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SSIR – Bangalore Lakes by Michel St. Pierre
On October 16th, Sherwood Institute board member Michel St. Pierre published an article titled “Sustainable Development in India” in the Stanford Social Innovation Review in which he discusses the work the Sherwood Institute’s work in Bangalore, and how the city has been affected by India’s quickly rising population. “Bangalore… is a metropolis of 5.4 million people that was once dotted with hundreds of lakes, which created a livable city providing food and water for residents, opportunities for livelihoods, habitat for rare and migratory birds, and a rich cultural heritage” Pierre describes. “With the city’s rapid development, and a lack of public action to protect the natural resources of the city, today less than a third of the lakes remain. There is pollution from human and industrial waste and land filling has occurred through illegal dumping and development.” Sherwood Institute’s project to restore the lakes of Bangalore encourages innovation, as a solution must integrate many aspects of the city’s infrastructure, ecological and social systems. “The solution includes efforts in a variety of areas: from garnering local political support and creating a Lake Development Advisory Commission, to working to affect policy in Bangalore and fundraising for early phase restoration efforts.” Pierre “believe[s] that the vision for the lake restoration is a key step toward a major quality of urban life enhancement in Bangalore… Hopefully, this initiative can provide a way forward for similar initiatives elsewhere in the country.”
This month, St. Pierre will be presenting with Sherwood Institute Associate Director John Leys at the Greenbuild International Conference and Expo in San Francisco on the topic. The talk will take place on November 15th from 1:30-2:30pm. Details here. (link to GB site session info)
Click here to read the full article.
Old Summer Palace: Example of Chinese Public Involvement in Environmental Issues
The Old Summer Palace is one of the “must sees” for both Chinese and international visitors to Beijing. Historically, the 860 acres, comprised of the Garden of Perfect Brightness, the Garden of Eternal Spring, and the Elegant Spring Garden has been known as the “Garden of Gardens” in Chinese for its once exquisite collections of stone palaces, landscaping, waterscaping and artwork. After the looting and burning of the site by British and French troops in 1860 during the Opium War however, the ruins of the Old Summer Palace still represent the shame of many Chinese feel from foreign imperialist forces in China’s modern history. The importance of the site is unquestionable, both for international visitors and for Chinese.
Thus, when Chinese environmental activist and visiting professor at Lanzhou University, Zhengchun Zhang posted an open letter was on the Internet in 2005, exposing park officials’ plans to line the gardens’ lake beds with plastic to prevent lakes’ water from being lost through infiltration into the underlying groundwater, a storm of public outrage erupted. Although the plan to seal the lakebed was made in the good interest of the preservation of the Old Summer Palace’s waterfront aesthetics, it was exposed that the plan, which had an estimated cost of 3.6 million US dollars, did not undergo any environmental impact assessment, an approval required by law before any construction begins.
The decision to line the beds of the lakes within the Old Summer Palace with plastic came from the park administration. Beijing is one of the thirstiest cities in the world, with a per capita water resource amount of only one-thirtieth the international average. Falling groundwater levels have also caused surface water to infiltrate more quickly into the ground so that for the lakes such as those in the Old Summer Palace, surface water levels also fall. Because rainwater is also scarce, replenishment of the lake took place artificially, putting extra burden on the city’s already-strained municipal water supply. With no action, the water has to be added into the lakes three times per year; with the planned liners, they only have to be artificially replenished once per year. Preventing loss of water from infiltration to the underlying groundwater would be able to maintain water levels for the flora and fauna dependent on the lakes.
However, opponents of the plan debated fiercely through both online and traditional media outlets. The plan was reminiscent of many other projects to line canals and riverbeds with cement, which began in the 1990’s in Beijing and contributed new ecological challenges. Hard-facing water bodies eliminates interaction between water and the underlying sediment, a crucial part of the ecosystem balance. It also changes the overall hydrology. In summer months, concrete –surfaced lakes heats faster than sediment and accelerates evaporation. The flows between water bodies could also be disrupted, and could change some areas into “dead water”, or even accelerate flow out of the site. Although the plan for the Old Summer Palace called for plastic liners, possible toxic effects of such liners on the ecosystem were not evaluated in any way. Others said that the surface water bodies within the park also constitute historical marsh areas which recharge the areas groundwater levels. Without evaluation, the effects of cutting off such a such of groundwater replenishment were unknown.
Because of the amount of attention the project garnered through online discussion forums and traditional media, the first-ever national level environmental public hearing was called by the National State Environmental Protection Agency (SEPA, now the Ministry of Environmental Protection). This was the first time that environmental governance was spurred through pressure from the general public rather than from regulatory officials, and thus, was a milestone in China’s environmental democratization.
As a result, Tsinghua University’s Environmental Impact Assessment (EIA) Office was called upon to carry out a public report on the site, which at the time of the public hearing, already neared completion. This report was assembled by a team of university experts and made the following recommendations:
1. The eastern portion of the site should not carry out further sealing using the plastic membrane, and that natural clay material should be used to reduce infiltration.
2. The plastic membrane installed at the mouth of Elegant Spring Garden should be removed and replaced with clay filling and the original sediment of the lake. The banks of the lake should not utilize any sealing membrane.
3. The areas of Eternal Spring Garden lake higher than 40.7 meters should immediately remove the sealant membrane and fill with clay. No sealant membrane should be used on the banks.
4. The installed sealant membrane in Fuhai Lake should be modified. Where gravel has been used as fill, the surface sand should be replaced with natural clay and all the original sediment should be replaced. Other than the area within 10 meters of the dock, the sealant membrane on the revetments of other areas should be removed to ensure adequate infiltration. Additionally, in order to satisfy the ecological needs of the Old Summer Palace park grounds, water usage plans must be made systematically, and the efforts must be made to ensure the quality of the water and prevent contamination
The assessment by Tsinghua University was accepted by SEPA. The report also acknowledged that while these recommendations would likely improve the water shortage situation in the lakes, the impact of the regional hydrology was likely to suffer, and because construction of the sealed lakebeds already neared completion at the time of the report, the true ecological costs of the project could not be assessed.
The expert team from Tsinghua University and general public participants in the hearing mentioned the use of reclaimed wastewater to replenish the lakes. However, like many other water-intensive industries that have been instructed to make use of the city’s reclaimed wastewater resources, it is possible that the limited distribution network and the quality of the reclaimed wastewater may make this difficult presently. In addition, other experts suggested that the sizing and depths of the lakes be adjusted to reflect Beijing’s current water scarcity situation.
Although there may not be one comprehensive answer to the challenges of preserving this historical site, the public hearing held by SEPA at the time fostered the government’s support of public debate on environmental issues. One source reports that in a random sampling of 100 articles returned from a Google search “The Old Summer Palace EIA”, 60 were classified as news articles from major media sources, and 15% were articles from personal blogs or webpages. BBS threads were also an important means of communication, with about half expressing “outrage”, one-sixth supporting the idea of water-tight membranes for conserving water in the lakes, and about 35% expressing neutrality. The second-most supported BBS message on one forum (after one expressing outrage at the membrane itself) was one that expressed dissatisfaction with the fact that the construction of the project was begun without any environmental impact assessment.
A report done by the Woodrow Wilson International Center for Scholars, found that EIAs in China currently do not sufficiently incorporate ecological issues. A personal conversation with a developer based in Beijing, also confirmed that of all the permits required for a new development, the environmental permits are the easiest to secure. The major problems were listed as follows:
Lack of baseline information about ecological subjects;
Inadequate skill sets among environmental assessment practitioners related to impact prediction, mitigation and restoration, and monitoring.
Post-impact monitoring is not strongly emphasized in training programs
Little value of the importance of public participation in assessments and methods to involve communities
Insufficient sharing of best practice models and international experiences among assessment practitioners.
The above are opportunities for improvement, but, the direction is positive. The same report states that a survey of practitioners of EIAs in China revealed that all showed genuine interest in learning how to better predict environmental impacts. In 2002, the Central Government also released a new version of the China Environmental Impact Assessment Law, which, in addition to requiring all renovation and construction projects carry out EIAs, also encourages greater public participation in the “social duty” of environmental protection. The case of the lakebed sealing at the Old Summer Palace Site, is an excellent and positive example of the future of public participation and EIA.
Water Efficiency Series: Part 2- Utilizing Graywater
Graywater, or “light graywater” is generally defined as water that has not been in contact with human waste and organics, water that has been used once in sinks, showers or washing machines. This differs from “dark” graywater, which includes water from kitchen sinks or dishwashers, and blackwater, which is wastewater from toilets.
It is estimated by the US EPA that the average household of four uses about 400 gallons of water per day. Approximately 70% of this is for indoor use and over 10% is usable graywater. As many states and countries are facing droughts more often, reusing graywater could prove to be a very beneficial strategy.
Graywater is most easily and commonly reused for irrigation purposes. The safest method is subsurface irrigation, where the water does not come in contact with humans and where amounts are generally not significant enough to infiltrate the drinking water supply. Whitewater (potable water that meets the EPA’s drinking water standards) should still be used for irrigation of food crops other than fruit and nut trees where the crop is far away from the ground. Subsurface irrigation ensures that the graywater will not pool on the surface or runoff, which could result in odors, mosquitoes, pollution, building damage and unsanitary conditions.
According to the U.S Geological Survey, about 1/3 of residential water use is used outside (mostly for landscape irrigation), which is about 7.8 billion gallons a day! (Source: U.S. EPA’s Water Efficiency Landscaping publication). This means there is a huge opportunity to recycle water for irrigation purposes.
Graywater systems for reuse generally consist of collection plumbing, treatment methods, disinfection and distribution components.
Dual plumbing is required in order to separate wastewater from graywater and blackwater sources. If graywater is used for subsurface irrigation, the system can be very simple, with just a three way manual valve installed that can cut off graywater to irrigation if an anticipated load is too heavily contaminated. Soil must also be tested prior to design to determine if a surge tank is needed to handle peak water loads. The surge tank is not a long term storage tank. Graywater should be treated or distributed immediately as the organic material in the water will cause it to become unusable and possibly harmful in as little as 24 hours.
For complex systems the next step is treatment. These scenarios include but are not limited to: graywater used for surface irrigation or indoor use, large collection sources, systems that store water and areas with stricter permitting regulations.
After a filtration pretreatment, treatment methods can include mulch basins, media filtration, filtration membranes, biological treatment and constructed wetlands. I highly recommend reading Sustainable Infrastructure: The Guide to Green Engineering and Design to learn more about each method as I could write an entire blog about each one!
After treatment, water should also be disinfected if it will be used indoors or aboveground. Water can be disinfected using ultraviolet irradiation or by adding chemicals such as chlorine, chlorine dioxide or iodine. Non-chemical methods are preferable, but also more expensive.
There are many ways to distribute graywater. In the simplest of systems, gravity carries water from the building to the lower-elevation landscape. Advanced systems generally require pumping in order to force water through treatment equipment. Water can be distributed through single or branch pipe systems directly to the landscape, to mulch basins, to small leachfields, through a perforated pipe to gravel filled trenches, to subsurface drip systems, or to subsoil infiltration galleys.
Graywater can be an excellent water resource; however, many factors contribute to ensuring a high-quality system. First of all, thorough planning and sound engineering are essential for a successful system. The soil conditions, climate, anticipated loads and end use are just a few of the many issues that must be analyzed during the design process.
After construction, the user must carefully maintain the system and be conscious of what is entering the system. Before doing research on graywater systems, I was very concerned about how soaps and detergents can be okay for plant life. I learned that although it is important to use environmentally-friendly products and be aware of what is going down the drain, generally the chemicals and salts introduced to plants and soils in small-scale graywater irrigation projects are usually too minimal to have any negative effects.
In fact, some of the articles I read stated that the nitrogen and phosphorous from soap and the potassium found in food actually nourishes plant life and recharges top soil. It is most important, however, to avoid soaps with sodium, chlorine, boron, borax, bleach and high levels of phosphates.
As policies allowing and promoting graywater use are beginning to increase, there are more and more government resources to read and learn all about graywater use. The EPA water recycling and reuse website, the Graywater Guidebook released by the State of California and Sustainable Infrastructure: The Guide to Green Engineering and Design are a few resources to start with. I hope graywater use will continue to expand and be more widely accepted as a water resource with the general public, as water recycling will help alleviate some of the stress on our current infrastructure. Water scarcity is an growing problem that will only increase in the years to come, we need to start implementing solutions now.
Beijing Golf Course Water Conservation Needs and Strategies
Since the opening of China’s first golf course in Guangdong Province in 1984, the country has seen a boom in the sport, which is a symbol to many Chinese of luxury, upper class lifestyle, and one of the pinnacles of western recreational status. In China, golf is something that only the very wealthy can afford, with club fees ranging from “cheap” at a couple thousand dollars per year to tens of thousands of dollars per year for the very exclusive courses, meaning that only approximately one in every 100,000 Chinese people could ever afford to play 18 holes in China. Despite the small number of potential Chinese golfers however, the symbol and status of golf in China has created a reasonable market for the development of golf courses.
Such development comes with significant environmental challenges. Most golf courses are constructed in the suburban areas of large metropolitan cities, which, especially in northern China are already strained for water resources. Golf course construction has several implications. Because the water required to maintain greens, tee boxes and fairways is significantly more than that of land covered by trees and bushes, strains are created on both groundwater and municipal water supply. The deforestation of areas to build 18-hole courses also increases soil evaporation, decreases infiltration, increases stormwater runoff and decreases the water-holding capacity of the soil. Also, since many suburban golf-courses are located on lands once used for agriculture, it is common practice to directly extract groundwater from agricultural wells already built on the land for irrigation purposes, which leads to the lowering of the groundwater table in areas which are already experiencing subsidence on a regional scale.
The municipal government of Beijing has of course, realized that this problem could be very severe. This year, in fact, Beijing experienced its driest winter to date, with 108 days straight with no precipitation. There have been several policies passed attempting to curtail water-intensive industries. In 2005, the Beijing Water Authority passed its first announcement on golf course water management, called the “Announcement on the strengthening of golf course water use management”. Within this document, it was specified that the 40 golf courses within Beijing’s 11 districts would have to pay doubled or tripled prices for water usage exceeded a set maximum. The announcement also stated that golf courses were required to utilized reclaimed wastewater for both waterscaping and irrigational purposes and that they should also maximize harvest of rainwater.
In 2006, another announcement was sent to all registered in Beijing, requiring golf courses to register usage of on-site wells, increase permeable areas (such as paths, parking lots, etc) on the site, maintain irrigation equipment, and for golf courses within the distribution network of reclaimed wastewater to utilize this as a source for irrigation, and flushing toilets.
In 2010, the opening of new water-consuming enterprises—including new ski slopes, golf courses, and bathhouses—in Beijing was banned.
While these policies were definitely a step in the right direction, several articles question their efficacy and the extent to which the policies are actually enforced. In March 2010, Probe International published a report which stated that “fewer than 7 percent of Beijing’s golf courses use reclaimed water for irrigation despite municipal guidelines that strongly suggest they do”. On February 11 of this year, the Economist published an article stating that according to aerial photographs, there are 170 confirmed golfing establishments in Beijing, including driving ranges. Previous estimates of the number of golf courses vary because some places avoid calling themselves “golf courses” in order to have more leniencies in management. The official Xinhua News Agency reports 38 golf courses as of 2010
Although there are definitely some questionable aspects of the efficacy of legislation and the commitment various players have in their implementation, there is no doubt that golf courses in Beijing must adopt water reuse and saving measures. There are three main strategies that are important in golf course water management.
The first is to increase the amount of reclaimed wastewater that is being used for irrigation and waterscaping. As of August 2010, only 4 of the 38 official golf courses were utilizing reclaimed wastewater for irrigation. Interestingly, in the same month, it was also reported in Chinese media that the demand for reclaimed wastewater in Beijing far exceeded its supply. In many developed countries, technology is good enough that up to 70% of all wastewater can be reused as reclaimed wastewater after treatment. In Beijing, only about 10% of wastewater is being reutilized, so the potential for reclaimed wastewater to be a major water resource in the future is very large. Because in some cases, wastewater treatment plant effluent may not meet standards for irrigation or waterscaping uses (especially if nutrient levels are high), golf courses may consider the use of constructed wetlands to raise the quality of the water. This strategy may even allow for golf courses outside the reach of the current reclaimed wastewater distribution network to carry out additional treatment of treatment plant effluent to raise the quality of the water independently.
The second strategy that will be important for golf courses in Beijing to adopt is drainage and rainwater harvest design. Because grass lawns experience greater runoff than forested areas, specific attention needs to be considered in the grading of the landscape with respect to maximizing infiltration into the underlying aquifers and in minimizing waste during irrigation. Expert engineers should be consulted for questions relating to soil type, infiltration speed, soil water capacity, and grading.
Lastly, the selection of drought-resistant plant species should also be considered in golf course design. Already in Beijing it is reported that drought resistant grass is already being used for fairways and roughs, which typically account for over 60% of the total area of the course.
Research is being done on golf industry development at the Turfgrass Institute of Beijing Forestry University.
Strategies for Sustainable Snow Management
I currently live by Lake Tahoe in Placer County, California. We have the highest annual snowfall of any county in the lower 48 US states. After living here this month, I don’t doubt it! According to one of the local ski resorts, Alpine Meadows, the snowstorms of November 2010 have produced record amounts of snow, 6 feet in 6 days!
Over the course of the storm I watched as enormous plows cleared the roads. Later huge snow-blowing vehicles would come widen the road. And lastly, after the storm, bulldozers cleared the built up banks and drifts to get the roads, almost, back to normal.
I started thinking about how unsustainable this method of snow removal is. Not only are there emissions associated with the operation of massive equipment, but also contamination of the snow from salt and sand, road-side litter, and automotive pollutants. Lastly, snow removal is hugely expensive! In Placer County 15-20% of the annual road maintenance budget is spent on snow and ice control. I decided to do some research into solutions that incorporate sustainable snow removal and possible reuse in areas that receive a large amount of snow precipitation.
The most inspirational methods came from the City of Sapporo, the capital of the northern-most Japanese island of Hokkaido. Sustainable urban development is at the core of Sapporo’s city planning, and as a city with approximately 20 feet of snow accumulation and a population of 1.9 million people, it is vital that snow removal be part of the city’s sustainable initiatives.
Sapporo minimizes its dependence on snow-related transportation using heated roadways, centralized and local snow disposal facilities, and snow melting systems. In addition to a large, underground snow-melting tank, Sapporo has five Snow Flowing Gutters, which use river water and reclaimed water to move and melt snow.
This gutter system particularly intrigued me. Basically, there are grates at the sidewalk’s edge. Citizens then dispose of the snow in front of their residence and businesses into the gutters. The flowing water carries the snow to a treatment plant or to a snow-melting tank. If reclaimed wastewater is used, the temperature of the flowing water is generally about 50 degrees Fahrenheit, which melts the snow. This system eliminates the use of large mechanical vehicles and the emissions and cost associated with them, reduces the need to chemically melt snow, and empowers the city’s inhabitants to help with snow removal. However, the system is still centralized and the reclaimed water and melted snow are still being carried through pipes off-site.
I wonder how this system could be further developed. Instead of just transporting and disposing of the snow in an innovative way, what if the water from the melted snow could be reused or treated entirely on site in order to reduce stormwater runoff and recharge the groundwater? Designers could use low-impact design stormwater or rainwater harvesting principles to the melted snow.
This way snow removal would become part of a circular water system. In areas with considerable snow accumulation, geothermal heat pumps or energy from renewable sources such as photovoltaic panels or a small-scale wind turbine could heat sidewalks or roadways. In areas with only moderate snowfall this step could be eliminated. Remaining snow would be shoveled into grates, bringing it underground where it could mix with reclaimed “waste” water to aid in melting the snow. Finally, all of the water from the premises (wastewater, graywater, stormwater AND snow-melt) could be handled using any variety of sustainable design strategies. In this context, I particularly like a system similar to that designed by Sherwood Engineers and CMG Landscape Architecture for Old Mint Plaza, where the combined water could infiltrate to the groundwater table.
Over the last two weeks of researching the concept of sustainable snow removal, I have come across many concepts that are in use, and I’ve started to think of new ways to manipulate these systems. I am truly excited about the idea and I would love to hear about any methods that readers have heard of or thought about!
Agricultural management in the Tai Lake region
Following the conversation from the eutrophication of Lake Tai (Taihu), probably the most publicized Chinese eutrophication event in Western media, many will probably want to know more about the sources of the excess nutirents leading to massive algal blooms and deteriorating water quality. In February, the New York Times reported that previous information on the extent of the deteriorating surface water quality in China severely underestimated the scale and influence of agricultural runoff, focusing mostly on point sources such as industrial effluent. Ma Jun, director of the Institute of Public and Environmental Affairs, a nonprofit research group in Beijing, rightly pointed out in the article that pollution emissions stemming from millions of rural farmers will prove an even bigger challenge than slapping fines on factories and industrial sources. But, China’s Ministry of Environmental Protection is now beginning to realize that the agricultural contribution to poor surface water quality is just as prominent as the industrial contribution. Here I will give a brief overview of the issues at hand, from the perspective of nitrogen as an excess nutrient pollutant stemming from agricultural sources. In a previous post, we identified the main source of total nitrogen content in Lake Tai as having an agricultural origin.
In contrast to Europe and the United States, which could both be argued to have undergone agricultural intensification over a period of centuries, in China, the shift from traditional, complex, labor-intensive farming systems based on nutrient recycling happened over about four decades. Now, China’s agricultural system as a whole is heavily dependent on introduced inorganic nitorgen fertilizers and is utilizing less and less organic and green manures to replenish nutrients that are removed from agricultural soils when crops are harvested. The agricultural scheme utilized in the Tai Lake region is one of the two most intensive double cropping systems in China: summer waterlogged rice followed by winter upland wheat.
Generally, inorganic nitrogen, which, in the case of China, is usually introduced to fields in the form of urea-based fertilizers, is quickly converted into ammonium (NH4+) and later into nitrate (NO3-) by microorganisms in the soil according to the normal function of the nitrogen cycle. A portion of the nitrogen is also lost by NH3 volatization to the atmosphere, which contributes to air pollution and acid rain. Most plants, including rice and wheat. more readily take up the nitrate form of nitrogen than they do the ammonuium form. However, due to the negative repelling charge of nitrite with the surrounding soil (especially if the soil’s content is high in clay), the nitrate form is also highly mobile in soil and is easily carried by percolating water into surface water or groundwater. Ammonium, on the other hand, sorbs to clay and organic matter, and although is less readily absorbed by plants, is held in soil for a prolonged period of time if not further converted to the nitrate form. Organic nitrogen supplements, including proteins or amino acids found in animal waste, are a slow release source of nitrogen for crops, as organic nitrogen must first be converted into its inorganic forms in order to be taken up by plants.
Nitrogen that is quickly converted from urea fertizlier into nitrate is lost by leaching through soil into water. Studies on the intensive wheat/rice double crop cycle followed in the Taihu region show that alternating wheat and waterlogged rice leads to an accumulation of nitrate after the wheat season. However, flooded rice fields in the following season results in much of the nitrate being lost by leaching. (Ju et al 2009) Farmers in the Tai Lake region also tend to use more fertilizer during the wheat season than wheat farmers in northern China, but result in lower grain yields. A possible explanation is that Tai Lake region farmers try to use increased amounts of fertilizer to compensate for poorer wheat cultivation conditions.
Much of the problem of nitrogen leaching lies in agricultural practices . One- poor wheat-growing conditions in the Lake Tai region lead farmers to overuse fertilizers (with little to no effectiveness achieved in crop gain) during the wheat season, and two- the traditional use of flooded rice paddies promotes nitrogen leaching. We can see here that one aspect of the problem is psychological: with farmers holding to the belief that increasing inorganic fertilizer use will lead to increased crop yields. The other aspect is technical.
The System of Rice Intensification (SRI), developed in 1983 by Henri de Laulanie, a French agricultural practioner living in Madagascar, is one method that has been utilized worldwide to increase rice yields with fewer water and fertilizer inputs. One key aspect to SRI is that, unlike traditional rice cultivation methods, rice plants are not kept under waterlogged conditions, but instead, rotated between wet and dry conditions. Alternating between wet and dry causes cracking of the earth, promoting aeration of the soil, increased root growth, and slower leaching of nitrogen from the topsoil. The wider root systems of each individual rice plant is then able to take up more of the applied nutrients (nitrogen) from the soil, resulting in healthier plants with more tillers, and better yields. In Sichuan Province, farmers have achieved 40% greater yields using SRI, with less water and nutrient inputs.
However, as China has a rice cultivation history that spans thousands of years, urging farmers to change their flooding methods will continue to be a difficult task. This, coupled with the relatively recent introduction of inorganic fertilizers and their overuse will probably be the biggest challenge in reducing the contribution of agricultural sources of nitrogen to water deterioration in the Tai Lake region. Experts (Want et al 2006, Richter et al 2000) have recognized the need to the economic “internalization of environmental externality”, calling for measures such as the removal of government subsidies on agricultural fertilizers (reducing over application of nitrogen to fields) and improvements on water pricing and water rights legislation (reducing unneeded water usage by adjusting prices to reflect the costs of using the resource and reflecting the needs of water quality improvements).
Richter, et al. 2000. “The N-Cycle as determined by intensive agriculture– examples from central Europe and China” Nutrient Cycling in Agroecosystems.
Wang, et al. 2006. “Toward Integrated Environmental Management for Challenges in Water Environmental Protection of Lake Taihu Basin in China”. Environmental Management.
Oli otya from Ddegeya, Uganda!
The following post was written by Sherwood’s Michael Thornton, currently based in Ddegeya, Uganda.
For the next three weeks I’ll be reporting from here as I continue my work with the MIT chapter of Engineers Without Borders. We’re here in Ddegeya in the second year of a five year project to enhance the quality of life of this rural village of about 1,000 through enhancements to the village’s water and power infrastructure.
The MIT EWB chapter (check out their blog HERE) has done an amazing job assessing the base conditions, researching solutions, gathering stakeholder input and planning designs. The purpose of this trip is to implementation; in this case meaning installing a 1.4 kW solar system, testing and fixing boreholes and testing homemade sand filters and the flocculation capacity of a local seed from the meringe tree. This is my second trip to Ddegeya; last summer with the Sherwood Institute’s backing I spent three weeks here performing a pre-site site analysis review of the village, its resources and environment. For those interested, I’d be happy to send around the report from this visit. This trip finds me with a team of six members of the MIT EWB chapter as their trip mentor; basically an in-field professional responsible for overseeing all works.
In a later post I’ll go into more detail about the work we are doing. First, some background: Ddegeya is a rural village in south central Uganda, in the Masaka province. As you can see from the photos it is minimally developed and has a warm, dry climate. Uganda is one of the poorest nations in the world; its total GDP is equal to approximately 2-3 quarters of Apple’s revenue. Located a few miles from the equator, its seasonality is dominated by wet and dry cycles; its elevation (average 1206 meters in Kampala) keeps it relatively cool despite its equatorial location. Despite its poverty, it’s also a beautiful country with amazing people and a relatively stale government and rapidly developing infrastructure. Helping development here is helping the whole of Africa.
I am staying at, and much of our work is centered around, the Engeye health clinic a level two health center that is unable to offer many basic services due to lack of refrigeration and steady clean water. Part of EWB MIT’s goal is to solve these issues.
Presently there is no legal electricity in the village (one or two stores have tapped a transmission line for soda boxes) and water comes from a single shallow borehole and pond, seen below. The water from the borehole (fixed during my summer visit last year) is relatively clean, though insecure at only 20’ depth. The water from the pond is filthy and a regular disease vector, as water is in much of Uganda. The community sometimes boils water; sometimes does not. In addition to suffering from water born illnesses, many members of the community must walk miles to the borehole; taking valuable time and energy from their days and practically limiting the amount of water available to each family. Daily per capita water consumption is somewhere around 15 liters. Finding and developing more distributed, cleaner sources is of primary importance to the development of Ddegeya.
In the next post I’ll explore Uganda’s overall water / power situation and in the final post will provide more detail about the works we’ll have hopefully completed and the outlook moving forward. So stay tuned, and please post any questions you may have and I’ll do my best to answer!
A Closer Look at Water Issues in Bangalore
A study taken by the Centre for Symbiosis of Technology, Environment, and Management (STEP) approximated that 40% of the population of Bangalore is dependent on groundwater. There are around 125,000 private bore wells in the city. Because the extraction of groundwater is highly unregulated, the water tables have been rapidly depleting. According to R. Vasudevan, a chief engineer of the Bangalore Water Supply and Sewerage Board (BWSSB), the water levels have dropped 300 feet below ground level. The BWSSB extracts the majority of the water they distribute from the Cauvery River. This river is located almost 100 km away from the city and at an altitude of about 1,500 feet below that of the city. Because of this, approximately 75% of the total BWSSB revenue is spent on electricity charges. Another huge problem exists – almost 30% of the water extracted is lost to corroded and broken piping systems. The piping system in the city is over 50 years old. Many of the pipes are in horrible condition, producing many leaks. Unfortunately, the BWSSB has only made temporary fixes to repair the decaying pipes rather than to replace them entirely.
With such water shortages looming over the city, it is essential for changes in the water policy of the city to take effect. The BWSSB has just mandated rainwater harvesting last year as an amendment to the Bangalore Water Supply and Sewerage Act of 1964. The amendment states that all buildings with a total rooftop area of 2400 square feet or greater must install a rainwater harvesting system; all proposals for buildings with a total rooftop area of 1200 square feet or greater must include plans for a rainwater harvesting system. In order to see how effective rainwater harvesting can be, I have prepared a basic water balance of the city. The following values necessary for a balance were found. Some of the metrics were determined by simple calculations.
|Area of the City||
|Amount of Average Rainfall||
|TOTAL Amount of Rainfall in the City, Annual||
Water Demand Data:
Per Capita Water Demand*
|Population of the City||
|Water Demand for Domestic Use, Annually||
|Daily Water Demand for Other Uses**||
|Water Demand for Other Uses, Annually||
|TOTAL Water Demand, Annually||
*Please Note: This value is standard set by the Central Public Health and Environmental Organization. However, this is an overestimate of the per capita water use daily. Studies show that many people use only around 100 L of water per day.
**Please Note: This value encompasses the demand for commercial establishments, industrial users, institutional users, grounds (municipal and industry), fountains, and unaccounted for water (leakages). This data was gathered from surveys and interviews. The values were obtained from the Resource Optimization Initiative:
Eckelman, M. J., Shenoy. M., Ramaswamy, R., Chertow, M. 2010. Applying industrial ecology tools to increase understanding of demand-side water management in Bangalore, India. (unpublished manuscript).
If we look at the total amount of rainfall on the city and the total water demand, we see that the total rainfall is only slightly greater than the total water demand. We must take several things into account. First of all, it is not possible to capture 100% of the total rainfall. If we approximate that 70% of the total rainfall can be effectively captured to recharge aquifers, lakes, and bore wells, then the total water demand exceeds the amount of rainfall captured. This shows the severity of the water shortages in Bangalore. The numbers are too close to each other for comfort!
In order to alleviate the water scarcity issues, a greater campaign to install rainwater harvesting units should be invested in. People should be made aware of the advantages that rainwater harvesting can have. In addition, the BWSSB should work to expand their water reuse programs. Currently less than 1% of water is recycled for reuse. More sewage treatment plants should be installed to increase this percentage. There are many ways to solve this water crisis. Small steps can yield large results. Installing a rainwater harvesting system can be as cheap as 400 Indian Rupees (Approximately $8.50). The installation of such units will help both the people and the environment. The citizens of Bangalore can reap the benefits of sustainable water management while the environment can enjoy its water sources being replenished.
Bangalore Lakes in Grave Need of Help!
The last stop in my trip to India was Bangalore. Bangalore is the third largest city in India. Bangalore is known as the Silicon Valley of India, due to the rampant IT industry there. It is one of the most prominent cultural and economic hubs in India. Bangalore is truly a beautiful city. However, it is notorious for three things: traffic, frequent power outages, and severe water scarcity.
Let’s talk water – Almost all of the city’s water supply comes from the Cauvery and the Arkavathy Rivers. The Bangalore Water Supply and Sewerage Board (BWSSB) supplies approximately 900 million liters of water daily. However, the demand of water exceeds 1.2 billion liters. Many people once relied on the lakes to suffice their water needs. Most of the lakes of Bangalore are man-made, constructed for the purposes of drinking water, irrigation and fishing. Currently, the lakes in Bangalore suffer heavy amounts of pollution. The Greater Bangalore region once had 400 lakes. Now there are only around 93.
One lake that has suffered greatly from pollution is the Bellandur Lake. The Bellandur Lake is located in East Bangalore and spans an area of 960 acres. The Lake was once used a main source of water for the people of Bangalore. Water was used for irrigation, fishing, and for household matters, including drinking, washing, and cleaning. Until the 1970s, people in 18 different villages depended on the Bellandur Lake for their everyday needs. The lake has been greatly affected by the rapid urbanization that has been occurring in Bangalore. It has been negatively impacted by domestic and industrial pollution, the destruction of wetlands and the changes in the land usage surrounding the lake. Unplanned urbanization along with unchecked industrial, domestic, and commercial development caused the lake started to suffer greatly.
Currently, a large portion of the lake is covered in weeds and fields. The water in the lake is greatly polluted. There is no aquatic life within the lake. The stench emanating from the lake is beyond foul. At the outlet of the lake, heavy foam from an excess of industrial effluent can be seen.
The Bellandur Lake is connected to the Agara Lake through a stormwater drain. Bangalore consists of a series of interconnected lakes. The Agara and Madivalla connect to the Bellandur Lake. The outlet of the Bellandur connects to the Varthur. The lakes are connected by an extensive stormwater drainage system. The system once carried water, however, now it carries sewage. The Bellandur Lake is located in one of the three main valleys of Bangalore, known as the Koramangala and Challagatha Valley. Due to its location, the lake has been used to direct a large portion of Bangalore’s sewage. Currently, the BWSSB has set up three sewage treatment plants with a total capacity of 248 MLD. However, only 110 MLD of the total capacity is actually utilized. According to the BWSSB, by 2021, the volume of sewage produced by the city will be 359 MLD; by 2036, the volume will be 416 MLD. Already, urbanization and the flux of sewage into the lake have led to eutrophication. An increase in the volume of sewage will only lead to the lake’s further demise.
A major problem exists within the stormwater drains. There is so much pollution within these drains. Untreated domestic waste and industrial effluents are dumped straight into them. The pollution in the drains is directly transferred into the lakes. The pictures below show the pollution accumulating within these drains.
The lakes were once able to serve as natural wetlands, treating the wastewater that flowed into them from the stormwater drains. However, the amount of pollution in these drains exceeds the remediation capabilities of the lakes. The main problem exists in the lack of a strictly enforced waste disposal policy. Punishments should be given to those who are polluting the stormwater drains and the lakes. The citizens of Bangalore should be made aware of the amount of pollution entering the drains and also educated on proper waste disposal techniques, including recycling. Industries polluting the lakes should be fined heavily. Also, the BWSSB should work to increase the capabilities of their treatment plants.
There are various government bodies that are responsible for the Bellandur Lake, including: the Bruhat Bangalore Mahanagara Palike (BBMP), the BWSSB, the Minor Irrigations Department (MID), and the Lake Development Authority (LDA). The lake is located in the jurisdiction of the BBMP. The BBMP is the civic corporation that governs Bangalore. It is responsible for the maintenance of the storm water drains that lead into the lake. The BWSSB is responsible for properly regulating the sewage that enters the lake. The MID has ownership of the lake. The LDA is entrusted with maintaining and preserving the lakes in Bangalore. These organizations should work together to help preserve the lakes and stormwater drains.
There have been many pleas and enquiries to the government of the Bangalore to help remediate this situation. However, no substantial progress has been made. A strong commitment to restoring the Bellandur Lake and cleaning the stormwater drains must be taken.
All About the Three Gorges Dam
Reports of recent flooding in southern China have claimed the torrential rains to be the most severe in scope and damage since 1998. As of July 28th, an estimated 2.9 million people have been relocated, and economic damages have climbed to $3.354 billion. In addition to reports of on the natural catastrophe however, the China Daily, China Post, and Reuters have also observed that the Three Gorges Dam is facing its biggest challenge to date: withstanding and ameliorating the flood waters in the region. Officials are currently expressing concern that a number of dikes in the middle and lower reaches of the Yangze River are susceptible to damage from the accumulating water pressure. Three Gorges Dam engineers have opened three sluice gates to “discharge some 32,000 cubic meters of water per second and another sluice gate to release floating objects.”
The Three Gorges Dam was originally proposed for construction in 1919 by Sun Yatsen as a major source of hydroelectric power on the Yangtze River. Nearly 90 years later, in 2008, the dam was completed, setting world records as the largest electricity-generating plant of any kind. In addition to this massive engineering feat however, has come much controversy. In 2007, the New York Times reported that the project set records not only as the largest power plant in the world, it is also the largest dam, the largest consumer of dirt, stone, concrete and steel ever and has even caused the one history’s largest human resettlement programs. With the official announcement to construct the dam in 1992, came an onslaught of “unusually visible domestic opposition”. Concerns ranged from the fully scientific to the social problems that the construction of such a large structure would create.
Below I have provided a brief summary of some of the concerns people have raised against the dam: (in no particular order)
1. Accumulation of concentrated regional water pollution from surrounding areas
The Three Gorges Dam serves as a giant reservoir that stores water flowing from water basins in southern China, which are infamous for being heavily polluted with municipal and industrial waste, in addition to huge amounts of agricultural fertilizers. In 2001, the People’s Daily reported on the measures being taken to improve waste management strageties by the Central Government in the dam areas and upper reaches of the Yangtze. However, in 2004, the same newspaper released another report stating that many implementations had still not taken effect, including the closing of many small industrial enterprises that grossly surpass wastewater effluent standards, such as the paper and leather industries. The report stated that of 242 large-scale enterprises in the area, 227 also failed to meet standards.
2. Ecological disruption for hundreds of native species
Damming the Yangtze River inevitably causes disruption for the hundreds of species that are native to the area, including the endangered Baiji River Dolphin whose only native habitat is the Yangtze River. Because of the dam, fish species are unable to reach their upstream spawning habitats, affecting their natural biological cycles. Other affected species include the Chinese Sturgeon, Chinese Tiger, Chinese Alligator, Siberian Crane, and the Giant Panda. Chinese law currently protects a total of forty-seven rare or endangered species in the Three Gorges Dam area.
3. Dislocation of millions of local residents and loss of cultural artifacts
A result of the flooding of 632 square kilometers of land (bringing the total surface area of the dam to 1,045 square kilometers), 1.3 million local residents had to be relocated to other areas. There have been many reports on the psychological, emotional, and economic effects of displaced residents because of the Three Gorges Dam construction. As the water level of the dam rose over 600 feet, entire villages, towns, and even cities were left completely underwater. Although the central government provided allocations for the involuntarily displaced residents, many had trouble in the transition from rural to urban life, many lost their livelihoods with their farmlands, and many suffered from psychological trauma as their ancestral homes of generations were lost. In many cases, fertile farmlands were swallowed up by the rising waters, and reapportioned land distributed to local farmers was by far inferior and difficult to cultivate than the original land. An estimated 1,300 archaeological sites are also reported to have been lost in the flooded area.
The Yangtze River (undammed) carries about 680 million tons of silt to the East China Sea every year, making it one of the most heavily silted rivers in the world. It is estimated that each year 0.5 billion tons of silt will be trapped behind the dam, decreasing the effectiveness of the dam to prevent flood control and increasing the height of riverbeds, and the possibility of secondary pollution from the release of harmful chemicals that may be carried with river silt.
5. Increased landslides and earthquakes
From the increased weight over the flooded area from the dammed water and accumulated silt.
6. The making of an obvious terrorist target
All these negative aspects and concerns over the dam however have not made it a complete failure though. The dam, the largest clean-energy power plant in the world, is a symbol and a realization of China’s commitment to reducing its dependence on coal. A shift from coal reliance will not only benefit China’s environment, it will also improve air quality and reduce acid rain in neighboring Japan and Korea. As China is the world’s largest producer of greenhouse gasses, and is expecting to have even greater energy needs as it continues to develop its economy, “going green” for fuel requirements is perhaps enough to outweigh the negative consequences of the dam.
In addition, the Three Gorges Dam has a positive effect on the navigation of the Yangtze River. Trade along the river has been reported to account for 80 percent of China’s inland shipping. Elevated water levels not only make it possible for larger ships to safely travel up and downstream, the dam also lessens the phenomenon of whirlpools that influence smaller local shipping companies. One local is quoted, saying: “The whirlpools were big back then. If your boat got caught in one, it would spin you around. Now the river’s easy to navigate. Honestly, a 15-year-old kid could steer a boat up it, no problem. There are no big waves anymore.”
The final major point that proponents of the Three Gorges Dam cite is that it will be able to ameliorate the effects of flooding of the area surrounding the Yangtze River. Beginning in the Han Dynasty, records show that in 2,300 years, there have been over 214 major floods in the area, averaging one every ten years. Almost like clockwork, the floods of 2010 are being called the worst since 1998, but now the difference is the presence of the largest dam ever built by man. The Three Gorges Dam has been estimated to be able to protect 15 million people and 1.5 acres of farmland. During flooding seasons, the water in the dam is regulated to a lower level to help receive floodwater from the surrounding areas. During dry season, the dam can also help mitigate the effects of drought upstream. Facing the current flood conditions of southern China, authorities are regulating the water levels in the dam to lessen the impact of the flood downstream.
Some relevant articles debating the strengths and weaknesses of the Three Gorges Dam include:
- Burton, Sandra. “Taming the river wild.” Time 19 Dec 1994.
- “Editorials: ASIA NEEDS DAMS: And yes-there are ways to minimize ecological damage” Asiaweek 15 July 1996.
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