The Consequences of Wetland Drainage

In the 1660’s there was over 220 million acres of wetlands in the United States. Since then, over half have been destroyed. Wetlands act as a natural flood control and water filter, not to mention the biological diversity they contain; therefore, destroying them is like destroying part of our country. Civil Engineers have the ability and responsibility to stop the wetland destruction and reverse the effects.

Source: http://www.soil.ncsu.edu/publications/

The U.S. Environmental Protection Agency defines wetlands as “those areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, prevalence of vegetation typically adapted for life in saturated soil conditions.” Wetlands include swamps, bogs, fens and marshes; all of which have biologically diverse ecosystems. As I mentioned earlier, wetlands provide a wide variety of useful functions. First, they operate as a water purification system. Wetlands allow water to filter out impurities so only clean water is added to the groundwater. Second, they provide a habitat for fish, wildlife and a variety of plants. Third, wetlands control flood waters and snow-melt  which they slowly release there-after. This provides a level of stability along coastal regions. So, as you can see, wetlands are a very valuable part of nature that needs to be preserved.

Source: http://mhsapeses4th.wikispaces.com/

Despite the benefits that wetlands provide, they are being drained and destroyed at an alarming rate. The top cause for their disappearance is wetland drainage. Wetland drainage is the act of removing the water from low-lying areas to convert the land for use in agriculture or housing. This kind of action is having and will have worsening consequences. Due to the removal of the water, groundwater isn't being replenished as efficiently and will start to undergo something known as groundwater mining. Groundwater is important because it is the source of drinking water for over 50% of the people in the U.S. Additionally, toxic compounds (such as urban and rural runoff) won’t get filtered out as well as if there were wetlands. This has the possibility of contaminating groundwater and making it unusable. Furthermore, wetlands are an effective way of controlling snow-melt and flooding. Without the wetlands, communities will be subject to repeated floods. Finally, wetland drainage has caused many species to become endangered (like the ­­­­­­black-faced spoonbill) or to even go extinct (like the pink-headed duck). This means wetland drainage is extinguishing the possibility of large-scale diversity.

Source: http://cooperativeconservation.org/

The U.S. government is doing research to try and reverse the effects of wetland drainage. Civil Engineers can help by participating in projects, like wetland restoration, which are taking place all across the U.S. Wetland restoration is done by initially flooding the land and over time the wetland vegetation will reestablish itself. However, bringing back lost wetland is not always that simple. Much of the area that used to be wetland was converted to agriculture which causes the soil to lose a lot of it nutrients, while also being changed by the application of fertilizers and pesticides. Therefore, as Write states, "the proper management of hydrologic conditions and vegetation are critical for reestablishment of wetlands." This is the perfect job for geotechnical and environmental civil engineers. 

So, as you can see, wetlands are a vital part of nature. They help us in countless ways and are essential to our society. Though the loss of wetlands has slowed over the year, the number of acres is still decreasing. It's up to civil engineers to stop wetland drainage and reverse the negative effects.

Source: http://www.fws.gov/kulmwetlands/wetlands.html 

Nanotechnology: The Path to the Future

Nanotechnology isn't new; what is new is the way that it is being used. Nanotechnology is currently being studied to figure out how it can be applied to civil engineering. There are a number of areas that it can be applied to, and its potential applications are endless. As it says in the NBM Media article, nanotechnology “offers better built, long lasting, cleaner, safer, and smarter products.”

Source: http://thedakepage.blogspot.com/2010/06

A nanometer is one billionth of a meter; that is very, very tiny. It turns out that if materials are manipulated on that small of a level, there are huge benefits. For instance, carbon nanotubes (CNT), which are tubes that have a diameter of one nanometer and a length of several millimeters, can increase the strength of steel by five times. Nanotechnology can also improve other areas, such as with the use of titanium dioxide (TiO₂). When added to paint, cement, windows or other mediums, it gives them sterilizing and deodorizing properties. Additionally, TiO₂ becomes hydrophilic when exposed to UV. This quality creates anti-fogging and self-cleaning (which would be especially useful for windows).

Source: www.nanotechbuzz.com

There is so much potential for nanotechnology in the field of civil engineering. Two of the main areas that it is being applied to are concrete and steel; in both, it has led to great increases in strength and durability. In the area of cement, nanoparticles improve the molecular structure, leading to improved properties. If TiO₂ is added, it offers self-cleaning for buildings and signs, which translates to less maintenance. If CNT are incorporated into cement, it increases compressive and flexural strengths, which equates to safer structures. As for steel, nanoparticles lower the unevenness of the surface. This causes a decrease in the amount of fatigue cracking in structures like the frames of bridges and buildings. When CNT are added to steel, it creates stronger cables, which will result in a lower cost and shorter construction time. Overall, “advancements in this technology would lead to increased safety, less need for monitoring and more efficient material use,” according to Niranjana.

The drawback of nanotechnology is its cost. Nanotechnology is so small that it is difficult to manufacture; thus, it is not cheap. Like any new technology, it's expected to initially be expensive, but as time progresses and we learn more about nanotechnology, the price will become more reasonable.

This type of technology will lead to great improvements to society. The only limit for application of nanotechnology is our imagination. Nanotechnology can lead to the creation of all of the following:

Source: http://www.secureglass.com.au/tag/

       ·    Self-cleaning windows on tall buildings

       ·    Sidewalks and walls that don’t dull in color

       ·    Street signs that never get dirty

       ·    Bridges that repair themselves

       ·    Steel cables that are tougher

       ·    Paint that insulates and repels water

       ·    Concrete that is more durable

And the list could go on. However, to make all of these a reality, the proper research has to be done. Engineers have already made vital headway in the study of nanotechnology. The next step is to bring it to life. Therefore, it is imperative that civil engineers have the opportunity to continue the exploration of nanotechnologies and that construction starts to incorporate their use. Nanotechnology has great potential, but we can only make that envisioned future a reality if we are willing to invest in it.

Are High-Speed Rails a Good Fit for the U.S?

Source: http://m24digital.com/en/2010/10/26

Transportation is becoming a big problem in the US. Things like grid-lock and CO₂ emission are more prevalent than ever before. One solution to this (that is very effective in Europe) is the use of high-speed rails. Many civil engineers are looking at how this technology can be adapted for use in the United States.

High-speed rails are passenger trains that reach speeds of over 200 mph. There are two types of high-speed railways: magnetic levitation (aka: maglev) and conventional. There are advantages and disadvantages to each. The maglev is the ideal high-speed rail. It travels faster, doesn't run on fossil fuel, is more quiet than conventional railways and requires less maintenance. So why don’t we go with maglev? Mostly because it costs a lot more; the maglev would need an entirely new set of tracks. Although the conventional high-speed rail wouldn't reach speeds as high as the maglev, it could run on the current network of railroad tracks. It would simply share "existing passenger rail services and freight services."

Source: http://soulofamerica.com/interact/soulofamerica-travel-blog

Europe has invested in a highly effective upgrade in transportation. They have laid out a network of high-speed railways, some of which run through multiple countries. One of the main reasons high-speed rails are so effective in Europe is because of how the population is laid out. Most of the population is in big cities and those cities are relatively close to eachother. For this reason, connecting the cities with high-speed rails becomes easier. Additionally, the high-speed rails are widely accepted by the public because they are easily accessible in the large cities, which makes them convenient to use for daily commutes. In turn, this success encourages more passengers to ride, and has led to a sharp increase in the number of train passengers in Europe. The consequence is fewer people driving, which equates to fewer traffic jams, less fuel consumption and less CO₂ emissions.

The drawback of the United States is that the cities are very spread out. This is known as “urbansprawl.” It is one of the main issues standing in the way of bringing high-speed rails to the US. According to Demographia, U.S. has almost one of third the urban density of Europe, which makes it challenging to build high-speed rails that are accessible to a large number of U.S. citizens. In addition, building the infrastructure for these high-speed rails (i.e., building the tracks) would be a huge initial investment; it is estimated to be between $65 and $81 billion. As Samer Madanat puts it: “it will be the largest infrastructure transportation project in the U.S. since the Interstate was constructed.” It has been suggested that the U.S. just uses the railroad tracks that are already built; however, this would create other problems. For example, if we don’t upgrade to the high-speed rail tracks, we won’t be able to reach top speeds. Moreover, the U.S. has one of the best freight railways in the world. If we start converting these tracks into passenger lines, there will be fewer ways to haul freight. The final, major concern is whether or not people will use the high-speed rails if they are built. The reason high-speed rails are so successful in Europe is because so many people use them daily. However, in the United States, this would require a change in lifestyle, and that kind of change will not happen overnight. In order for the high-speed rail to be equally successful in the U.S., they need to be easily accessible by a large number of people that are willing to use them regularly.

Overall, high-speed rails are a great solution to transportation problems; however, it’s just not realistic for the U.S. The population of the U.S. is too spread out and the number of possible passengers is unreliable. Furthermore, it would require an initial investment that might be out of the reach of the United States.