Practical Engineering

If all the earth was solid rock, life would be a lot simpler, but maybe a lot less interesting too. It is both a gravitational necessity and a source of job stability to structural and geotechnical engineers that all construction - great and small - sits upon the ground. And the ways in which we accomplish such a seemingly unexceptional feat are full of fascinating and unexpected details.

In some cases, it just stops being feasible to chase the slope of a sewer farther and farther below the ground surface. A good alternative is to install a pumping station that can lift raw sewage from its depths back closer to the surface. Lift stations can be small installations designed to handle a few apartment complexes or massive capital projects that pump significant portions of a city's total wastewater flow.

We often use chemicals, filters, and even gigantic colonies of bacteria to clean sewage on such a massive scale, but the first line of defense in the fight against dirty water is usually just gravity.

I went around San Antonio filming a few of my favorite infrastructure projects.

In both wastewater treatment and fermentation, humans co-opt microorganisms to convert a less desirable liquid into a better one. This video explores the secondary wastewater treatment process through the lens of homebrewing.

It is undoubtedly unintuitive that water flows in the soil and rock below our feet. This video covers the basics of groundwater engineering, including how wells are built, how injection wells work, and how aquifers interact with surface water features.

Sewers were one of the earliest and most impactful advents of public health in urban areas, and it’s exciting that we’re still finding new ways to use them to that end.

Next time you see a dam, retaining wall, caisson, or any other subsurface construction, there’s a good chance that engineers have had to consider how groundwater will affect the stability. Even though you’d never know they’re there, some combination of drains and cutoffs were probably installed to keep the structure (and the people around it) safe and sound.

Over the past 6 years of reading emails and comments from people who watch Practical Engineering, I know that parts of heavy construction are consistently misunderstood. So, I pulled together a short list of the most common misconceptions. Hope you don't mind just a little bit of ranting from me ;)

Like laparoscopic surgery for the earth, horizontal directional drilling (or HDD) doesn’t require digging open a large area like a shaft or a bore pit to get started. Instead, the drill can plunge directly into the earth’s surface. From there, horizontal directional drilling is pretty straightforward, but it’s not necessarily straight. In fact, HDD necessarily uses a curved alignment to enter the earth, travel below a roadway or river, and exit at the surface on the other side.

People use water at more or less a constant rate and yet, mother nature supplies it in unpredictable sloshes of rain or snow that can change with the seasons and often have considerable dry periods between them. If the sloshes get too far apart, we call it a drought. And at least one study has estimated that the past two decades have been the driest period in more than a thousand years for the southwestern United States, leading to a so-called “mega-drought.”

Metals are so necessary and important to modern society that we’ll never escape the problem of corrosion, but the field of corrosion engineering continues to advance so that we can learn more about how to manage it and mitigate its incredible cost.

In June of 2022, many tourists and residents of the Yellowstone National Park area found themselves at ground zero of a natural disaster. Torrential rainfall in Wyoming and Montana brought widespread flooding to the streams and rivers that flow through this treasured landscape and beyond. How will the National Park Service Rebuild? Hasty engineering of large infrastructure can be extremely damaging to natural systems like those in Yellowstone, and you don’t want to invest millions of dollars into repairs that might be subject to similar flooding in the future. After all, we build parks (and roads to parks) to get closer to the natural environment and all its wildness, and there’s almost nothing more natural or wild than a flood.

Making a structure last as long as possible before it needs to be replaced isn’t just good stewardship of resources. It’s a way to keep the public safe and prevent environmental disasters too. Corrosion is one of the number one ways that infrastructure deteriorates over time, so cathodic protection systems are an essential tool for keeping the constructed environment safe and sound.

In July of 2022, the Texas Department of Transportation issued an emergency suspension of work on the half-finished Harbor Bridge project in Corpus Christi, citing serious design flaws that could cause the main span to collapse if construction continues. Since then, they have continued a very public feud with the contractor that is far from resolved. This video explores some of the alleged design flaws and discusses potential next steps on the bridge project.

Even within the field of corrosion engineering, coatings are a major discipline with a large body of knowledge and expertise spread across engineers, chemists, inspectors, and coatings contractors, all to extend the lifespan and safety of our infrastructure.

The Sanibel Causeway was rendered completely impassable to vehicles. Less than a month later, it was open to traffic.