resource of how to do it,” says Robert Brashears, a water resources engineer who at CDM, the engineering firm that helped develop the manual. “Developers and engineers have all the flexibility in the world. They can see what the manual recommends and they can have a dialogue.”
Studies show that cities with these kind of stormwater quality practices not only have improved water quality, but that it has enhanced the aesthetic character of the land near the river, raising property values and making the community even more desirable for development.
According to EPS, a Denver consulting firm, a 38,000-acre corridor surrounding the Trinity River contains 142 million square feet of development space with an assessed value of $10.7 billion. EPS did the study as part of a Trinity River Strategic Master Plan commissioned by Streams and Valleys.
Quentin McGown, a local historian who teaches a class on the Trinity River, says it only logical to take these steps. He describes the river’s transformation from a drainage ditch to a thriving asset as amazing.
“It’s the artery. It’s the reason the community exists. It is the one thing that ties the entirety of the city and the region together,” McGown says. “We’re getting close to being 50 years in this process of refocusing on the river after 50 years of doing everything we could to destroy it.”
“If we continue to screw it up, we kill what at this point appears to have every indication of being one of the greatest economic engines within the central city,” he says.
All shapes and sizes
Studies warn that without taking these steps, the Trinity River could degrade, with higher bacteria levels impacting recreational use. The river’s aesthetics will also decline not only because of increased trash, but by unsightly algae growth caused by nutrients in the water.
As land use around the Trinity River changes, and more concrete and asphalt replaces soil that acts as a natural filter by absorbing rain, landowners need to be encouraged to adopt best management practices known as green stormwater infrastructures, Jaber and others say.
“We’re really trying to remove it (pollutants) from the water as it flows across the watershed before it hits the river,” says Darrel Andrews, assistant environmental director for the Tarrant Regional Water District. “Sediment is not a bad thing if it is in the right place. Phosphorus and nitrogen in fertilizer, it’s okay, but they hit the river, it’s a bad thing. It’s a good thing in the wrong place.”
“Bacteria, although natural – I don’t know if it’s good to have that ever – but the ground is a more natural place for it to break down. Once it hits the river, it causes problems.”
“And floatables – like cups, bottles, plastic bags – that is not good anyplace,” Andrew says.
Green stormwater infrastructures come in all shapes and sizes.
Some of the infrastructures take in broad swaths of land while others use strips of land along a property’s edge or in narrow rain gardens between parking lot slots. Design elements include trees, grasses and gravel as well as subterranean pipes, concrete boxes and sand filters.
Exactly what method will depend on the property’s size and how much water flows across it. But the key principles are to take the stormwater and slow it down, spread it out, and soak it in.
“This whole thing is about waving a flag that there is as better way doing this and you’re property will look better and provide amenities that people will enjoy using,” Andrews says.
Brashear’s firm worked on the water quality manual for three years.
“The district took a painstaking effort to put together a manual that has a process that is as easy as possible to implement and fits in well with the city of Fort Worth development process,” he says.
Other communities and institutions already use green stormwater infrastructures.
The University of Texas at Arlington the Green at College Park offers neighbors and downtown visitors a retreat from urban life with a large lawn and seating along a curved stone wall that overlooks native grasses and adaptive plants. The three-acre park acts as a “green sponge” by directing stormwater through a micro-depression that filters rainfall through vegetation and soil. It also slows down the water, allowing sediments to settle, so pollutants can be broken down.
Rayzor Ranch in Denton, a 400-acre mixed-use development, in its overall landscape plan used multiple green infrastructures including a water quality pond, a pocket wetland and an enhanced swale, or a low tract of land used to filter stormwater. But not every element of Rayzor Ranch’s stormwater plan required large chunks of land. Included were parking lot islands and filter strips – sloping, grassy areas – that treat stormwater runoff before it leaves the property.
Research shows that measures like these can significantly reduce pollutants in rainfall runoff. A 2015 study by Jaber revealed that test rain gardens in Dallas reduced nitrates and orthophosphate by 70 and 90 percent, respectively, in the rainwater runoff. Having too much of either compound can kill vegetation and fish.
There was a 65 percent drop in bacteria, the study shows. Certain kinds and concentrations of bacteria, such as E-coli, can lead to sickness and disease in humans.
The guidance manual prepared for TRWD by CDM Smith states that requiring this kind of best management practices are needed along the Trinity River. Their studies show that without changing how stormwater is handled near the river, “the current quality of the Trinity River in Fort Worth could degrade significantly to the point contact recreation activities, such as swimming, will be impacted due to elevated amounts of bacteria.”
“Without intervention, the aesthetics of the river will decline as well due to increasing amounts of trash in the river and unsightly algae growth from increases in nutrients which also impact aquatic life,” the study states.
It is necessary for green infrastructure to be integrated into a development if the Trinity River – and other waterways – are to be protected, says Jaber. He reviewed the CDM report and praises TRWD for implementing these new stormwater quality guidelines.
“This is what we need more of in the cities in North Texas. We need good guidelines for developers and engineers and some minimum mandatory requirements so we can reduce pollution,” Jaber says.
Take it to the bank(s)
Better stormwater quality is not only good for the Trinity River, it’s good for business.
Already thriving along the Clear Fork is the Waterside, a 63-acre, $185 million development on the former Lockheed Martin Recreational Association site. About 25 percent complete, it could be home for two hotels, 1,200 residential units and 270,000 square feet of retail space.
Less than two miles away and straddling the Trinity River is the $300 million, 270-acre Clearfork development. Built on the historic Edwards Ranch, Clearfork is home to million dollar houses and The Shops at Clearfork, a luxury shopping area. It’s Press Cafe is a hotspot along the river.
Plans for commercial and residential activity doesn’t stop there.
Besides the $1 billion Panther Island project that includes 10,000 residential units and more than three million square feet of commercial and retail space, there’s talk of building Trinity River’s east and west sides close to downtown.
As a result, reducing the pollution threats to the Trinity River becomes critical. But implementing the appropriate stormwater quality infrastructure, while adding to a development’s costs, can actually make the land and project even more valuable. A draft Trinity River Master Plan conceived by Streams and Valleys, the city of Fort Worth and TRWD states that the population within one and a half miles of the Trinity River has grown by 20 percent since 2000.
In what is known as the “Proximate Principle,” developed by Texas A&M University’s John Crompton, says property near a park or open space frequently has a higher value than other, comparable properties. In an article published in 2018, Compton and Sarah Nicholls at MIchigan State University specifically found that property near a lake or river that clean water has a positive effect on property values.
“Where this has been done in other locations in the country, it has often not only had the desired effect of protecting water quality, but it has also improved the aesthetic quality of the land surface, raised property values, and made communities more desirable,” the CDM study states.
Well-designed landscaping and bioswales for office buildings boost rental rates by 7 percent and retail customers were willing to pay 8 to 12 percent more in shopping areas with mature tree canopy, according to a 2013 study by the National Resources Defense Council.
If it’s a mid-size retail center, this could mean over $1 million of increased sales a year, the study found. Additionally, the higher revenue meant that building owners should be able to charge higher rents for providing green infrastructure amenities, the NRDC reports.
So it comes as no surprise that many developers say that dealing with stronger stormwater regulations ended up being a positive experience and would not deter them from using green infrastructure in future projects, according to a study by the Urban Land Institute.
“It is an amenity. It can make new development better,” Jaber says, adding that they can usually sell their property “for a higher price.”
After nearly 50 years of working to make the Trinity River a vital part of the community’s social fabric again, everything possible must be done to protect it as the city grows and urbanization paves over more and more permeable open spaces, advocates say.
The city is gambling with the health of the river, something it simply can’t do.
“It’s critical. Everything ends up in the river. Good. Bad. Or Ugly. And it’s going to take all of us working on that together to make some sort of difference …” said Stacey Pierce, executive director of Streams and Valleys, a non-profit committed to saving and celebrating the river.
“You can make headway if it is coordinated,” Pierce says.
McGown praises any effort to refocus the city’s life around the river, “which is why we are here in the first place.” But he agrees it is crucial that steps be taken to protect the Trinity River.
“As our population nears a million (in the city of Fort Worth,) we’ve got to figure out a way not to screw up what we’ve got …” he says.
