The Compost Cure: a widely applicable and cost effective soil remediation strategy

Brendan 1 3This post is by Brendan Sisombath, a senior Biology major at the University of St. Thomas.

Developing soil remediation strategies is becoming an important undertaking in urban environments. Many urban soils contain high concentrations of contaminants such as polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals such as arsenic, lead, and mercury (McClintock 2012). This presents a concern as ingestion of pollutants via vegetable uptake, contaminated aerosols, and soil adhering to unwashed produce or hands, threaten human health. (Finster et al. 2004, Wortman and Lovell 2013). In many cases, abandoned sites may remain unusable until contaminates are remediated (Hazelton and Murphy 2011). For example, development of the former location of a Ford Plant in the city of Saint Paul cannot move forward until the soil on site meets industrial standards set by the Minnesota Pollution Control Agency (Melo 2014). Current strategies for managing these soils often include removing the soil and replacing it with healthier soil. However, this remains a costly solution and generally only occurs in higher income areas (McClintock 2012, Wortman and Lovell 2013). Forthcoming remediation strategies must be widely applicable and cost effective in order to remain relevant.

The empty 125 acres of land land where the Ford Plant once stood in St. Paul (Pioneer Press: Ben Garvin)

The empty 125 acres of land land where the Ford Plant once stood in St. Paul (Pioneer Press: Ben Garvin)

Application of compost to damaged soils is becoming a widely applicable strategy for soil remediation. Compost improves both chemical contamination and physical degradation in soils, allowing for improvement of many different soils on multiple levels. Application of compost has been shown to reduce bioavailability of lead and other heavy metals (Wortman and Lovell 2013). In addition, compost increases aggregate stability of damaged soil suggesting decreased soil erosion and increased moisture retention (Hazelton and Murphy 2011). Furthermore, the materials to produce compost, both at a large scale and a small scale, are widely available. In cities, approximately one quarter of the food imported is never consumed (Kantor et al. 1997). Food waste and other municipal waste products can be utilized to produce compost for degraded urban soils. There is much potential for members of the community to use their waste products to create compost and contribute to the health of their own soils. Instead of relying on expensive construction projects to be completed, urban communities can create compost and combine it with the contaminated soils to actively work towards their own solution.

In addition, compost is a cost effective remediation strategy. It is estimated that removing contaminated soils and replacing it with healthier soil would cost approximately $130,000 per hectare. Applying and mixing compost with contaminated soils would only cost an estimated $60,000 per hectare (Wortman and Lovell 2013). Furthermore, economic benefits of compost can be expanded when considering its ability to reduce environmental impacts of cities. Composting municipal waste has the potential to greatly reduce nutrient runoff from urban landfills and reduce expensive eutrophication problems. In addition, there is opportunity to use compost to scale up urban agriculture. Plants themselves are also able to remove heavy metals from the soil and store them into its shoot tissues in a process called phytoremediation. This synergetic approach would bolster the remediation power of compost while providing local fo

Developing soil remediation strategies is becoming an important undertaking in urban environments. Many urban soils contain high concentrations of contaminants such as polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals such as arsenic, lead, and mercury (McClintock 2012). This presents a concern as ingestion of pollutants via vegetable uptake, contaminated aerosols, and soil adhering to unwashed produce or hands, threaten human health. (Finster et al. 2004, Wortman and Lovell 2013). In many cases, abandoned sites may remain unusable until contaminates are remediated (Hazelton and Murphy 2011). For example, development of the former location of a Ford Plant in the city of Saint Paul cannot move forward until the soil on site meets industrial standards set by the Minnesota Pollution Control Agency (Melo 2014). Current strategies for managing these soils often include removing the soil and replacing it with healthier soil. However, this remains a costly solution and generally only occurs in higher income areas (McClintock 2012, Wortman and Lovell 2013). Forthcoming remediation strategies must be widely applicable and cost effective in order to remain relevant.

Application of compost to damaged soils is becoming a widely applicable strategy for soil remediation. Compost improves both chemical contamination and physical degradation in soils, allowing for improvement of many different soils on multiple levels. Application of compost has been shown to reduce bioavailability of lead and other heavy metals (Wortman and Lovell 2013). In addition, compost increases aggregate stability of damaged soil suggesting decreased soil erosion and increased moisture retention (Hazelton and Murphy 2011). Furthermore, the materials to produce compost, both at a large scale and a small scale, are widely available. In cities, approximately one quarter of the food imported is never consumed (Kantor et al. 1997). Food waste and other municipal waste products can be utilized to produce compost for degraded urban soils. There is much potential for members of the community to use their waste products to create compost and contribute to the health of their own soils. Instead of relying on expensive construction projects to be completed, urban communities can create compost and combine it with the contaminated soils to actively work towards their own solution.
In addition, compost is a cost effective remediation strategy. It is estimated that removing contaminated soils and replacing it with healthier soil would cost approximately $130,000 per hectare. Applying and mixing compost with contaminated soils would only cost an estimated $60,000 per hectare (Wortman and Lovell 2013). Furthermore, economic benefits of compost can be expanded when considering its ability to reduce environmental impacts of cities. Composting municipal waste has the potential to greatly reduce nutrient runoff from urban landfills and reduce expensive eutrophication problems. In addition, there is opportunity to use compost to scale up urban agriculture. Plants themselves are also able to remove heavy metals from the soil and store them into its shoot tissues in a process called phytoremediation. This synergetic approach would bolster the remediation power of compost while providing local food products to the community, a result that may offset the cost of remediating urban soils.

An elementary school student constructing a compost pile using food waste from the cafeteria. (http://inspiredowl.org/2010/10/25/composting-in-the-lunchroom/)

An elementary school student constructing a compost pile using food waste from the cafeteria.
(http://inspiredowl.org/2010/10/25/composting-in-the-lunchroom/)

The application of compost is a developing remediation strategy that has the potential to improve the quality of urban soils at relatively low cost. Compost can be created and applied without significant expense. This strategy increases the potential for urban cities to remediate its soils and improve living and working environments. However, compost is an appealing strategy to cross environmental justice barriers and provide remediation to underserved areas in urban environments.

Cooling with Food

Ryan 1 2This entry is from Ryan Merry, a senior Biology and Environmental Science major at the University of St. Thomas.

When the weather is scorching hot, which is occurring more frequently due to global climate change, it is human intuition to find refuge under cool shade trees or by refreshing water sources.  Moving beyond human intuition to combat urban heat waves, a new science is developing which investigates how nature’s own cooling systems can be used to mitigate the effects of global warming.  Although this research is still in its infancy, an analysis of to what degree (literally in this case) green spaces can cool the urban environment looks promising and shows that decreases of 0.94° centigrade, or around 2° Fahrenheit, are achievable (Bowler et. al. 2010).  A 2° decrease may not seem substantial, but your heating bill over the entire summer may say otherwise.  Urban greening may also help decrease heat wave disasters such as that in France back in 2003, which had its largest effect in the urban area of Paris and increased the death rate by 147% over the course of the temperature spike (Vandentorren et al. 2004).  Why are urban areas at higher risk during a heat crisis? Bowler et. al. (2010) found that the city’s many heat absorbing surfaces capture the sun’s energy, creating an “urban heat island effect”.  This urban heat island effect creates higher temperatures in urban areas than in the surrounding countryside.  However if green spaces are incorporated into the cityscape, Bowler found mounting evidence that a cooling effect can be achieved in an area within 500 of the green space through shade, mitigation of energy absorbance, and humidity released through plant photosynthesis.  Oak or maple could be used to cool in urban greening, but apple or pear trees can also provide a cooling service with some added produce benefits.

Instead of landscaping to create green spaces in the traditional way, the possibility exists to integrate urban agriculture and urban greening and foodscape the city.  In scientific terms, a foodscape is a study of how food is available to consumers and the effect that has an eating habits (Morgan & Sonnino 2010), but foodscaping would be the conscious effort to integrate more permanent food systems into urban environments.   New foodscape parks could plant (instead of oak tree after oak tree) nut trees such as chestnut or pecans and a wealth of fruits.  This would not only increase the biodiversity of city parks, but provide the services of the other trees (shade, cooling, and recreation) while also providing food at certain times of the year!  There is also not a restriction to food trees.  Foodscapers could incorporate hedges of blueberry or currant, and ponds could become temperature cooling cranberry bogs or fish hatcheries.

Integral to the success of foodscaping would be the perpetual access to these production areas to the public.  Fencing in a foodscaped park and restricting access would deny citizens the benefit of recreation and cooling. However, how could a city possibly manage a landscape that needs care and attention to also produce food under a limited budget?  Could foodscaping ever occur in an urban setting? A group in Seattle Washington has found the answers to these questions, where 30 city parks exist that have fruit trees which are the result of either new community garden plantings or absorption of old “heritage” orchards into the city limits.  Seattle could not afford upkeep of these trees, so a group called City Fruit received a grant from the Washington Department of Natural Resources and U.S. Forest Service to maintain and care for the fruiting trees.  In 2014 the group harvested 8,221 lbs of plums, 6,622 lbs of apples, 4,715 lbs of pears, and 7 other fruits for a total of 22,000 lbs of fruit donated to 39 different Seattle food shelves and all from public city parks.

City Fruit volunteer pruning an urban fruit tree in Seattle, WA.  Picture: http://cityfruit.org/programs/orchard-stewards/

City Fruit volunteer pruning an urban fruit tree in Seattle, WA. Picture: http://cityfruit.org/programs/orchard-stewards/

This Seattle example shows that it is possible and extremely beneficial to incorporate food into green spaces, and it can create the dual benefit of edible production and urban cooling.  Delicious fruit is an easy sell for urban residents, and public interest and volunteering for such projects with a dangling carrot (or perhaps an apple) of fruits for their labor would not be difficult.  My hope in the future is that you can go for a walk in the park to escape the heat of the day and pick a snack for yourself along the way, because why not grow your plum and eat it too?

When form beats function: Plant-scrapers and indoor growing

Kristen 1 4This entry is from Kristen Bastug, a senior Biology major at the University of St. Thomas.

The global agriculture system has benefited from technological advances, and scientists and farmers continue to search for ways to combine technology with agriculture to feed increasing numbers of people. Examples can be seen across the globe: Japan hosts an indoor lettuce farm, vertical farming takes place in Singapore, and hydroponic rooftop gardening can be found in New York. Many countries in Europe, such as Sweden, contain buildings designed with agriculture in mind. These “plant-scrapers,” shown below, serve to produce food and are aesthetically pleasing, attracting outside visitors in a process known as agro-tourism. These innovations are trendy, but trends are not always practical.

Swedish-American company "Plantagon” breaks ground in Linkoping, Sweden with plans to build multiple plant-scrapers in the future. (http://inhabitat.com/plantagon-breaks-ground-on-its-first-plantscraper-vertical-farm-in-sweden/)

Swedish-American company “Plantagon” breaks ground in Linkoping, Sweden with plans to build multiple plant-scrapers in the future. (http://inhabitat.com/plantagon-breaks-ground-on-its-first-plantscraper-vertical-farm-in-sweden/)

Plant-scrapers exemplify a technological advance to the food production system that is an entertaining but unrealistic solution for feeding the world. This is a daunting task in itself, as current food production must double by the year 2050 in order to meet future need (Foley et al. 2011). Plants require soil, water, and sunlight to grow, all of which must be supplied to an indoor setting. The most costly of these is providing enough light, which is passively obtained in an outdoor setting. If vertical farms were used to produce a year’s amount of wheat in the United States, running only the lights would require eight times as much electricity as the nation’s current utilities can supply in a year. This would only free up 15% of the nation’s cropland. Growing corn in the same manner would require 40 times the nation’s energy. Even growing just vegetables indoors would necessitate the doubling of the current power supply, and this would only free up 2% of crop land. These numbers don’t consider the energy required for climate control either, such as heating in the winter and cooling in the summer (Cox and Tassel 2010). Examining these inputs discredits the idea that vertical farming is an efficient use of space and resources. Agricultural solutions must be sustainable and scalable, neither of which apply to indoor growing.

Artificial trees in Singapore attract visitors to the island. (http://www.redicecreations.com/ul_img/20838supertreesC.jpg)

Artificial trees in Singapore attract visitors to the island. (http://www.redicecreations.com/ul_img/20838supertreesC.jpg)

The danger of promoting unrealistic growing methods is a resulting decrease in appreciation for large scale rural farming. The majority of the world’s food is generated this way, and incorporating traditional forms of agriculture into the urban environment is an alternative way to bring agriculture to the city without building high-input indoor systems. An analysis of Cleveland, Ohio found that using vacant lots, residential lawns, and hydroponic gardening on industrial and commercial rooftops can supply up to 100% of the city’s fresh produce need (Grewal and Grewal 2012). Additionally, outdoor urban agriculture can help reduce the urban heat island effect, mitigate storm water impacts, and lower the amount of energy that goes into food production (Ackerman et al. 2014), benefits that are lost when agriculture is moved indoors.

Plants grown in an indoor setting require an artificial source of light (http://2.bp.blogspot.com/-9QxCq9skL_A/U9Dc_lT2HsI/AAAAAAAACP0/ICf7Cw4TDI4/s1600/vericle-farming.png)

Plants grown in an indoor setting require an artificial source of light (http://2.bp.blogspot.com/-9QxCq9skL_A/U9Dc_lT2HsI/AAAAAAAACP0/ICf7Cw4TDI4/s1600/vericle-farming.png)

While plant-scrapers may not be a global solution, they do help increase awareness about sustainability issues. An indoor growing facility is intriguing and can help city dwellers reconnect with the natural world. The United Nations reported that 54% of the world’s population currently lives in cities, and this is expected to rise to 66% by the year 2050. Currently, the world contains 28 megacities with populations of over 10 million people; this number is expected to increase to 41 megacities by the year 2030, less than 6 years away. Inspiring urban dwellers to consider global food issues is therefore important, and urbanites may be inspired to start their own gardens upon seeing a beautiful plant-scraper. Plant-scrapers should not be viewed as the way of future farming, but seen as one way for a city to generate food with a limited amount of space.

Demanding forms of agriculture that can help feed the world in a sustainable manner is more important than demanding a flashy, futuristic form of farming that is less efficient. Incorporating plant-scrapers into cities should be done with the knowledge that these buildings contribute to the local food supply, but come at a cost and are not scalable on a global level. We must acknowledge the reality of our global state of agriculture and demand practical solutions; nature has mastered both form and function and we should strive to do the same.

UST Environmental Science students in national sustainability competition

The blog has been on hiatus for a while, partly because we’ve had so many exciting things going on.  One of our current projects involves investigating the feasibility of using hydroponic gardens to improve water quality in a local urban lake (Saint Paul’s Como Lake), turning a waste product (nutrient pollution) into a product of value (locally grown food).

The rationale is simple: many of our urban lakes suffer from excess phosphorus, which comes from our lawns and gardens, pet waste, and leaves.  Phosphorus is necessary for all life–it serves as the backbone of DNA, for example–but in lakes it fuels the growth of excess algae.  The decomposing algae can use up a lake’s dissolved oxygen, causing fish kills, and algae-covered lakes are less desirable for recreation.  Many different initiatives have focused on reducing phosphorus inputs to Como Lake, through increasing stormwater infiltration (through rain gardens or underground trenches) and from neighborhood leaf cleanup initiatives.  While these initiatives have reduced P inputs, the problem is that there is a huge amount of phosphorus stored in the lake sediments, which is the main contributor to lake water phosphorus.  To achieve any improvement in lake water quality, somehow we have to address this hidden source of phosphorus to the lake.

My students and I have conducted experiments with our 600-gallon aquaponics system for the last few years, in which vegetables grow hydroponically while removing nutrients from fish waste.  We wondered about using similar technology to clean urban lakes, and received a grant through EPA’s People, Prosperity, and the Planet Student Design Competition for Sustainability.

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Last summer Jessica Brown conducted the first phase of this work, funded by a Young Scholars grant through the UST Grants and Research Office.  Jessica’s study focused on measuring the maximum rates that different plant species could remove phosphorus from lake water, and on identifying limitation by other nutrients (like nitrogen and iron) that limit plant growth in lake water.  Her research showed that legumes (such as peas and beans) can partially compensate for low nitrogen in the lake water by “fixing” atmospheric nitrogen, but the plants require additional nutrition to thrive.  Currently my Environmental Problem Solving class is designing an experiment to find the best solution to this problem.  The class will also be exploring the effects of hydroponic gardens on lake water quality by building on the lake ecosystem model begun by research student Quinn Niederluecke.

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Results from Jessica Brown’s study measuring the amount of phosphorus that could be sequestered in different types of crops growing hydroponically in urban lake water.

In mid-April, a team of our students will travel to Washington D.C. to present our project at the National Sustainable Design Expo and compete for a Phase II award.  We’ll be posting updates on the project periodically throughout this semester.

The End of Growth? Perspectives from an Aquinas Honors seminar

“Questioning (economic) growth is deemed to be the act of lunatics, idealists, or revolutionaries. But question it we must. The idea of a non-growing economy may be an anathema to an economist. But the idea of a continually growing economy is an anathema to an ecologist.” – Tim Jackson, Prosperity Without Growth

‘Supertrees’, Singapore. Photo credit: Wikimedia Commons

‘Supertrees’, Singapore. Photo credit: Wikimedia Commons

Conventional economics is based on the assumption that the environment is merely a subset of the economy, resources can be infinitely substituted for one another, and human population growth and consumption can continue indefinitely. Growth is held out as the elixir for our social and economic ills such as unemployment, poverty, and the staggering government and private debt. In an age of rising energy costs, a changing climate, land use degradation, and an ever growing population, the importance of ecological consequences of economic growth are becoming increasingly obvious. This semester, Jim Vincent (UST Economics) and I lead an Aquinas Honors seminar to discuss relationships between economic growth and the environment. We asked our 12 students to write essays on an issue of their choice that integrated themes from Ecology and Economics.

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Masdar City: Oasis of Sustainability, or Just a Mirage?

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Can a city be truly sustainable?  In a 2012 paper, ecologist Robbie Burger argues that even Portland, Oregon, widely considered to be the “greenest” city in the United States, falls far short of true sustainability.  Despite the city’s farmers markets, bike trails, and public transportation, Portland’s per capita fossil fuel consumption was not much different than that of the average U.S. citizen.  Portland, like all cities, is intrinsically embedded within the larger, unsustainable, global economy.

Cities are like organisms: materials and energy come in and get processed, and waste products result.  In my Urban Ecosystem Ecology class, we’ve been digging in to studies of urban metabolism.  There are fundamental similarities across these cities, such as major CO2 fluxes generated from transportation and electricity production.

We came across an interesting, and very different, example in Masdar City, a planned sustainable city/research campus on the outskirts of Abu Dhabi.  While the United Arab Emirites is a leading oil producer, Masdar is powered by a massive 100 MW solar array, and built with passive technology to minimize the energy demand for cooling.  It’s also a car-free city, where futuristic driverless cars transport people between underground stations.  Labs in Masdar conduct research on renewable energy.  Masdar City has won accolades from various environmental groups, and is supported in part by the U.S. Department of Energy.

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Masdar City under construction in 2012. Source: Wikimedia Commons.

Is Masdar City truly a sustainable city?  Yes, the city’s carbon footprint is remarkably small (although not zero, as initially planned).  Sustainably harvested palmwood is used in construction, and greywater is planned to be used for crop irrigation.  On the other hand, currently the “city” only has around 4,000 residents (plans are for the population to grow to 50,000 in coming years).  There are no gas-burning cars in the city proper, but many workers commute from nearby Abu Dhabi.

What raised the biggest red flag for me, from the video we watched, was seeing the CEO of Masdar, Dr. Sultan Ahmed al Jaber, explain why Abu Dhabi is trying to become a leader in sustainable energy production, despite its oil riches.  He explains that the emirate loses money with every barrel of oil that it uses domestically rather than exporting.

If the ultimate goal of this “sustainable city” is for more Middle Eastern oil to be burned in the United States, that doesn’t bode well.  That’s like a city shutting down its local power plant, and instead importing electricity from a more distant plant, and claiming to have drastically cut its CO2 emissions.  It might look good on paper, but it accomplishes nothing.  Robbie Burger’s argument was that sustainability must be considered in a holistic sense–there is no validity in walling off a city (either figuratively, or, in the case of Masdar City, literally) and proclaiming it to be sustainable.  Climate change is a global problem, and externalizing pollution to achieve local-scale sustainability is little more than a marketing ploy.  On the other hand, if Masdar City’s model of government-owned, profit-driven sustainability research drives innovations that gain traction and become widely accepted, perhaps there are real benefits.

Aquaponics Update

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As winter continues its grip on Minnesota, a tropical river ecosystem is thriving inside the OWS greenhouse.  We started last spring with a small-scale experiment, asking how efficiently we could turn food waste into worms, worms into tilapia, and tilapia waste into basil.

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Last summer we started up a 600-gallon aquaponics system where we grew a crop of tomatoes, and now we’re growing kale and basil.  I also started a collaboration with Healing Haiti, an aid organization that runs a commercial-scale aquaponics system in a village near Port-au-Prince.

Students in my Urban Ecosystem Ecology class are currently constructing an ecosystem model using STELLA software, based on our data from the small experiments, the larger greenhouse system, and the giant system in Haiti.  Our goal is to create a management tool that will help managers run the Haiti system more efficiently, thereby increasing the capacity for food production in the poorest country in our hemisphere.

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We’re also kicking off a new experiment with the six smaller aquaponics systems, involving freshwater shrimp (Macrobrachium rosenbergii).  We’ll be growing shrimp and tilapia, separately and in combination, to measure overvielding–i.e., do we get extra animal production per unit of food added in the higher biodiversity treatments?

The shrimp have arrived and are settling in to their new homes.  Unfortunately, with the cold weather, our new tilapia have not been shipped from their home in south Florida.  Hopefully they’ll ship in a few weeks and we’ll get started.  Stay tuned for details.

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Scientists stepping out of the ivory tower

This week I read a pair of remarkable articles on scientists who have stood up against industry.

The first piece, in the Feb. 10 edition of The New Yorker, profiles UC-Berkeley toxicologist Tyrone Hayes and is decade-long battle against agrochemical giant Syngenta regarding the credibility of his research showing that trace amounts of the herbicide atrazine can cause hermaphrodism in frogs.  Recent documents reveal the extent to which the company deployed legal and communications teams to attempt to discredit Hayes. 

The second article, in the Feb. 7 edition of Science, profiles University of Maryland ecologist Margaret Palmer, whose research on stream restoration has led to her frequent appearances as an expert witness in court battles over mountaintop removal mining in West Virginia (and even an appearance on the Colbert Report!).  The article documents examples of cross-examinations that verge on personal attacks, yet the naturally-introverted Palmer has remained unflappable.

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The landscape of much of West Virginia has been altered through mountaintop removal, prompting University of Maryland ecologist Margaret Palmer to become engaged in legal battles. Photo: Wikimedia Commons

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On not seeing the forest for the trees (or the watershed for the lake)

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One lesson I try to get across to my students is the importance of thinking about environmental problems from a holistic perspective.  Otherwise, focusing only on one part of a problem can inadvertently worsen other problems (some interesting examples described in this article by Emily Bernhardt).

One problem that I think about a lot (as do many other Minnesotans) is the issue of nutrient pollution in lakes.  The classic lake management success story is Lake Washington, near the city of Seattle.  During the 1940’s and 1950’s, eleven sewage treatment plants were discharging nutrient-rich treated wastewater directly into the lake.  The fertilization of the lake resulted in massive blooms of blue-green algae, and led to fish kills.  Based on years of data collected by the limnologist Tommy Edmondson at the University of Washington, phosphorus was identified as the culprit, and a series of expensive engineering projects eventually re-routed the wastewater discharge directly into Puget Sound, bypassing the lake.  Over the ensuing decades, water quality improved, and the lake is now twice as clear as it was in 1950.

Something about this story has always bothered me, though.  Puget Sound has its own problems with nutrient pollution.  Shunting pollution further downstream is an awfully narrow definition of success.  Every ecosystem is embedded in a larger ecosystem.  Sustainability requires considering the whole, not just one of the parts.

I was reminded of the Lake Washington story by an article that my mother-in-law sent me recently, about Jordan Lake, a reservoir in my home state of North Carolina.  This reservoir is a popular recreation spot near Raleigh (I used to kayak there) and provides drinking water for more than a quarter of a million people.  And, like many lakes near urban areas, it has suffered from nutrient pollution and algal blooms.  To address this problem, the state has imposed strict limits on nutrient runoff throughout the lake’s watershed, a policy that some in the business community have argued is costly and ineffective.

The state is now shifting gears and trying a completely different approach by installing 36 solar-powered pumps throughout the reservoir to circulate water.  The idea is that by mixing water from different depths, algae will not have enough light to survive, despite the excess nutrients.  The proponent of this plan is a former toxicologist for the EPA, who now works for the company that makes these pumps (and is leasing them to the state for $1.4 million for the next two years).  As part of this plan, the state will ease regulations on nutrient runoff.

There’s plenty of politics at play here.  The GOP controls the state government now, and is happy to loosen environmental regulations that it considers to be expensive and ineffective.  State Senator Rick Gunn, who led the rewrite of the environmental program, claims that high nutrients alone are not a problem.

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After years of problems with excess nutrients leading to algal blooms, the state is trying a different approach by installing solar-powered pumps to mix the lake water–while easing restrictions on nutrient control. Image: Wikimedia Commons.

These pumps have been deployed in several other lakes around the country, with mixed results.  Will they work here?  Maybe.  I think it’s an interesting experiment.  But the part about easing nutrient restrictions–that gets back to the Lake Washington problem.  The thing about rivers is that water moves downstream.  Even if the pumps work perfectly and prevent algae blooms in Jordan Lake–and that’s a big “if”–these excess nutrients are going to flow into, and out of the reservoir, and on down the Cape Fear River, eventually reaching the coast where they undoubtedly will cause problems.

This is a case of treating the symptoms and ignoring the underlying problem.  Sometimes you need to pay attention to both–and that requires looking at the big picture.

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