If you forgot Dallas’ torrential weekend rains, Monday’s return certainly brought those memories … flooding back.
What’s up with that? It’s not like rain is something new to Dallas. Sure, depending on whether your beliefs are fact- or fiction-based, climate change may be making rains heavier, but we’ve always had deluge-type rain (when we’re not in drought).
So why does this city flood like it’s never seen a drop of water? Why do we have to repeat, “turn around, don’t drown” and mean it when the water is coming up to the running board of the SUV? There are many reasons, some just mother nature, some brought on by neglect and — shocker — our city’s indifference to infrastructure.
First, Dallas soil isn’t very absorbent. Sitting in on any number of developer meetings, the call for underground parking is typically met with whining about the cost. Dallas has a layer of topsoil and clay that quickly turns into limestone. This makes underground parking costly and is probably the chief reason there aren’t a lot of basements in Dallas.
Limestone is good from the standpoint that it’s porous and cleans water as it percolates through to underlying aquifers. But it’s still stone and so percolation, at literally dripping speeds, doesn’t cope well with deluges of rain. This produces run-off as the ground becomes oversaturated.
Back before people got here, too much water ran off into temporary pools and into streams and rivers before it was channeled away by larger waterways, evaporated or drank by local wildlife. People made water worse.
First, we’ve covered massive amounts of ground with buildings, streets, and sidewalks. This limits the ability for what little topsoil we have to absorb water. People have also covered any number of formerly free-flowing waterways. This includes “dry” creeks and rivers that are essentially surplus capacity to channel water in times of great need. So we’ve gummed up the natural systems that mitigate flooding.
As we humans built, we were supposed to construct drainage and sewage lines that were equal to the task of evacuating excess water from the lands and waterways we’d messed up. Surprise! We didn’t. In the olden days, the understanding and concepts for mitigating flooding were pretty weak.
And as we humans built these ultimately inadequate drainage lines, it was incumbent on us to ensure they were working at peak capacity. Surprise, surprise! We didn’t do that either. (Who hasn’t seen a tree growing out of a sewer?)
Couple diminished capacity with heavier rains and the result is Dallas’ vehicular water ballet on Friday.
How Do We Fix This?
Thought, money, and regulation. Money for the built-up areas of Dallas and regulation for those new housing developments being torn from open ranch land in the boonies. Thought? We all need that.
You see, the boonies need to regulate their building codes to ensure drainage isn’t merely adequate, but more than adequate for the job ahead. Think of it like buying ice cream. It’s easier to buy a gallon once than to make eight trips to Kroger for a pint. While the ground is open, before all the housing and infrastructure are plopped on top, over-engineer what you need. It’s cheaper in the long run.
For those of us in already incorporated areas of the city, it’s a money game. First and foremost, existing drainage needs to be cleared, sewer by sewer. When police and other city services are out and about, they need to report blocked sewers … sewers with trees growing out of them. Unfortunately, you can’t expect citizens to report these things. Heck, the ice machine scoop has been missing for two months in my building and I found out Friday that no one had even reported it to be replaced. Maybe if people could Tweet a picture and address, but even then …
But I suspect even whistle-clean drainage isn’t completely up to the task. Capacity needs to be increased. This is where thought and money join forces.
We all know our infrastructure has become too large to effectively and economically maintain. In case we were illiterate, every pothole is a Braille reminder that public monies are at once inadequate and of low priority. The fact that the state has not built a highway in decades that isn’t toll-based is another touchpoint.
That Has to Change
I get it. Infrastructure largely isn’t sexy. For every Calatrava bridge, there’s 1,000 miles of sewers. And while individual and corporate donors like to slap their names on things, no one’s jumping to have a road repair named after them.
Looking at other cities, there are two recurring themes. Restoring and increasing the amount of water that can be naturally sequestered, and large public works projects for the remainder.
One of the largest and longest public works projects was undertaken in Chicago in 1975 and only finished phase one in 2006. Called Deep Tunnel, it’s a 109 mile series of underground tunnels to channel and store 2.3 billion gallons of runoff water during storms. Deep Tunnel cost $3 billion. Phase two will add another 7.9 billion gallons of reservoir capacity using abandoned quarries when it’s completed in 2029.
Combined, that’s more than 10 billion gallons of extra sequestering capacity for rainwater runoff. And it’s still not enough for a city the size of Chicago.
Legislate and Learn
Dallas is clearly too poor for this kind of large-scale project. So what can we do?
Remember in the beginning, I said people are the biggest cause for flooding because of the way we’ve disrupted and covered the natural systems that evolved to handle water runoff?
We need those systems to be restored, too. Look to Seattle, Milwaukee, Philadelphia, and again Chicago to see those efforts literally taking root. Milwaukee is the first city in the nation to require green infrastructure as part of their federal storm water runoff permit. By “green” they mean paving streets and parking lots with water-permeable paving materials and installing neighborhood “rain gardens” that are designed to fill and hold rain water.
Yo, Dallas City Council … send a delegation to Milwaukee’s Global Water Center to learn. When it opened in 2013, the Milwaukee Water Council’s goal was to become the “Silicon Valley” of water. Even before it opened, the area already counted 194 water-related businesses working on solutions to a variety of issues including managing storm water runoff.
Chicago began a Green Alley program back in 2013 that replaces alley roadways with water-permeable pavements to absorb more rain water. The city estimates it has some 1,900 miles of alleys covering 3,500 acres of once-absorbent land. Before you think of cost, water permeable concrete is actually cheaper than conventional concrete and easier to maintain. Win-win.
Even before Green Alley, there was the green roofs initiative started in 2004 by Mayor Daley. Chicago has been a US leader in green roof implementation (but we’re decades behind Europe). Chicago’s City Hall led the way with its own green roof, the first of over 1 million square feet of green roofs installed PER YEAR since 2004 … that’s more than 23 acres of reclaimed green space PER YEAR. Green roofs store 50 to 60 percent of their rainwater, diminish urban heat islands, and cut the energy bills of the buildings they cover. Oh, and they’re pretty.
The most basic green roof is four inches thick and covered with drought-resistant plants like sedum that have the added benefit of flowering into a burst of spring color. Typical roofs last about 20 years. Green roofs last 40-50 years. Yes, green roofs are more expensive, but they’re not double. They just require long-term thinking.
But this is Dallas. I’ve written about the coming development resulting from March’s Preston Place fire. When I told dinner guests last night that I want any new development to adopt green roofing, general scoffing was the response.
This is one of those things you have to be blind not to see the benefits of. The costs can be less (driving force) and you get all the benefits of attractiveness, energy efficiency, diminishment of water runoff and not having to drive down the highway in a pontoon several times a year.
So Dallas, what’s it to be? After all, there were city bonds issued in 2006 and 2012 that had components for Flood Protection and Storm Drainage, where’d that money go? What’s in store for the next bond? In the next installment, we’ll see.
Remember: High-rises, HOAs and renovation are my beat. But I also appreciate modern and historical architecture balanced against the YIMBY movement. If you’re interested in hosting a Candysdirt.com Staff Meeting event, I’m your guy. In 2016, my writing was recognized with Bronze and Silver awards from the National Association of Real Estate Editors. Have a story to tell or a marriage proposal to make? Shoot me an email firstname.lastname@example.org.