In Florida, rising sea levels threaten cities along 1,350 miles of coastline, while dwindling inland aquifers fill with salt water. Can smart water usage and civil engineering save Florida?
The low-lying Sunshine State, with its primarily coastal population, is at enormous risk from even a small rise in sea levels. A rise of just two feet would threaten Miami and flood most of the southern tip of the peninsula, affecting over 500,000 people and 350,000 homes. A five foot rise will wipe out over 2 million acres of land, and hit 1 in 6 of the population.
This is not a hypothetical worst case scenario, or a climate model fed with deliberately bleak assumptions. “Miami, as we know it today, is doomed,” says Harold Wanless, chair of University of Miami’s geological sciences department. “It’s not a question of if. It’s a question of when.”
The writing is quite legibly on the wall. Whenever there is a combination of full moon and a high tide, sea water comes up through the old storm drains and pours into the streets of Miami Beach. Massachusetts engineers CDM are currently working on a $200m system to build new sea walls, add more stormwater drainage pumps, refurbish existing storm discharge pipes and install one-way valves on outlet pipes so that the sea water cannot flow back into the city.
That’s a great start but it’s only designed to handle six inches of sea-level rise. Most experts agree that that’s a low-ball estimate for what the next twenty years will bring. City Commissioner Michael Góngora is sanguine about what will happen when the seas rise higher still, “I trust we will find a solution. I have been to Amsterdam. I have seen what the Dutch have done. If they can figure it out, so can we.”
Miami Beach city engineer Richard Saltrick has a much more radical solution: raising the entire city.
Sea walls don’t work, he points out. The water just seeps through the limestone that underlies the city. And since they’d have to be built on private property, how would you compel individual homeowners to build walls to a suitable standard? Just one breach in the the 60 miles of wall would render the entire thing useless. The city is already planning to raise the roads, but as Saltrick points out, “When you raise the road even a few inches, what happens to the water? It runs off the road into the buildings and homes alongside it. So you have to raise those, as well. It’s a huge undertaking, but someday, it may come to that.”
The Flood from Below
Eric Rollings is Chairman of the Orange County Soil & Water Conservation Board, based in Orlando, Florida. He’s acutely aware of the extent to which water problems are affecting even the inland regions of the state. Here, the issue isn’t rising seas – it’s water shortages.
“We have a rapidly growing population here in Florida,” he says. “People are moving from California, and coming to a state with similar weather and lower property prices. And as farms fail in California, we’re increasing our agricultural output here. That’s great for business, for farmers, and for property developers, but it comes at a huge price. We’re drawing more and more water from our aquifers, and that’s not sustainable. California is the canary in the coal mine. We have to act now if we don’t want to end up like them.”
Worse than that, Florida’s porous bedrock means that existing water supplies are being threatened. “As we draw more from the aquifers, the sea slowly seeps in,” explains Rollings. “We’re actually contaminating our own well water because we’re being too greedy and inefficient. In other places, we’re drawing so much water out that we’re increasing the risk of sinkholes. It has to stop, now.”
For Rollings, the answer lies with a combination of technology and enforcement. “Here in Florida, we have a lot of rain,” he says with a grin. “So we should mandate that every home and office building should have a rain catchment system. A typical 2-bed house of 1200 square feet would collect 40,000 gallons of water a year: all of that runs down our streets and into culverts, instead of being used. That’s what people should use for watering their lawns and flushing their toilets. They shouldn’t be using water that’s been pulled out of the ground, then treated to drinking standards, for that.”
He points the finger squarely at lawns. “How often have you driven past a lawn with the sprinklers going during a rainstorm?” he asks, with more than a trace of irritation. “That’s just stupid. We should require people to use moisture sensors, and only irrigate when the grass actually needs it. And make them plant drought-tolerant lawns.”
Rollings is very practical about how to make such solutions work. “You can’t just order people to do these things,” he shrugs. “They’ll find a way round it. So first, you have to engineer affordable solutions. Most people want to do the right thing, but they can’t. They won’t spend a few thousand dollars. They just don’t have it. So we have to offer them something they can afford. Then we have to reward them, maybe with sales tax cuts on water-saving equipment, or property tax incentives. Homebuilders should be forced to offer a green package, which is more water and power efficient, and in return, we’ll cut them a tax break. Right now, it’s hard to make it economical, since water’s so cheap. In Orlando, residential users pay about a dollar per thousand gallons. But wait till water gets scarce, and gets expensive. People are happy to pay over a dollar a gallon for bottled water. What if you had to pay that for the stuff that comes out of your tap?”
How Can Engineers Save Florida?
It’s all too easy to think that the solutions lie in the hands of a few big headline projects, but nothing could be further from the truth. Every home owner, every business will need to do their part to reduce water consumption. Compulsion or taxation will be politically hard to implement. The answer will involve changing the minds of water consumers, and that’s where engineers of almost every discipline will need to be involved.
First and foremost, water-saving products need to become more affordable so that people can see an immediate saving. Creative Engineering’s Tap-n-Flush and Scheid’s smart agricultural systems are just two examples. Once water users can see a financial benefit, they’re more likely to invest in adopting those technologies. Manufacturing engineers will need to develop products that can be mass produced cheaply, using new materials and innovative designs.
Second, our homes, industrial buildings and offices need to be designed and built with water-saving in mind. Steven Smith is a mechanical engineer and Green Plumbing Designer at WSP in Houston who has worked on construction projects all over the world. He sees major changes in the near future. “You need to get engineers and architects to think about water usage the same way they do about power usage. A few years ago, this wasn’t something most people were aware of, and you had to design everything yourself from scratch, which was expensive. It’s hard to get owners to buy into that extra cost, especially since water’s so cheap. That’s all changing now. Many of the things we need are available off the shelf at a reasonable cost. We can just show them how we put all these designs and devices together, and they can see the savings. It’s just a matter of training the engineers to have that foresight and take water into consideration.”
Smith employs a range of techniques to make buildings more water-efficient. “It’s usually a matter of getting with the architects and civil engineers early in the process. If you’re digging the foundations, then get them to think about rainwater collection and dig a hole for water storage at the same time. Once the building’s up, it’s much more expensive to retrofit that. On the other end of the scale, we look at the plants they’re putting in the buildings. Are they using plants that require a lot of watering?”
However, it’s manufacturing that has the potential to make perhaps the most surprising amount of difference. “We work with business owners to see their actual usage and track costs,” says Smith. They’re often unaware of how much they’re wasting, and how much they could potentially save.”
Paul Dowd, CEO at Creative Engineering, talks us through the analysis process. “Water is used in many ways, but perhaps the most important one is power usage. It’s not just about the water used in a plant, though that’s obviously important too. Every time a business is using power, whether it’s electrical or fuel for vehicles, they’re indirectly using water. If you can reduce their energy consumption, you’re saving water. That manifests in surprising ways. If you can cut down the number of trips a forklift is making around a factory, that’s part of it. If you can reduce the amount of packaging so you can fit more items on a pallet or a truck and reduce the transportation overhead, that’s another part of it.”
Hydro engineering may not be the most attractive side of engineering: it often involves dealing with toilets, sewers, and even cat poop. However, as Scheid emphasizes, it’s essential. “The pressure is on. The challenge is to leverage all the technologies that are out there, and wrangle all these different elements into a total solution we can present to people and get them to change the way they think about water without it being a problem.”
Smith agrees wholeheartedly. “We know how to do this. We know we need to do this. Now we need to find ways to make it economical, and make it part of our mindset.”
Rollings is upbeat about the potential opportunities. “Done right, environmentally aware engineering could be a massive economic boom. We can’t continue closing our eyes to what has to be done, so why not make this a positive thing? Engineers and businesses working together can create the solutions that politicians and consumers worldwide all need.”
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