Water Source and Quality
Wastewater is defined as any water negatively affected in quality by human use, usually due to domestic and industrial applications. When people think of waste, a potential source for water is not the first thing that usually comes to mind; however, wastewater has the potential to alleviate a significant amount of water stress in the west. Water reuse is particularly attractive in the situation where available water supply is already overcommitted and cannot meet expanding water demands in a growing community (Asano, 2007). Setting up effective wastewater treatment systems would not only increase our supply to meet future demands, but also help to alleviate major point source pollutions from factories and septic tanks, by enabling us to reuse wastewater rather than releasing it into natural water sources.
One of the main obstacles to effluent utilization is the concern for water quality. The presence of pharmaceutical waste in influent is becoming a major issue as current waste treatment technologies are incapable of fully removing this waste. Although reclaimed water quality is regulated by the U.S. Environmental Protection Agency, the public is not fully confident about the usage of treated waste water (Asano, 2007). Another obstacle is wastewater treatment costs, as treating one cubic meter of wastewater costs about 89 cents (Hlavinek et al., 2008). The expenses for treating wastewater to a potable quality are even higher.
Despite these challenges, reclaimed water from waste treatment plants is an important alternative water source that can be reused in a variety of ways. Reclaimed water is being used in irrigation, industry, aquifer recharge, and more. It is important to analyze each of these uses in order to make the best use of this alternative water source (Asano, 2007).
Desalination has been hailed as the solution to our current water problems. However, the implementation of desalination may result in a multitude of problems in the future. Although desalination has been utilized since at least 1861 in South Florida, we have yet to scale desalination to a national level (Tonner, 2002). There are several reasons as to why desalination has not been nationally developed yet. A primary reason is the energy and monetary cost of desalination. It can cost over $1000 to produce 1 acre-foot of desalinated water, whereas with conventional methods, it costs approximately $200 per acre-foot ("Thirsty?" 2008). The cost differential is decreasing with the development of new technology, however, the high production costs along with the costs to maintain a desalination plant prove to be a huge hinderance in a full-scale use of desalination plants across the United States. Another issue that has to be addressed with the construction of desalination plants is the environmental impact that these plants will have on its surrounding area and on the Earth. Desalination plants are extremely energy intensive, which results in greenhouse gas emissions if certain sustainable technologies are not utilized. Former Secretary of State, Treasury, and Labor Shultz spoke recently at an MIT lecture about how this leads to investor hesitancy to support renewable or alternative energy, as business plans, profit, and economic viability can evaporate over a period of months due to changes in the price of oil (from $133 in July 2008 to $50 in November) (Schultz, 2008). This argument also applies to an unstable investment environment for desalination, and makes it difficult to predict what the actual environmental impacts will be. The desalination process itself also generates a significant amount of brine. If not disposed of properly, this brine is capable of raising the water temperature, affecting the sea's salinity and turbidity, and disrupting the marine ecosystems that it comes into contact with ("Thirsty?" 2008). Nevertheless, desalination will be a part of our solution to mitigate the growing water crisis.