The project page also has more information about the project’s background and ways that you can get involved to help.

6 Main Task Areas for the environment are identified in the analysis. In order, they are:

1. Water Pollution Prevention and Treatment
2. Air Pollution Prevention and Treatment
3. Solid Waste Treatment and Disposal
4. Noise and Vibration Control
5. Environmental Monitoring
6. Environmental Services Industry

You can download both the original Chinese article and my (unofficial) English translation of the document below.

Click here to download original Chinese version (pdf)

Click here to download English translation (pdf)

Lake Dian, in Yunnan Province suffers from eutrophication and is one of the main lakes designated for remediation by the 12th Five Year Plan

The exhibits and conferences were free and open to the public and received media attention

This year, being the first year of the 12th FYP, the exhibition dedicated one full floor to summarize the progress made during the 11th FYP (2006-2010) through text, photos, models, and technology demostration, and to set goals for the 12th FYP (2011-2015). This year’s CIEPEC was hosted at the China International Exhibition Center, with over 30,000 square meters of exhibition space, organized into six exhibition halls, two of which were dedicated to stalls for international companies. In total, over 500 domestic and international companies were represented.  International exhibition areas were organized by Italy, France, the US, Germany, Japan, Korea, Canada, Holland, Beligum and Israel.

Exhibits addressed the following themes: Pollution control technologies, environmental monitoring and analysis, clean production and resource utilization, ecological remediation and protection, environmentally-friendly products and technologies, and the environmental service sector. Though more emphasis is being placed on the development of the environmental services sector in the 12th FYP, these firms represented a minority of the exhibits, indicating opportunity for international firms to transfer techniques to the Chinese market. The majority of exhibits focused on wastewater treatment techniques and environmental monitoring instruments.

An exhibit at the 12th China International Environmental Protection Exhibition and Conference

The conference proceedings handbook also contained a document entitled “Opinions about the development of the environmental protection industry during the 12^th Five-Year Plan period”, which features expert analysis of China’s Environmental Protection Industry in the context of development as outlined by the 12th FYP. There is currently no English version available for this document, but I will shortly be posting my translation of the document for reference.

The 12th Five Year Plan was discussed at the Fourth Session of the Eleventh National People’s Congress. Source: Chinanews.com

The first FYP was made for the period 1953-1957, so 2011 is the first year in the 12^th cycle of FYPs. In the previous few months, there was much discussion on the implementation success of the 11^th FYP, which will influence the content and implementation techniques for the 12^th FYP. Since this blog address environmental issues, I will try to speak about the FYPs’ implementation as they relate to China’s environment.

The implementation of the last year of the 11^th FYP (2006-2010), was discussed in depth on March 5, 2011 at the Fourth Session of the Eleventh National People’s Congress and a report (available in English) was prepared by the National Development and Reform Commission (NDRC). The summary included six points that were reported on:

1. Steady and rapid economic growth was maintained
2. The agricultural foundation was consolidated
3. Economic restructuring was carried out vigorously
4. Significant progress was made in energy conservation and environmental protection and in responding to climate change.
5. Reform and opening up were further intensified.
6. Efforts to ensure and improve the people s wellbeing were comprehensively strengthened.

Of these six, three are particularly relevant to the environment. The “agricultural foundation” that was consolidated in the second point refers to the three issues of rural areas, agricultural production, and farmers’ livelihoods. Water conservation is a big issue in agriculture. Currently, China not only needs to worry about food production for a rapidly growing urban population, but it also has to think about water conservation practices that will make food production more sustainable with the highest possible efficiency. In 2010, according to the NDRC report, the Central Government successfully formulated and carried out policies to intensify the construction of small and medium-sized water conservancy facilities. In addition, because public works in rural areas is generally also lagging behind urban areas, the living conditions of the rural population was also a big issue in 2010. The NDRC reported stated that in 2010 safe drinking water was provided to an additional 61.9 million rural residents than in 2009.

Volunteers test water quality in a rural area. In 2010, safe drinking water was provided to an additional 61.9 million rural residents than in 2009.

The second point that is of interest is economic restructuring. This point relates to the industrial and infrastructure plans that support the economic growth policies included in the first point. Low-efficiency “backward” production facilities were targeted for shut-down, including low capacity thermal power plants, steel mills, iron foundries, cement plants, plate glass plants, and paper mills. Shutting down small industries will allow the central government to better regulate contaminant emissions from industry, and to ensure that growth is happening in the most efficient way possible. In addition, this section also reported on massive infrastructural work that China accomplished during this period.

Nationwide, 4,986 kilometers of railway lines were put into operation, raising the total to 91,000; 120,000 kilometers of highways were opened to traffic, raising the total to 3.98 million; 500 kilometers of high-grade inland waterways were opened to navigation, raising the total to 10,000; 125 deepwater seaport berths were put into service, raising the total to 1,774; and 9 new civilian airports were put into service, raising the total to 175. Some 1.66 million kilometers of optical cables were installed, raising the total to 9.95 million kilometers; and 49.24 million broadband Internet access ports were opened up, raising the total to 188 million. We intensified the construction of key energy projects, energy bases, and storage and transportation facilities. Eleven out of 13 large coalmining bases have already reached a production capacity of 100 million tons.

To support economic restructuring, 4,986 kilometers of railway lines were put into operation in China during the 11th FYP. Some of these lines cut through environmentally sensitive areas. Photo source: Xinhua News Agency

Lastly, the point on environmental protection and energy conservation stated that all targets for energy targets and emissions reductions were met. These included installation of high-efficiency air conditioning units, and promotion of energy-efficient vehicles, and energy-saving light bulbs. The reported stated that through the implementation of 10 major national energy conservation projects, the energy equivalent of 33.1 million tons of standard coal was saved. Resource reuse was demonstrated through mineral recovery bases in urban areas. In 2010, 76.9% of urban sewage was treated, an increase of 1.6 percentage points from the previous year, and 72.5% of urban household waste was safely handled, an increase of 1.2 percentage points from 2009. Energy consumption, chemical oxygen demand, and sulfur dioxide emissions all met or exceeded the goals set by the 11^th FYP during the period from 2006-2010. Several specific remediation and reforestation projects were also mentioned, including the grassland remediation, virgin forest protection projects, and remediation of long-time problem areas, such as Dianchi Lake, and Tai Lake. According to the report, implementation had positive results. Lastly in this point, climate change was mentioned. The central government effectively implemented China’s National Climate Change Program. Successes in international exchanges and cooperation for improvement in low-carbon technology was emphasized.

After summarizing the achievements of the 11^th FYP and the work accomplished in 2010, there are six problems listed which are designated as “serious conflicts and problems facing domestic development”. The first problem listed is the issues relating to agriculture and rural development. Insufficient farmland and freshwater scarcity, poor water conservancy infrastructure, uncertainties over climate change, and generally low levels of agricultural science and technology will continue to be major constraints to agriculture and rural development that will have to be addressed. Another point within the six problems mentioned is that resource and environmental constraints have intensified. Energy usage and resource consumption is increasing too quickly and the level of major contaminant emission is too high. Energy-intensive and high-pollution industries are continuing to grow too quickly.

Small cement production facilities contribute to contaminant emissions and thus have been designated for shut-down by the Five Year Plans.

From the NDRC document, it is evident that there are possibly a few areas where expertise in sustainable design and green infrastructure will be very important. Civil engineering can be used in overall masterplanning to improve local hydrology in agricultural areas and water quality and supply in urban and rural areas. Energy conservation can be accomplished through applying guidelines such as those suggested by LEED in new buildings and communities. The transfer of these techniques that are more common in the United States and other developed countries to the Chinese environment is an area with an enormous amount of potential to make vast improvements.

Old gate of Tsinghua University, Beijing China, established in 1911

School of Environment, Tsinghua University

Persistent Organic Pollutants (POPs) are chemical contaminants which exhibit persistent, bioaccumulative, and toxic properties in the environment. They also have long distance transport potential and therefore have been found to exist in remote areas, such as the Arctic, where they accumulate in the fat, blood and inner organs of animals such as polar bears. The Stockholm Convention on POPs was signed in 2001 and put into effect in 2004, as an international accord to reduce and eliminate the use and production of designated POPs. The original convention took place in 2001 as a response to a call from the United Nations Environment Programme (UNEP) to take action on POPs, and included a list of the “Dirty Dozen” chemicals, which were designated as the “worst offender” chemicals. In 2009, a second set of 9 chemicals were added as the “new POPs”. China is a party to the Stockholm Convention, and thus has shown commitment to eliminating the production and use of the listed POPs.

Molecular structure of PFOS, one of the "new POPs" as designated by the Stockholm Convention for its persistent, bioaccumulative, and toxic properties

My research focused on one of the “new POPs”, called perfluorooctanesulphonate (PFOS), which is a fully fluorinated eight carbon chain with a sulfonic acid head. Because this chemical is both oleophobic and hydrophobic (exclusion of both non-polar oils and polar water), it was historically used as a surfactant and coating for many products, including fabrics and carpeting. The most common product utilizing PFOS was produced by 3M, and called Scotchgard™. In addition, it is commonly used as a processing aid in industries including metal plating, and paper treatment, and as a key ingredient in aqueous fire-fighting foams (used to combat fires fueled by highly flammable gases or liquids).

In 2000, 3M, then the largest producer of the parent compound Perfluorooctane sulfonyl fluoride (POSF), announced the discontinuation of all its PFOS-related products because of the chemical’s toxicity to humans and the environment. Shortly thereafter, most other countries followed suit and banned the production of the chemicals. However, because of a lack of appropriate substitutes and technical transfer, China continues to be the only country still reported to be producing POSF and utilizing PFOS, despite its entrance into the Stockholm Convention.

Relatively speaking, China has only produced a small amount of POSF compared to 3M, however, there the true effects of this contaminant are still not determined because of incomplete emissions inventory, which is typically needed to be able to assess a contaminant’s effect in a certain region. Mostly, there is no existing, complete centralized record of exactly which industries are still utilizing PFOS. The first part of my research was to determine the key areas in China for which more investigation investment would be likely to contribute the most emission of PFOS into the environment. I designed a emissions inventory methodology specific to the contamination patterns of PFOS in the Chinese environment that grouped lifetime product releases into wastewater treatment plant effluents, while determining key industries for further investigation. Wastewater treatment effluent concentrations were determined to exhibit a correlation with more easily-obtainable geo-referenced data, such as population density and city GDP. This way, an estimate of PFOS emission can be extrapolated without having to test every city’s wastewater effluents.

A schematic for the emissions scenario I designed for back calculating source load from environmental concentrations

While designing the emissions inventory methodology, I found that China-specific industrial data and emissions factors are greatly lacking, but that environmental monitoring concentrations are much more available for a wide range of areas within China. Therefore, utilizing these environmental concentrations, I developed a unique multimedia fugacity model to estimate source load in a given area, given PFOS’ physical-chemical properties and the hydrological conditions of the modeled area. I completed a case study example and successfully proved my model’s stability for a segment of the Huangpu River in Shanghai.

In addition, also using the available environmental monitoring concentrations, I also carried the first national probabilistic risk assessment for PFOS in China. Probabilistic risk assessment is different from deterministic risk assessments, which have been performed in the past, in that it is able to incorporate spatial and temporal variability. Based on toxicity data reported in the literature, I also derived a predicted no effect concentration range (PNEC) by which to evaluate the conservativeness of previously reported PNEC values.

Me, at the 100th Anniversary Celebration of Tsinghua University at the Great Hall of the People, Beijing, China

Me and Yang Liwei, first Chinese taikonaut in space at the 100th year anniversary of Tsinghua University at the Great Hall of the People, Beijing, China

I enjoyed my two years at Tsinghua University. Aside from my research, I participated in many of my research group’s and school activities. This year was the 100^th Anniversary of the founding of the university, and I was chosen as a representative of the School of Environment to attend the celebration at the Great Hall of the People, where President Hu Jintao (alumus of Tsinghua University Hydraulic Engineering) spoke, along with the presidents of Tsinghua University, Peking Univeristy, Yale University and student and faculty representatives. This year was also the first year that The Department of Environmental Science and Engineering became the School of Environment, an event that represents the growing importance of environmental issues in China and the country’s commitment to training the country’s best and brightest to help solve some of China’s most pressing environmental challenges.

Ruins of the Old Summer Palace in Beijing, China

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.

A worker covers an impermeable plastic membrane with soil in the bed of a lake in the Old Summer Palace. Source: Xinhua News Agency

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

Map of the lakes within the Old Summer Palace and location in China. Source: On sealing a lakebed: mass media and environmental democratisation in China. Ji Ma, 2009

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.

My best friend lives in St. Thomas. When I visited her last year, I was amazed that ALL of the water she used was rainwater from a rooftop catchment system.  I was there for 10 days and in that time quickly adapted to “West Indian Showers” (turning on the water only for a few seconds at and the beginning and end of your showering process), using the absolute minimum amount of water for dishwashing, and learned the phrase “in this land of fun and sun, we don’t flush for number one!”

Picture from sign in bathroom of Soggy Dollar in Jost Van Dyke, BVI Source: http://www.flickr.com/photos/jplatti/699933176/in/photostream

Although the island life takes a little getting used to, when I returned home I was SO conscious of just how much we, as a society, waste water.  My roommate would defrost chicken by running cold water over it- for hours! Despite my complaints and explanations of why it was wasteful, she couldn’t understand that water is a precious resource.

Compared with other developed countries, the United States has some of the lowest water/wastewater costs as a percentage of household income.  I know that when I became responsible for paying gas and electricity bills, our thermostat turned down and I became much more conscious of conserving energy.  As a renter, I have still never had a water bill in my name, as is the same for most young people.  Water seems free, and even for my landlord who is footing the bill; it is a very low cost utility.

At present, the cost of water does not reflect the value of the resource.  Water infrastructure is aging and revenue generated from the sale of water is needed to improve water services.  Increasing the price of water will not only generate revenue to improve the infrastructure but should also help to make the public understand that water is a valuable and precious resource.

In the United States, we are lucky to have infrastructure for delivering water conveniently and cheaply to our faucets. However, it takes a huge amount of energy to transport and treat water.  Rainwater is an under-utilized resource that can be used as potable water without extensive pumping and treatment.

In many areas of the world, rainwater is used for everything: showering, drinking, dishwashing, irrigation and toilet flushing.  However, in developed countries, which do have advanced water infrastructure, rainwater is generally used only for non-potable uses such as irrigation, toilet flushing, laundering, emergency water supplies, fire prevention use and process water uses.

Rainwater harvesting is a very scalable technology that can be as simple as catching rainwater from the roof and delivering it to storage tanks for irrigation or can be as complex as a large cistern with treatment processes for indoor use.  It is important to match the rainwater use to the level of treatment provided.  Water used for irrigation does not need to be treated to potable water standards, as that would be a waste of time, energy and money.  However, if the water will be used indoors, it is important to insure that it is adequately treated to mitigate health concerns.

Simple rainwater catchment system Source: http://www.town-menasha.com/CDWeb/Planning/Stormwater/BMPs.htm

Complex rainwater harvesting system with ozone and UV treatment Source: http://www.spartanwatertreatment.com/rainwater-harvesting-water-treatment.html

There are so many benefits of rainwater harvesting! These include (but are not limited to): minimizing stress on municipal systems (supports supply and reduces infrastructure maintenance costs); reducing energy required for treatment and pumping of centralized systems (thereby reducing greenhouse gas emissions); providing independent water security especially in times of natural disaster; often providing cost savings over time; decreasing municipal stormwater intake (thus reducing flooding, lessening quantity of stormwater needing treatment, and minimizing sewer overflow); and offering community benefits such as open green areas, public water awareness and self sufficiency.

Although using rainwater can be very beneficial, it is important that the catchment systems are designed well and with caution.  Most concerns are related to health concerns from biological or chemical contamination. However, in good designs most of these worries are minimized.  It is important that municipalities recognize the benefits of rainwater harvesting and create guidance to encourage safe catchment system design. Equally important is for citizens to use these regulations when building a system.   Lastly, it is important that systems are inspected regularly to insure against contamination and to ensure that the water stays at a healthy pH level.

In conclusion, it is important to grow awareness in many developed countries about the scarcity of water.  One way of doing this is by raising water prices to full-cost pricing.  Once people become more conscious that we need to look at other water sources, hopefully rainwater harvesting will become more popular.  Rainwater catchment systems are very scalable and have many benefits, but most be designed cautiously to ensure the rainwater remains safe.  Hopefully, systems will become more prevalent to reduce the impact on current infrastructure and to ensure security to our water systems.

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!

Water Recycling Treatment and Uses. Source: http://www.epa.gov/region9/water/recycling/index.html#uses

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 Reclamation Diagram. Source: http://science.howstuffworks.com/environmental/green-science/gray-water-reclamation.htm

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.

Oasis Laundry Detergent, safe for wash water recycling. Source: http://www.amazon.com/Oasis-Laundry-Detergent/dp/B001KWGW3G

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.

It does not do the work of the design team, but rather sets goals and provides the framework for a green building project.  I believe that it has also helped to advance the use of sustainable practices by providing a recognized benchmark, which has market value.

The LEED Green Building Rating System is a point system based on the following categories: sustainable sites, water efficiency, energy and atmosphere, materials and resources, indoor environmental quality, innovation in design and regional priority.

There are 100 possible credit points in each of the first 5 categories.  Innovation in design and regional priority credits allow for up to 10 bonus points.  Based on how many points a project obtains, it will receive a certification, silver, gold or platinum status.

LEED Point System. Source: http://www.usgbc.org/DisplayPage.aspx?CMSPageID=1991

While studying I was particularly interested in the water efficiency category and decided to get a more detailed understanding of the LEED credits by re-reading the chapters on water conservation and supply and integrated water management in Sustainable Infrastructure: The Guide to Green Engineering and Design.

In this blog I write about the water efficiency credits for LEED certification, and in subsequent posts I will go into further detail about some of the strategies that LEED recommends.

The water efficiency category for LEED certification provides benchmarks to reduce water usage and provides suggestions to accomplish this, such as, using efficient plumbing fixtures, using graywater or captured rainwater for non-potable uses, applying xeriscape landscaping techniques and installing sub-metering devices.

Water Efficiency Points. Downloaded at http://www.usgbc.org/DisplayPage.aspx?CMSPageID=220

The most environmentally and wallet friendly way to protect water resources is to simply reduce demand and conserve water.  LEED addresses this by suggesting low-flow faucets, showerheads, and toilets, dual flush toilets and waterless urinals.  The Bank of America headquarters in New York City, which achieved platinum certification in 2008, estimates saving 3.4 million gallons of water per year by using waterless urinals and 1.1 gallons per year with low-flow bathroom fixtures!

LEED also suggests decreasing water usage by using non-potable water.  Non-potable water is water that does not meet drinking water standards set by the Environmental Protection Agency (EPA), but can be used for purposes that do not come into human contact. Sources of non-potable water include captured rainwater, stormwater, and graywater.   Using non-potable water for irrigation purposes is the safest and easiest use, especially using sub-surface irrigation. However, it can also be used indoors for toilet flushing and process water (cooling towers, boilers, chillers and commercial kitchen use).

In addition to using non-potable water for irrigation applications, we can minimize water usage for landscaping by choosing native plants and applying xeriscaping.  Xeriscaping is a type of landscaping which emphasizes minimal water use, soil improvements, mulching and efficient irrigation.  Designers should also use efficient irrigation equipment; for example: sprinkler systems are only 65% efficient while drip systems are 90% efficient.

Xeriscaping Landscape Design: Source: http://home.howstuffworks.com/lawn-garden/professional-landscaping/alternative-methods/xeriscaping.htm

Lastly, LEED suggests installing sub-metering devices for indoor, outdoor and process uses.  Sub-metering is useful for monitoring water use, identifying leaks or problems, and tracking peak periods of water use.  Most sub-metering devices track cold, potable water use.

Strategies such as “use low-flow plumbing fixtures” or  “install sub-metering” are relatively self-explanatory and do not require much design engineering.  However, utilizing graywater, harvesting rainwater and treating wastewater can be much more intensive strategies.   To understand these techniques, I turned to Sustainable Infrastructure: The Guide to Green Engineering and Design. In upcoming posts I will describe these methods in more detail.