Tag Archives: flooding

What if all the homeowners in a town or sizable neighborhood wanted to sell at once?

Posted on by

The second part of this headline is thought provoking: “In a Florida Town Ravaged by Storms, Homeowners All Want to Sell.” More from the story:

Photo by Kindel Media on Pexels.com

Hoping it was a fluke, Driscoll tore out the affected drywall and started fresh. After all, the four-bedroom home built in 1960 had no flood history. 

But then it happened again, and again. Like many others in the community, he put his home up for sale in the spring of this year. After seeing little interest, he cut the asking price…

Ballooning home insurance costs and the perennial threat of violent storms are starting to undermine housing markets throughout much of the state. But in few places has the turnaround been more dramatic than in low-lying communities up and down the coast of Florida that frequently flood. 

The Tampa Bay housing market had been softening even before Helene struck. While prices have been flat, the area experienced a 58% increase in supply in August compared with a year ago, and a 10% decrease in demand, according to Parcl Labs, a real-estate data and analytics firm. 

About half the homes listed for sale in Tampa experienced price reductions as of Sept. 9, the third highest share of all U.S. major metropolitan areas.   

It sounds like there has been an increase in people wanting to sell in this area. It is not quite “all” have their homes on the market. Perhaps “all” might want to sell?

Either way, the idea of a large number of homeowners moving away at once is likely rare in recent years. There are ghost towns across the American landscape, whether in mining communities or suburbs. In these cases, everyone left and decades later there are some remnants or possibly nothing left if other land development has taken place.

If residents all left these Tampa neighborhoods, what would happen to the land? It could remain unpopulated if it was determined that these are areas that frequently experience flooding. The land could become wetlands or a buffer zone for nearby land. Or it could be turned over to other developed uses that might be less affected by flooding, whether that might be a park or industrial space.

Recommendation that Chicago residents should use less water during heavy rain

Posted on by

The Chicago region has water and flooding issues. One sign of this is an email I received two days ago during a rainy week and ahead of more rain:

I do not know how many people are on this mailing list or how many people would change their water use patterns based on an email. However, I can see the point: if capacity is reduced and the Metropolitan Water Reclamation District of Greater Chicago knows about it, why not ask?

At the same time, some might wonder why there is a need for this. Doesn’t the region have a modern marvel intended to provide relief from flooding? Haven’t these issues been addressed over the decades?

As the region continues to grow and experience more development, these water issues will likely grow. Pursuing different solutions could help as could changing usage patterns.

Every major rain provides reminders that Chicago and parts of the region were built on swamps

Posted on by

When a large amount of rain is dumped on the Chicago region in a short amount of time, the infrastructure cannot keep up. The swamps underneath the third largest metropolitan region in the United States continue to influence everyday life:

Photo by Eva Bronzini on Pexels.com

The region’s struggle with chronic flooding begins with its location. Chicago and many of its suburbs were built on swamps, and storm runoff has become more difficult to manage as the region has been paved over.

These swamps had at least one advantage. The area between the Chicago River and the Des Plaines was swampy and this portage helped lead to Chicago’s growth as the Great Lakes and Mississippi could be connected.

But, think of all the effort required initially to drain the swamps or fill them in or build on and near them. Some early settlers built plank roads to try to stay above the mud. Then, there are consequences still today with major rains leading to flooded basements and sewage released into waterways. Planning for dealing with water requires resources and time, ranging from retention ponds to dealing with the effects of new nearby development to cleaning up after floods to building the massive Deep Tunnel project.

The article notes the decades-long efforts to address this. Communities within metropolitan regions might not like to pool resources but this seems like an issue that should bring together everyone to make serious headway on solutions in the next few decades.

How much all the buildings in New York City weigh

Posted on by

New York City has a lot of buildings in its 300+ square miles. All those structures weigh a lot:

Photo by Michau0142 Ludwiczak on Pexels.com

New geological research warns that the weight of New York City’s skyscrapers is actually causing the Big Apple — whose more than 1 million buildings weigh nearly 1.7 trillion pounds — to sink lower into its surrounding bodies of water.

Given the innovations that helped give rise to all of these buildings, can we expect innovative solutions to the consequences of all that weight? One approach would be to create barriers between the surrounding waters and the habitable areas. However, that does not fully address the weight and the ground under the buildings. Are there ways to prop up large structures?

Adjustments in suburbs to changing water and flooding conditions

Posted on by

As some sprawling areas of the country deal with drought and limited water, others will be adjusting to changing rainfall and flooding patterns and considering a new Illinois State Water Plan.

Photo by eberhard grossgasteiger on Pexels.com

Cattoor said the plan will not impose regulations on local municipalities but will instead provide programs and data that communities could benefit from…

The recommendation for this issue is to provide localized information to the public on anticipated changes in storm intensity and frequency. According to the document, this is particularly important in communities with combined storm sewer drainage systems, which carry sewage and stormwater runoff in the same piping system.

In Des Plaines, planning is critical to mitigate and reduce floods from large rainstorms that result in the Des Plaines River overflowing its banks.

Floods in 2008 and 2013 caused widespread damage to the city’s Big Bend Drive neighborhood, prompting the demolition of nearly 90 structures to permanently remove them from the floodplain. Most recently, a heavy rainstorm in 2020 left many of the city’s streets underwater…

Duddles said the Metropolitan Water Reclamation District requires that municipalities use an Illinois State Water Survey document referred to as “Bulletin 75” as a source of precipitation frequency data for stormwater infrastructure projects such as detention ponds.

It sounds like this can be helpful for future planning. For those pursuing new development, updated guidance on water and flooding could help limit future issues.

At the same time, work will be needed to adjust existing infrastructure. This is a harder task. In the example cited above, floods led to removing homes. In many suburbs, old systems may not work well as conditions change. Or, new conditions mean that systems that were already taxed or not working well may need severe overhauls.

Where will the resources come from to undertake such projects? Significant pipe, sewer, and water projects are not cheap. Aging infrastructure is a problem in numerous suburbs where the spurt of rapid development decades before leads to routine and unexpected maintenance and replacement.

This all means it could be decades before significant changes occur in suburbs regarding water and flooding. Yet, starting now in communities is better than waiting to address issues.

Adjusting city infrastructure to meet new challenges

Posted on by

What is underneath the streets of older major cities may not be enough to face new weather patterns and additional challenges cities face today. Here are some of the efforts from recent years in New York City:

Photo by eberhard grossgasteiger on Pexels.com

New York had its first climate-related wake-up call nine years ago, when Hurricane Sandy brought a storm surge that flooded low-lying areas and, yes, subway stations. Since then, the city has spent almost $20 million on climate-proofing the city, according to the Mayor’s Office of Resiliency. But some of that funding went to solving a different problem than the one presented by Ida: water coming from the rivers. This week, all the wet stuff fell from the sky, threatening even areas above sea level…

Now, after years of updates, 60 percent of New York City has a combined sewer system, which uses a single pipe to carry both wastewater and stormwater to treatment plants. During heavy rainstorms, the system can get quickly overwhelmed. The detritus of city living—trash, plants, general gunk—clogs drains, further gumming up the works. “So if you get a really big kahuna like this, I don’t think it really has a shot at draining that out fast enough to avoid flooding,” says Farnham.

The city has worked to separate those combined sewer systems and to clear clogged drains, especially when storms threaten. It has raised and in some cases eliminated subway grates, which were built to allow fresh air to flow down to dank underground spaces but which now look like holes to let more water in. In some places, the MTA constructed flood-proof doors, which can close when the water gets too close.

More generally, cities like New York can create more green infrastructure to help with their water problems—basically, less pavement and more dirt. You might, for instance, create roadside green spaces where water can percolate before moving into stormwater drains, removing trash and pollution in the process. Los Angeles has been doing this to catch rainwater. “This is a long-term thing,” says Horodniceanu. Retrofitting cities to deal with what’s coming, and what’s already come, will take gobs of one of the scarcest resources of all: much more funding.

As cities expand and change, fixing the infrastructure already there to incorporate new technologies and grow the capacity is a difficult task. How disruptive will the efforts be? How much will it cost? It could be much easier in the long run to anticipate these issues way ahead of time and proactively make changes rather than only act after a major issue is exposed.

Water is particularly destructive as much of modern life depends on the fact that water will be excluded from the system. Residences, businesses, mass transit, electronics must be dry to function well. If there is an overwhelming storm or a breach of the water defenses, water can quickly wreak havoc both in the short-term and long-term. Cities require a lot of things to go right to properly go about their business but water can quickly disrupt this operation.

The recent events in New York City and New Orleans also remind me of the planning that can go into highways and parking lots: they can be constructed with peak use in mind. The parking lot needs to be large enough to handle the biggest crowds, hence the shopping mall parking lots that can handle Thanksgiving weekend shopping but are not fully used throughout the rest of the year. Or, the highway that needs more and more lanes to handle rush hour traffic while there are many hours when that capacity is not needed. Sewers need to handle really big storms or events. But, in each case, can the largest need be forecast correctly? Adding lanes to roads can increase the traffic. Right-sizing parking lots can be tricky. And planning for the rare storm is hard, particularly if conditions are changing. Similarly, people will not be happy in these cases if there is not enough capacity and there will be calls to fix the problem afterward.

Rebuilding beachfront McMansions

Posted on by

A journalist argues the construction and reconstruction of large homes near Atlantic beaches is a losing proposition in the long run:

Through federally funded flood insurance, huge appropriations for beach nourishment projects, and generous, well-intended relief aid, government policy allows developers and wealthy investors to build huge houses and hotels on beachfronts and low-lying barrier islands at high risk from coastal flooding as well as hurricanes. Uncle Sam’s generosity makes it all possible…

Writing just as the extensive damage from Hurricane Florence became apparent, Gaul covers the waterfront, so to speak — from Hurricane Katrina to South Florida, to the halls of Congress. In North Carolina, he stops Down East in Columbia, Creswell and other towns of North Carolina’s “Inner Banks,” where rising water levels and flooding are washing away entire communities…

According to Gaul, things began to tip in the 1980s, when multistory “McMansions” began to supplant the simple Cape Cods. (A similar trend has transpired on the north end of our state’s Outer Banks). Disasters such as the Ash Wednesday flood of 1962 did little to discourage development. On the contrary, real estate dealers saw storms as “clearing the market,” blowing down older, ramshackle structures and making way for the new, bigger units that buyers seemed to want.

Real estate prices went up, and increasingly retirees and residents with modest incomes were squeezed out. But there were always more customers in line for resort property.

I wonder if the primary objection is that big homes are being built and someone is profiting from the government money or should there be no homes on these properties? If the goal is to protect the beach and taxpayer dollars, less development in these areas is better. If the problem is profiting with the government’s money, there could be restrictions on the size of the new home or how the money is used.

It would be an interesting thought experiment to consider what this would look like without any government intervention. The argument here is that the government’s funding for rebuilding simply encourages the cycle of building larger and larger homes. If there were no regulations, what would the market bear? Or, as the author seems to suggest, would different regulations be better for the long-term fate of the beach and tese communities?

The correct interpretation of the concept of a 500 or 1,000 year flood

Posted on by

A flood expert addresses five myths about floods and this includes the idea that a 500 year flood only happens once every 500 years:

Myth No. 3
A “100-year flood” is a historic, once-in-a-century disaster.

Describing floods in terms of “100-year,” “500-year” and “1,000-year” often makes people think the disaster was the most severe to occur in that time frame — as encapsulated by President Trump’s tweet calling Harvey a “once in 500 year flood!” He’s not alone. When researchers from the University of California at Berkeley surveyed residents in Stockton, Calif., about their perceived flood risk, they found that although 34 percent claimed familiarity with the term “100-year flood,” only 2.6 percent defined it correctly. The most common responses were some variation of “A major flood comes every 100 years — it’s a worst-case scenario’’ and ‘‘According to history, every 100 years or so, major flooding has occurred in the area and through documented history, they can predict or hypothesize on what to expect and plan accordingly and hopefully correct.”

In fact, the metric communicates the flood risk of a given area : A home in a 100-year flood plain has a 1 percent chance of flooding in a given year. In 2018, Ellicott City, Md., experienced its second 1,000-year flood in two years, and with Harvey, Houston faced its third 500-year flood in three years.

That risk constantly changes, because of factors such as the natural movement of rivers, the development of new parcels of land, and climate change’s influence on rainfall, snowmelt, storm surges and sea level. “Because of all the uncertainty, a flood that has a 1 percent annual risk of happening has a high water mark that is best described as a range, not a single maximum point,” according to FiveThirtyEight.

I am not surprised that the majority of respondents in the cited survey got this wrong because I have never heard it explained this way. Either way, the general idea still seems to hold: the major flooding/storm/disaster is relatively rare and the probability is low in a given year that the major problem will occur.

Of course, that does not mean that there is no risk or that residents couldn’t experience multiple occurrences within a short time period (though this is predicted to be rare). Low risk events seem to flummox people when they do actually happen. Furthermore, as noted above, conditions can change and the same storms can create more damage depending on development changes.

So if this commonly used way of discussing risk and occurrences of natural disasters is not effective, what would better communicate the idea to local residents and leaders? Would it be better to provide the percent risk of flooding each year?

McMansions lead to water runoff damage in Kirkwood, Missouri

Posted on by

The construction of new housing can lead to water issues for existing homeowners. See the ongoing case of Kirkwood, Missouri homeowners dealing with more water due to the construction of McMansions:

Next week, a new Kirkwood water runoff regulation will take effect, but longtime residents say it’s all too little too late…

Like many other longtime Kirkwood residents, Liskew said water began invading her home when new construction started near her neighborhood. Behind her home, she noticed new, large homes—often called ‘McMansions’—were being built on small lots…

That special council created a new storm water management regulation. The ordinance requires all “infill development” to capture rainfall runoff, and submit a plan to the Metropolitan St. Louis Sewer District for review and approval prior to the issuance of any building permits…

And she said it’s been an expensive, never-ending problem to worry about. In addition to several French drains, Liskew has installed a sump pump, taken out basement windows, graded a large portion of her yard and even commissioned a water runoff study to find out where the water was originating. The study found the water was coming from the neighborhood directly behind her home, and heading directly into her backyard.

See an earlier blog post on the Kirkwood situation. To some degree, the construction of any new residential units is likely to affect water runoff. Switching land from non-use or agricultural use to homes, driveways, yards, and streets will have an effect. Add to that the pejorative term McMansions used here: big homes take up more space and in the interest of keeping water away from them even more water is channeled elsewhere.

I sometimes wonder if the way water issues in suburbia work is like this: every new development attempts to push the water somewhere else and the problem simply moves onto someone else’s property. Generally, developers and municipalities do their best to move the water away from existing buildings and uses but this may not be possible depending on the topography and existing infrastructure. Cleaning up the water issues after the fact – such as in Kirkwood or the Deep Tunnel project in the Chicago region – is costly and very frustrating. But, without a commitment to avoid sprawl or widespread adoption of greener techniques, the water problems will just get pushed down the road. Flooding will continue to be a major suburban problem.

Deep Tunnel as the wrong solution to water issues (plus alternative uses)

Posted on by

Henry Grabar poses an interesting question: what if the Deep Tunnel project, one of the largest civil engineering feats in the world, does not solve flooding and stormwater issues in the Chicago region?

What if Chicago took a wrong turn in 1972 when, in the spirit of civic grandee Daniel Burnham (“Make no little plans”), it opted to build the world’s largest sewers instead of making all possible efforts to keep rainwater out of them? Scott Bernstein, the founder of the Center for Neighborhood Technology, says that the Deep Tunnel imposed a massive opportunity cost because the city and the district did little else to adapt. The MWRD spent billions on what engineers call “gray infrastructure” (pipes, tanks, pumps) and virtually nothing on “green infrastructure”: rain barrels, detention ponds, green roofs, porous pavements, and other adaptations that would have kept water out of the system…

The project proceeded regardless. Even with downsized reservoirs and a longer time frame, Chicago’s ambition captured the attention of civil engineers around the world. Today, most U.S. cities whose combined sewer overflows are governed by consent decrees with the EPA are working on Chicago-style digs. St. Louis, which has the fourth-largest sewer system in the country, is under a consent decree to commit $4.7 billion to ending its overflows through deep tunnels…

While engineers’ penchant for megaprojects endures, some American cities are preaching deterrence. If Chicago built a bathtub, Philadelphia is trying to transform itself into a sponge with park space, street trees, and permeable pavement. The city is spending $2.4 billion to implement the nation’s largest green infrastructure plan, an experiment that positions it as the anti-Chicago. The city thinks keeping water out of the system will save billions of dollars compared to a rejected tunnel proposal—and that green initiatives will produce positive externalities, like improving air quality and creating verdant streets.

In Chicago, meanwhile, the MWRD has committed to creating just 10 million gallons of green infrastructure capacity under its EPA consent decree. Compare that to neighboring Milwaukee, a deep-tunnel city that now believes its green infrastructure will, by 2035, surpass the capacity of the tunnels and hold up to 740 million gallons of rain where it falls.

Hindsight may always be a little tricky in these cases as we have the advantage now of being able to see the Deep Tunnel project in action. Does it actually accomplish its goals? Was all the spent money worth it? At the same time, a project of this magnitude should have generated plenty of discussion and at least a few alternative options.

If Deep Tunnel does not work as intended or does not solve all of the flooding and stormwater problems, I wonder if it could be used in other ways. I’m thinking of other major infrastructure projects that have been reversed or reused, like urban highways that are torn out (like in Boston or San Francisco) or former railroad lines turned parks or recreation areas (think the High Line). Some other options for the Deep Tunnel:

  1. Underground roads. With Elon Musk’s Boring Company working on underground roads plus Chicago’s legacy of Lower Wacker Drive, perhaps traffic could be rerouted deep underground.
  2. Underground freight movement. Given Chicago’s railroad bottleneck, this could be an interesting solution.
  3. An underground park and recreation area. It would certainly be unique. Think a combination of spelunking, rock climbing, and exploration.
  4. A military installation and testing area.