April 16, 2013
Environmental Risk: Sacramento-San Joaquin Delta
Introduction
Commonly referred to as the “Bay Delta”, the 1,100 square-mile region lies on the eastern edge of the Bay Area. It gets its name from the merging of the Sacramento and San Joaquin Rivers, which originate in the northern and central mountains of California. When these freshwater rivers meet the San Francisco Bay, they form the largest, and one of the most productive estuaries on the west coast, which is home to half a million people and 300 species of wildlife.
The Problem
The Sacramento-San Joaquin delta has been modified by humans since the mid-1800s, when the Gold Rush sparked a large migration to the area. Those who were unsuccessful at mining tried their hand at farming and found that the soil in this area was rich in organic matter. These farmers built levees to drain the land and built farms that still exist today. But despite large economic gains, their actions destroyed natural habitats and have caused 29 native animal species to become threatened or endangered.
Over the past several decades, the Delta has become the hub of California’s water distribution system. It provides water to over 20 million Californians and supplies one of the largest farming regions in the world, the San Joaquin Valley. Much of the nation’s domestically grown produce comes from water that flows through the Delta, so there is a large economic incentive to divert this water to the Central Valley (Hanson). This diversion is done by pumping stations, which transport freshwater from the rivers into the state and federal water projects. It also changes flow patterns in the channels, which confuses migratory fish. Other factors such as pollution, competition, and predation from nonnative species also add to the environmental risk. It is no surprise that populations of native fish such as the Delta smelt and Chinook salmon are on the decline.
Scientists have determined that the Delta smelt is an indicator species, whose presence or lack thereof demonstrates the quality of an environment. The Delta smelt was placed on the federal endangered species list in 1993 and its population as well as others continues to decline (Healey). The protection of the Delta smelt by the Endangered Species Act has not come without controversy however, with many questioning how preservation of the species justifies reduced water diversion for those who need it.
Drastic changes in the estuary environment can also lead to the extinction of certain plants and animals. Chemical changes can contaminate the freshwater supply and leave large populations without viable drinking water. Fortunately, actions have been taken to remediate this growing problem.
Analysis
During the Gold Rush, one of the strategies used to extract gold from the river was through the use of mercury. Some of this mercury was spilled into the waterways and would eventually flow into the Delta. Other sources of pollution include agricultural runoff, where 200 million pounds of pesticides are applied to California farms every year. The EPA (2013) also reported that large oil refineries along the San Francisco Bay “release more than one million pounds of toxic chemicals”. Some of these chemicals are washed into the Delta and have gone unregulated for more than 20 years (Wren). Dredging in the estuary for water transportation also increases the turbidity of surface waters by temporarily suspending bottom sediments.
Climate change also plays a role in this problem because it will change the water inflow. Much of the water that flows into the Delta comes from the melting of the snowpack, so warmer temperatures would lead to less spring runoff (California Department of Water Resources). The lack of water coming into the Delta affects the reservoirs that release water for human use and agricultural use, spelling trouble for many Central Valley farmers.
The projected sea level of the San Francisco Bay is also expected to rise with warmer temperatures. Most of the islands in the Delta are surrounded by levees that are only 10 feet in height and constructed mainly of dirt. During storm events, the influx of water from the Bay may be strong enough to break levees and lead to widespread mixing with saltwater (Hanson). These levees can also break in the event of a major earthquake, which is already overdue in California.
Lastly, invasive species threaten the well-being of those native to the area. When a new species is introduced to an area, it will proliferate with lightning speed because there is no competition that will limit its population growth (The Green Gate). Hundreds of aggressive species have found a home in the Delta ecosystem and they are leaving little room for native plants and animals. This further worsens the problem of the endangered species and presents new challenges for the human population.
Exposure Analysis
Nutrient concentrations are significantly correlated with changes in components of the food web over time (Glibert). The ammonia (NH4+) that is discharged from sewage treatment plants affects phytoplankton assemblages. This is directly related to zooplankton, clam abundance, and ultimately the population of various fish species such as the Delta smelt. Phytoplankton constitutes much of the diet of primary consumers and this effect will be felt across the food web. The figure below depicts this correlation, where higher concentrations of ammonia lead to a decrease in the number of Delta smelts.
Changes in salinity and temperature also affects the Delta smelts because it needs suitable conditions for its young to grow. We can see from the graphs below that eggs are the most vulnerable to environmental changes due to their low tolerance of high salinity (Glibert). In a warmer world, fewer eggs will be able to survive because temperatures and salinities will be out of their comfort zones. They may not be able to adapt quickly enough to these changes and will likely face extinction. Other plant and fish species face similar threats.
There are always uncertainties when it comes to predicting how species will respond to changes in habitat quality (Healey). Models try to account for each aspect, but the amount of variables and measurements needed to produce a perfect simulation is near impossible given the large area of the Delta. Instead, researchers tend to gather small sets of data, analyze those results, and apply their findings to the whole population.
Conceptual Model
Bay Delta Conservation Plan (BDCP)
A proposed conservation plan, which would operate over the next 50 years under the Endangered Species Act, intends to both promote local species populations (including the Delta smelt) while simultaneously ensuring the availability of freshwater for decades to come. But a report released by the National Research Council in the spring of 2011 discredited much of what the plan intended, claiming “the independent scientists assembled by the NRC found that the BDCP fell well short of an objective analysis of likely impacts of the Plan,” (National Research Council).
Currently, the BDCP is working to update its plan in light of criticisms it received. A new Environmental Impact Statement has been filed, and documents concerning the project are currently up for public review, available at: baydeltaconservationplan.com
Minh Ngo and Austin Reagan
Works Cited:
Hanson, Charles. “Delta Risk Management Strategy”. Jack R. Benjamin & Associates, Inc. Department of Water Resources. 2006.
California Department of Water Resources. “Progress on Incorporating Climate Change into Management of California’s Water Resources”. July 2006.
National Research Council. “Draft Bay-Delta Conservation Plan: National Research Council Review Validates the Bay Institute’s Concerns.” May 2011.
The Green Gate. “Invasive Species”. Natrual Resources Defense Council. 2001. http://www.nrdc.org/greengate/wildlife/invasivef.asp.
Wren, Ian. “EPA Report Details Toxic Discharges from Big Industry”. San Francisco Baykeeper. 29 Jan 2013. http://baykeeper.org/blog/epa-report-details-toxic-discharges-big-industry.
Healey, M.C. et al., “Conceptual Models and Adaptive Management in Ecological Restoration: The CALFED Bay-Delta Environmental Restoration Program”.
Glibert, Patricia. “Long-term changes in nutrient loading and stoichiometry and their relationships with changes in the food web and dominant pelagic fish species in the San Francisco estuary, California”. Fisheries Science Vol. 18, Iss. 2, (2010).
March 1, 2013
The Indecisive Relationship Between LA and Water
Throughout Los Angeles’ lifetime, water has been a source of conflict, growth and severe economic anxiety. In 1979 when the city was initially founded, one of the first anthropogenic effects of humans on the natural world was the damming of the Los Angeles River. Progressively canals were added to aid irrigation of crops, further diverting enormously wasteful quantities of water for agricultural purposes.
As the population began to grow exponentially, Los Angeles residents began to realize that the state of their water availability was at risk. Understanding and prefacing a colossal loss of vital water supply and resources, William Mulholland and Fred Eaton united and decided that buying out the Owen’s River was the best solution to this crisis. Consequently, Mulholland and Eaton began purchasing land along the river until finally using it to construct the LA Aqueduct in 1908, which they proposed would serve as a reliable source of water for Los Angeles forever.
Unfortunately, Mulholland could never have predicted the quantity people that migrated to the Los Angeles area under such a short period of time and by 1941, four of seven streams that lead into the Mono Lake had been tapped into, depleting precious resources. These large-scale changes to water supply drastically altered the natural environment as well as the water-consumption mentality of citizens. Over recent years the situation for the environment has worsened; various animal species are under risk of becoming endangered due to habitat destruction and depletion, and humans are once again suffering with the question of what to do about water scarcity.
Thanks to the efforts of people such as Mulholland, less than 30 years later the city of Los Angeles had invested over a quarter billion dollars into its water supply (Washington Post Source). As a result, Los Angeles is in a relatively positive state with regards to water. However, this does not suggest that we relax and seize to improve conservation efforts and quality of water resources.
There is currently very limited public awareness of Los Angeles’ alternative options to water sources. The proportion of water taken from the LA Aqueduct(Sierra Nevada Watershed) has been reduced with drought. Water difference is taken from the Metro water supply, which originates from the Sacramento/ San Joaquin Delta and Colorado River. (Securing L.A.’s water supply).
How long will each of these sources last? The Los Angeles Aqueduct relies on the snowpack runoff of the Nevadas, which is not necessarily guaranteed to be consistent each year, considering the average increase in temperature associated with global warming.
Why are we currently faced with such an unsustainable water supply? We are breaking the surface with research and conservation efforts, but we could be improving significantly. According to the Mayor’s Report in the LADWP, water usage has remained the same over the past 25 years, though population has continued to increase. This is due largely to strict water regulations that have been set in place after the drought of 2007.
Los Angeles can benefit most successfully by transitioning to more non-traditional water sources, such as rainwater capture and water recycling. Though these resources are readily available, they are not widely accepted in our culture. A journal from the Water Pollution Control Federation mentioned that demand for potable water has been reduced by 20% and is slowing decreasing annually. A shift to a more environmentally conscious mindset however will only occur when the population’s attitudes towards new water sources alter positively, which looks promising.
By: Stephanie Whyte & Clayton Greene
Bibliography
Villaraigosa, Antonio R., Mayor. “Securing LA’s Water Supply.” City of Los Angeles. City of Los Angeles Department of Water and Power, May 2008
“History of the LA Aqueduct.” History of the LA Aqueduct. City of Los Angeles Department of Water and Power, n.d. Web.
“Los Angeles Counts Water Supply Cost At Quarter Billion.” The Washington Post. The Washington Post, 02 Mar. 1934. Web.
Cornielle, Richard. “Master Planning a Water Reuse System.” Water Environment Federation. (Water Pollution Control Federation), 1985. Web.
April 22, 2012
If You’ve Drank Water Today—Consider Yourself Lucky
The United Nations has declared water a basic human right, saying that “the human right to water entitles everyone to sufficient, safe, acceptable, physically accessible and affordable water for personal and domestic uses.” Many hold similar views as the UN, while others differ in opinion and think water is a privilege not a right. As the human population increases alongside the demand for clean, safe sources of water, this issue will only escalate in significance and severity. Humanity as a whole must answer the question: Is water a privilege or a right?
Currently access to safe drinking water is not universal. With almost 900 million people lacking access and more than 1.5 million children annually dying due to this reason, the United Nations has recognized clean water and sanitation as “integral to the realization of all human rights.” Providing access to drinking water does not have a simple solution; when dealing with the right of humans to access water: political, social, economic, and industrial changes are needed. At the 2011 United College London (UCL) Annual Conference, the issue of water security was brought up and concluded that the global North cannot simply expect the South to generate access to clean drinking water. For the most part water abuse comes from the North and the South is the region in need of more clean drinking water. Many believe the global North should treat water as a commodity since they tend to overuse water and are not penalized for doing so. With this implementation, water may be better conserved in the North which may help the South receive economic deductions to increase clean water access.
Many take the opposite view on this issue, arguing that water is a privilege and treating water as such does not violate basic human rights. Specifically, some take the stance that water is a simple human need, not a right we all hold. One argument that supports this stance is water privatization. Some believe that the government should not hold the responsibility for providing adequate water to its civilians. Because the privatization of water has been successful before, where companies control the supply and accessibility to water, people cannot assume they are entitled to clean water without paying a price. Also, it is arguable that the number of people living in the world today without access to clean drinking water is proof enough that water is a privilege not a right. History has shown that many people do not have access to safe drinking water, and this issue will only become more severe as human population increases alongside demand. In fact, the number of people currently without access to clean drinking water totals the number of people living in the US, Canada, Argentina, Chile, Singapore, United Arab Emirates, France, Germany, England, Italy, Spain, Japan, Australia and Norway. Thus, critics argue that water is a privilege, because it is not sustainable to treat water as a right where it will become more difficult to supply as we progress into the future.
For those who see water as a privilege, their idea generally revolves around keeping sustainability of the resource. We see water being abused daily through agriculture and private consumption. According to Maslow’s hierarchy of needs, water is a basic physiological right that is essential for survival. Allowing people access to clean drinking water would not set up a system of abuse, but would rather create a need for stricter guidelines. Fracking for example could become a safer practice after the creation of more regulation, because the risk of water source contamination would decrease as water quality and technology improve. If water is granted to everyone, we would see a growing need for protection. Consequently, the enforcement of stricter guidelines and policies would be needed to ensure the well-being of mankind.
Connor Schroeder and Albert Perez are undergraduates in the USC Dana and David Dornsife College of Letters, Arts and Sciences.
March 19, 2012
CAFOs: Contaminants, Animals, Feces, Odor
Some critics would argue that feedlots are required by society in order to keep up with the growing population and increasing demand for food. Even though this statement is debatable, the real question is whether or not feedlots are worth the environmental risk? Specifically, Concentrated Animal Feeding Operations or CAFOs pose an extremely high risk to the environment with their impact on air, water, and land quality.
Water quality is heavily affected by the discharge and waste that comes from thousands of animals confined on a small farm. Often, companies deal with manure and urine from livestock by channeling it into a lagoon or cesspool. The risk of a tear, leak, or break is highly probable at feedlots. Pollution in the form of nitrates, microbes, pathogens, pharmaceuticals, and many more are flooded into nearby water systems and threaten human health, not only the environment. High levels of nitrates, for instance, can increase spontaneous abortions and increase the risk of blue baby syndrome—a disease that causes infant deaths. Antibiotics are heavily used in CAFOs and when those enter our drinking water, it makes it more difficult for us to effectively combat bacteria that progressively become more genetically resistant. The risks of CAFOs are high as not only water is threatened, but the overall environment’s health is compromised.
Contrary to what one might expect, air quality is also at risk due to the broad impact CAFOs have on the environment. Specifically, many hazardous gases are emitted from CAFOs as biological material biodegrades. Methane, ammonia, and hydrogen sulfide are just a few of the gases that pollute the air. Also, cow burps and flatulence produces about one-quarter of the methane released in the USA each year, further contributing to the contamination of our atmosphere. If there is any hope in reducing the risk associated with CAFOs in order to make them a more viable option for livestock farming, society must address the growing air quality issue associated with them.
Any land used by CAFOs immediately faces threats to its quality. Manure is one of the biggest threats to soil quality, and the process of over-fertilization of land causes nitrogen and phosphorus levels within soil to become imbalanced. With these imbalances, the threat of leaching or runoff into groundwater greatly increases. This runoff contains bacteria found in manure but also contains the chemicals and substances given to livestock. In fact, most feedlot runoff is high in salinity and can leave behind salt deposits, which causes farmers to use even more water which is then exposed livestock waste. CAFOs pose an interconnected problem amongst land, water, and air resources which makes the issue difficult to deal with.
After looking at all of the evidence surrounding CAFOs and their operation, one must answer the question posed at the beginning of this post: are feedlots worth the environmental risk? After characterizing and assessing this issue, CAFOs are too hazardous to the environment; consequently, other farming alternatives and actions must be pursued. One solution is through public awareness and participation, where consumers purchase meat that has been produced exclusively by farms practicing sustainable farming. Other solutions are alternative farming practices and new technology. Specifically, the government should promote pollution reducing efforts by farmers and further regulate dangerous practices that can impact the environment. If society and the government both advocate for change, the environmental impact of CAFOs can be greatly reduced. If this were to occur, the environment would not only benefit but humans would as well.
Connor Schroeder and Albert Perez are undergraduates in the USC Dana and David Dornsife College of Letters, Arts and Sciences.
February 27, 2012
California Desertification: Too Dry or Not Too Dry
Desertification is defined as the deterioration of land in typically arid areas due to changes in climate and human activities. In the United States, desertification is typically caused by poor farming practices and the conversion of grazing areas to cropland. Climate change intensifies desertification in arid areas because not only are global temperatures rising and natural disasters becoming more extreme, but also the global water cycle and precipitation patterns are such that rainfall is decreasing in most areas and concentrating in a few others. Furthermore, because California is in a climactic region that can be defined as dry subtropical, the effects of climate change and agriculture has led to increased desertification. The short-term and long-term effects of this desertification are numerous and will have many repercussions for both humans and the environment.
The environmental costs of desertification are quite serious and can eventually destroy natural ecosystems. Topsoils lose their fertility and the growth and support of organic life in the pedosphere becomes much more difficult. As topsoil drys out it becomes susceptible to movement from winds, creating new natural disasters such as the Dust Bowl of the 1930’s. Furthermore, this dust can be blown out into the ocean and can affect weather patterns. In order to salvage lands affected by desertification, farmers begin to invest more in irrigation, which in turn diminishes groundwater resources and is the beginning of long-term impacts such as drought and famine. Additionally, as the topsoil becomes less nutrient rich from desertification plants become less productive and many of the ecosystem services they were providing are diminished.
Unfortunately, California becomes more susceptible to desertification there is a tendency to focus only on the immediate effects. Important long-term impacts on the environment also need to be addressed, such as the effects on the carbon cycle, biodiversity, and freshwater supply. Vegetation in arid areas stores a substantial amount of carbon (about 30 tons per hectare) and when desertification causes drought and the vegetation dies, that storage is lost. In addition, desertification dries out soil, the organic matter of which is the largest known carbon sink, resulting in increased greenhouse gas effects as that carbon is released into the atmosphere. As soils and vegetation are affected by desertification, ecosystems lose key resources that result in a loss of biodiversity. Desertification also poses a threat to freshwater resources. River flow rates decrease, leading to silt build up in estuaries, which incites saltwater intrusion into the water tables. As the demand for water increases there is a tendency to over-pump aquifers, which can result in water depletion and land compaction. For example, the San Joaquin Valley of California experienced subsidence at a maximum of 28 feet between 1925-1970 from overdrawn aquifers. Because California relies so much on agriculture, farmers exploit aquifer water for irrigation without considering these long-term issues. However, if the agricultural industry were to collapse from drought, we’d be facing the threat of famine and a huge economy crash.
Clearly there are many negative effects from the process of desertification that need to be addressed. Some of the most popular decisions to combat the effects of the land drying out include sustainable farming practices, such as drip irrigation, integrated crops, or no-till farming, and drought prevention. As stated in the 2010 California Drought Contingency Plan, “California’s water resources have been stressed by periodic drought cycles and unprecedented restrictions in water diversions from the Sacramento-San Joaquin Delta in recent years. Climate change is expected to increase extreme weather. It is not known if the current drought will abate soon or if it will persist for many years. However, it is certain that this is not the last drought that California will face.” The DCP has moved towards enhancing monitoring and early warning capabilities, assessing water shortage impacts, and creating preparedness, response, and recovery programs, which should help California to conserve water and slow down the desertification process.
Sources:
http://www.waterplan.water.ca.gov/docs/cwpu2009/0310final/v4c06a01_cwp2009.pdf
http://pubs.usgs.gov/circ/circ1182/pdf/06SanJoaquinValley.pdf
http://www.fao.org/sd/EPdirect/EPan0005.htm
http://onlinelibrary.wiley.com/doi/10.1111/j.1468-5973.2010.00633.x/full
Harriet Arnold and Divya Rao are undergraduates in the USC Dornsife College of Letters, Arts and Sciences.