Tag: water treatment

World Water Week 2017 – Water and Waste: Reduce and Reuse

world-water-weekWorld Water Week is an annual event organized by the Stockholm International Water Institute (SIWI) that focuses on global water issues, and this year’s theme is “Water and Waste: Reduce and Reuse.” The main event takes place in Stockholm, Sweden where experts, innovators, stakeholders, and young professionals from various sectors around the globe will come together to share ideas, foster relationships, and develop innovative solutions to the world’s most urgent water-related problems. In 2016, over 3,300 individuals and over 330 organizations from 130 countries around the world participated in World Water Week, and the expectation is that 2017 will see at least those numbers. Through this year’s theme, World Water Week is focusing on two targets addressed by the Sustainable Development Goals (SDGs) of the UN’s 2030 Agenda for Sustainable Development including improving water quality and reducing waste by 2030 in order to help achieve sustainable development in a rapidly changing world.

Sustainable Development

Sustainable development is most commonly defined as development that meets the needs of the present without compromising the ability of future generations to meet their own needs. This means that we cannot meet our current needs at the expense or depletion of our natural resources. Degradation of water quality not only has a negative environmental effect, but also limits the water supply available for human usage. Therefore, we must develop and implement innovative solutions to improving water quality if we are to plan for a sustainable future. Fortunately, there exist easily implementable methodologies for improving water quality throughout the water environment.

Utilize mores sustainable water treatment technologies that limit environmental impact

Chemical additives have a significant impact on the health of the environment and its inhabitants. Implementing alternative treatment methodologies such as ozonation, ultraviolet radiation, and biological media helps to minimize the impact that water treatment has on our natural world, and protect our water supply for the future.

 

Minimize, and eventually eliminate, using drinking quality water for non-potable purposes

Producing drinking quality water utilizes a significant amount of energy, resources, and treatment chemicals, all of which have a negative impact on the environment. Minimizing the use of potable drinking water for other functions, including agricultural, industrial, and non-potable residential, helps to ease the burden placed on resources, the environment, and budgets.

Reduce lost water in municipal distribution systems

Communities lose millions of gallons of water each year to leaks in the distribution system. While replacing compromised pipes seems like an easy solution, the problem is actually much more complicated. Municipalities do not have sufficient funds to implement large-scale replacement projects; therefore, many compromised pipes remain in use, contributing to distribution system water loss. This loss results in reduced supply, which in turn forces some systems to seek alternate sources at a cost to both the environment and their budgets.

Conducting water audits and pipe condition assessments should be the first step towards efficient, cost-effective pipe replacement programs. Water audits help to identify the causes of water loss while developing strategies to reduce this loss, while pipe condition assessments provide insight into the quality and reliability of water distribution systems. Drinking water infrastructure in the United States, particularly in the northeast, is typically many decades-old, and deteriorating distribution systems can be a significant source of water loss through leakage. Effective water loss control programs reduce the need for facility upgrades and expansions, and in many instances, can reduce the need to find additional sources. In addition, a water loss control program can help protect public health by reducing the number of entry points for disease‐causing pathogens.

Incorporate stormwater best management practices into the built environment

Rain gardens help manage stormwater with minimal impact to the environment

Stormwater management traditionally meant infrastructure such as catch basins. Modern day stormwater management takes a much more holistic approach and maximizes the use of both the natural and engineered landscape. Some examples include onsite catchment and use, reduction of impervious surfaces, stormwater engineering such as bumpouts and tree boxes, and stormwater landscaping such as rain gardens and grassed swales.

Minimize stormwater pollution

Stormwater pollution occurs when precipitation picks up debris, trash, fertilizers, animal waste, pesticides, and improperly discarded chemicals as it moves over the ground. Reducing fertilizer and pesticide usage, cleaning up after pets, and ensuring that trash and chemicals are disposed of properly help to reduce the amount of contamination entering our waterways.

Reuse wastewater

After adequate treatment of wastewater to remove all pollutants and pathogens, it should be reused as much as possible. Treated byproducts can be used for fertilizer and methane fuel, and highly treated water can be reused for aquifer recharging, and even for drinking water.

And of course – educate!

Promote conservation, efficiency, and innovation in water use by incentivizing water conservation, implementing public outreach and education, and encouraging the adoption of methodologies and the usage of products that utilize the latest in water-efficient technologies.

In Conclusion

Achieving sustainable development is only achievable if we focus on the protection of our natural resources at every level. From improving treatment plant efficiency to installing WaterSense fixtures in our homes, creating a truly water wise future requires involvement from governments to individuals on a global level. Since 1991, World Water Week has served as a forum for legislators, scientists, experts, and interested parties to form partnerships and alliances, and to collaboratively find solutions to today’s most urgent water-related issues.

The Importance of Energy Efficiency in Water and Wastewater Treatment – Case Studies

As those in the industry well know, water and wastewater treatment plants use an exorbitant amount of energy. In fact, 30-40% of total municipal energy consumption is due to water and wastewater treatment plants. In addition, energy currently accounts for 40% of drinking water systems’ operational costs and is projected to jump to 60% within the next 15 years. This excessive energy consumption places financial burden on already stressed water and wastewater utilities struggling to keep up with ever-increasing regulations and demand.

MBR membrane installation

The Electric Power Research Institute (EPRI) conducted studies on wastewater treatment plants and cautions that as treatment requirements increase, energy requirements will also increase. EPRI also projects that as treatment requirements increase, the energy required to treat wastewater utilizing conventional technologies will increase exponentially. For example, new membrane bioreactor (MBR) processes actually consume 30-50% more electricity than plants that utilize more advanced treatment with nitrification. Also, plants that incorporate nanofiltration or reverse osmosis to meet stringent effluent utilize nearly twice the energy. EPRI further projects that strict nitrogen and phosphorus removal will be increasingly required, necessitating the incorporation of these energy-intensive technologies.

And let’s not forget the environment. Drinking water and wastewater systems add over 45 million tons of greenhouse gases annually, contributing to the already problematic issue of climate change. Bringing the issue full circle, climate change directly affects both the availability and the quality of our drinking water supply. The importance of incorporating energy efficiency into water and wastewater operations is paramount to these systems’ future sustainability.

Case Studies

Canaan, VT and Stewartstown, NH Shared Wastewater Treatment Plant Upgrades

The new Canaan, VT Stewartstown, NH shared wastewater treatment plant

The Towns of Canaan, Vermont and Stewartstown, New Hampshire operate a shared wastewater treatment facility, which required significant upgrades. The existing facilities were 40 years old and although a few upgrades were performed in the 90s, the facilities were not performing well, did not meet Life Safety codes, and required significant maintenance.

One of the primary elements of the design was the consideration of the economics of energy reduction.  The design incorporated insulated concrete form construction for the building walls with R-49 insulation rating in the ceilings.  The design also included a wood pellet boiler with a pellet silo and hot water heating system, which allowed for reduction of explosion proof heaters in the headworks building.  All of the windows were low-E and highly insulated, and an outer glassed-in entry way increased the solar gain retention of the building and reduced heat loss.  The process headworks and operations buildings were constructed as single story structures, increasing operator safety.  The lagoon aeration system is now a fine bubble, highly efficient process with additional mixing provided by solar powered mixers that help reduce aeration requirements, improve treatment, and allows for the addition of septage, all at no cost due to solar power.

Solar mixers for lagoons

The pump station upgrades were designed to eliminate daily confined space entry by the operator by the conversion to submersible pumps.  For sludge removal, a unique and simple “Sludge Sled” system was incorporated, which allows the operators to easily remove the sludge at their convenience. Sludge treatment is accomplished with a geo-bag system that allows the sludge to be freeze dried, reducing the volume by almost 50% with no energy consumption. The influent pump station was designed with three pumps instead of the normal two-pump system in order to meet both present and future design flows, allow for lower horsepower pumps, improve flexibility, reduce replacement costs, and reduce energy costs.   The other four deep dry pit pump stations were converted to wet wells and submersible pumps, eliminating confined spaces, and are equipped with emergency generators, eliminating the need for operator attention when power is lost.

The incorporation of highly energy efficient building components resulted in reducing annual operation and maintenance costs, which resulted in a more sustainable facility. All of the equipment and processes were thoughtfully selected to reduce both annual and future replacement costs.

wastewater treatment facility improvements whitepaper
Click above to download the complete whitepaper on this important project.

The treatment system is a 3-cell aerated lagoon system, and the solar powered mixers were installed to enable reduction of the aeration needs and horsepower during the summer months when septage is added.  The aeration blowers, which are housed in insulated enclosures, reduce noise and were sized to allow for the addition of septage to the lagoons, which is not common in Vermont.  The aeration blowers are controlled with Variable Frequency Drives (VFDs), which allow for greater operator control of aeration and provide energy cost savings. The operation is simple and safe for operators and others who need to maintain the facility and equipment.  The design has provided flexibility to the operators and has resulted in an energy efficient, sustainable solution for this community.

The project received an Engineering Excellence Merit Award from the American Council of Engineering Company’s Vermont Chapter in 2017.

Shrewsbury, MA Home Farm Water Treatment Plant Design

Excavation for the new 7.0 mgd Home Farm Water Treatment Plant began in July 2017

The Home Farm Water Treatment Plant (WTP) in Shrewsbury, Massachusetts was originally constructed in 1989. Although the WTP is still fully functional, its treatment capabilities are limited to chemical addition and air strippers for VOC removal, and the plant is capable of treating 6.0 million gallons per day (mgd). Manganese is present at all Home Farm wells, with widely varying levels from a low 0.03 parts per million (ppm) to a high 0.7 ppm. The existing treatment plant sequesters manganese, but does not have the ability to remove it from finished water.

Three treatment methodologies were piloted. The first two were greensand and pyrolucite, both commonly implemented catalytic media options for removing manganese and iron. The third was Mangazur®, a new technology. Mangazur® filter media contains the microscopic organism leptothrix ochracea, which consumes manganese and is naturally occurring in groundwater. Through consumption, the microbes oxidize the manganese to a state where it can precipitate onto the media. Unlike other media, Mangazur® does not require regeneration due to the continuous growth of microbes within the filter. Mangazur® technology also does not require chemical addition for pre-oxidation, minimizing the amount of chemical required for the plant.

Pilot testing for the biological treatment was performed over five one-week trials. Test parameters included a long shut-down on the filters, adding pre-oxidant, and adjusting pH or dissolved oxygen. The results of the testing indicated that although the Mangazur® does require a correct dissolved oxygen level and pH, it does not require a pre-oxidant, making the only chemical addition necessary for pretreatment potassium hydroxide for pH adjustment. Filter backwash efficiency is also a major benefit of the Mangazur® technology for the Home Farm application. With loading rates twice that of traditional catalytic media and filter runs exceeding 96 hours, the Town would only need to backwash the four filters once every four days rather than eight filters every day, saving a significant amount of water. The backwash flow rate and duration are also significantly lower for Mangazur® filters than for other traditional filter options. The results of the pilot tests indicated that all technologies were viable options to reduce manganese levels below 0.05 ppm; however, the biological treatment was the most efficient option.

Since the existing chemical feed equipment in the plant is aging and the existing building itself was also in need of rehabilitation, the decision was made to construct an entirely new standalone 7.0 mgd facility. The new facility will feature many energy efficient features including translucent panels for lighting efficiency, high efficiency water fixtures, high efficiency lighting, and stormwater bioretention areas for drainage.  In addition, while the existing building will be demolished, the concrete slab slab will be kept for future installation of solar panels. The new facility also contains three deep bubble aerators for VOC removal. While Mangazur® technology has been approved in one other municipality in Massachusetts, there are few treatment plants in the northeast using this technology, and of those treatment plants, none have a design capacity above 5.0 mgd.  Home Farm has a much higher design capacity and will be the largest Mangazur® water treatment plant in the northeast once completed.  The Mangazur® filters at Home Farm will have the second highest design capacity in the country, after a 26.0 mgd treatment plant in Lake Havasu City, Arizona.

Download the complete whitepaper on the Mangazur™ Home Farms Water Treatment Plant here.

Flagstaff, AZ Water Reclamation Facility Upgrades

Tata & Howard provides on-call engineering services for water, wastewater, and energy related projects for the City of Flagstaff, Arizona. Several options for replacement of the blowers were evaluated and presented to the City in a report that recommended the installation of appropriately sized turbo blowers and upgrading the controls logic to automate dissolved oxygen controls.

The City had been experiencing long term maintenance issues with the existing biogas piping at the Wildcat Wastewater Reclamation Facility. The piping to the co-generator was not providing an adequate supply of gas from the digesters which, if operating, could save the City approximately $200,000 in annual power costs. The goals of this project were the restoration of the ability to run the generator on biogas, utilize the heat generated by the sludge digestion process to further reduce energy costs, reduce maintenance time to operate the biogas system, and have a positive impact on the environment, since methane is one of the most potent greenhouse gases.

Wastewater treatment plant in Flagstaff, AZ

In addition, Tata & Howard conducted an energy efficiency study on the aeration blowers and pumps at two treatment plants. Pumping systems had efficiencies as low as 20%. Pumps and blowers were oversized to meet peak and future demands but not efficient at low flows or off peak flows. The testing showed that modifications to these systems had the potential to save the City approximately $250,000 in annual electrical costs and $445,000 in APS rebate funds for the modifications.

Download a case study on the energy efficiency project in Flagstaff, AZ here.

In Conclusion

While these three case studies are all extremely different projects, the goals are the same: increased energy efficiency, greener operations, and sustainability, all while meeting project objectives, budgets, and deadlines. Increasing energy efficiency in water and wastewater treatment is no longer optional; rather, it is a necessity to remain operational by meeting both budgetary and sustainability objectives. By incorporating innovative thinking and tailored methodologies into rehabilitation and repair projects, water and wastewater systems can ensure sustainable operations and a greener environment while protecting our world’s most precious resource for generations to come.

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The Importance of Treating Manganese in Drinking Water

Manganese in drinking water has recently come under scrutiny due to its potential toxicity as well as its damage to distribution systems. A mineral similar to iron and common in Earth’s crust, manganese is found in about 95% of New England water supplies. While low concentrations are not only safe but also beneficial to human health, elevated manganese concentrations can cause taste and color issues, health risks to customers, and problems for distribution systems.

manganese-water-map
Map of soil manganese content in the U.S. (red = high manganese areas). Courtesy of U.S. Department of the Interior, U.S. Geological Survey, Mineral Resources.

Health Effects of Manganese

manganese-bloodManganese is an essential nutrient at about 2.5-5.0 mg/day, but overexposure can potentially cause serious health issues. Long term exposure to manganese can cause toxicity to the nervous system and Parkinson’s like symptoms – particularly in children, the elderly, and pregnant mothers. Young children and infants cannot break down manganese in their bodies as effectively as adults, which can cause issues in early brain development.  In recent studies, children exposed to high levels of manganese experienced learning difficulties such as ADD, hyperactivity, Pervasive Development Disorder, and memory issues. Another interesting effect of overexposure to manganese is violent behavior. Studies have shown excessive manganese decreases serotonin function and reduces dopamine levels, resulting in social withdrawal, increased depression, and aggression. Studies completed in prisons have concluded manganese toxicity contributes to delinquent behavior, and autopsies of mass murderers often show toxic levels of manganese. While these studies may be concerning, manganese ingested through drinking water is processed by the liver and reduces the risks associated with other forms of manganese exposure, such as inhaling.

State and Federal Guidelines for Manganese

manganese-oxide
Manganese oxide in rock

There are currently no enforceable federal drinking water standards for manganese. The US Environmental Protection Agency (EPA) has a secondary standard of 0.05 mg/L, a standard established to address issues of aesthetics such as discoloration, rather than health concerns. In the absence of an enforceable federal standard, the Connecticut Department of Public Health (CT DPH), has set their Action Level at 0.5 mg/L, whereas the Massachusetts Office of Research and Standards has set an Office of Research and Standards Guideline Limit (ORSGL) of 0.3 mg/L for lifetime exposure by adults and acute exposure (ten days) by infants less than one year of age.

Saving the Distribution System

Manganese-deposits-water-mainManganese deposits can build up in pipelines, pressure tanks, water heaters, and water softeners, reducing the available quantity of the water supply and pressure in the system. Manganese accumulations can become expensive for utilities when water supply or water softening equipment must be replaced. Also, energy costs can become a burden for utilities when pumping water through constricted pipes or heating water with heating rods coated with manganese deposits. Managing safe levels of manganese in drinking water is an important step in preserving valuable assets in a distribution system. The benefits associated with treating manganese greatly outweigh the long-term repair and rehabilitation costs utilities may face with high levels of manganese. To adequately manage safe levels of manganese, proper water treatment is paramount.

Proper Testing

For managing manganese in drinking water, the best treatment method is dependent on several factors including manganese concentrations, the presence of other contaminants, and existing treatment methods. Therefore, accurate testing is important before considering options or selecting treatment equipment. Typically, tests are conducted to quantify the extent of manganese concentrations, but testing of additional water parameters such as pH, oxygen content, hardness, iron, and sulfur may also be useful to determine the most appropriate water treatment method.

Phosphate Treatment

new-engljand-waterFor low concentrations of manganese, 0.3 mg/L or less, sequestering utilizing phosphate compounds is a simple, effective, and inexpensive solution. When added to water, phosphate compounds surround minerals and keep them in solution. When these compounds are put into the water system, they stabilize and disperse dissolved manganese. As a result, the manganese is not available to react with oxygen to create issues with the color, taste, or odor of drinking water. The phosphate compounds must be introduced into the water at a point where the manganese is still dissolved to maintain water clarity. This treatment process should take place before the pressure tank and as close to the well discharge point as possible. Phosphate treatment does come with a bit of risk due to the instability of most phosphate compounds at higher temperatures. If phosphate-treated water is boiled or heated, such as in a water heater, the compounds have the potential to break down and release manganese that could react with oxygen and precipitate. Also, phosphates from any source contribute to excess nutrient content in surface water.

Oxidation Followed by Filtration

manganese water treatment public
Tata & Howard completed pilot testing, design, permitting, bidding, and construction management services for the Town of Wayland’s Baldwin Pond Water Treatment Plant which included iron and manganese removal.

Among the most common forms of manganese treatment is oxidation followed by filtration. This form of treatment is ideal for manganese concentrations greater than 0.3 mg/L, where sequestering is not an option. During this process, an oxidizing chemical, often potassium permanganate, chlorine, or ozone, is pumped into the water by a small chemical metering pump that operates simultaneously with the well pump. This step converts soluble manganese into an insoluble, filterable form.  Typically, the chemical is injected in a pipeline prior to the filters, providing sufficient contact time to allow oxidation to take place. The resulting solid particles then must be filtered. Therefore, a media, membrane, or biological filter is necessary for the removal process. Common media filters include GreensandPlus and LayneOx®; membrane filtration technologies include microfiltration, ultrafiltration, and nanofiltration; and biological filtration technologies include Mangazur®. While the process may seem simple, it is important to monitor both the source water and treated water to determine the proper oxidation dosage and confirm the removal efficiency.

In Conclusion

When managing manganese levels in drinking water, it is imperative to have a well-executed balance between maximizing quality while minimizing costs. While there are many different methods to treat manganese in drinking water, the best first step to take is proper testing and an evaluation of the distribution system. Every system is different and may require unique treatment or even new source development. Manganese poses a problem for both communities and utilities alike, and proper mitigation protects the health of water system customers while greatly increasing the condition and life of the water distribution system.

Ryan Neyland, P.E. Project Manager, has over 11 years of concentrated water treatment experience including all phases of planning, design, and construction services, as well as pump station rehabilitation and SCADA experience. He holds a BS in Civil Engineering from Worcester Polytechnic Institute.

 

Giving Thanks – for Water!

It is widely known how important water is to our lives and the world we live in. Our body and planet is comprised of about 70% water – making it seem like it is easily accessible and plentiful. However, when you rule out our oceans and ice caps, less than 1% of all the water on Earth is drinkable. Of that less than 1%, groundwater only accounts for 0.28% of fresh water around the globe. Safe drinking water is a privilege we often take for granted while we brush our teeth or drink a glass of water in the morning. While we are giving thanks to our family, friends, and food during Thanksgiving, we should also give big thanks for our clean drinking water and the people who make it happen.

The Importance of Clean Water 

hauling_water_in_malawi
Villagers in Malawi travel miles to find and transport water which is rarely safe for human consumption.

Keeping yourself hydrated can do wonders for your health. The benefits water provides for our bodies range from relieving headaches, flushing toxins out of the body, improving mood, helping with weight loss, and relieving fatigue. In the U.S., we are fortunate enough to have some of the cleanest drinking water anywhere in the world to keep us healthy and safe. In other countries and for some 783 million people, that is not the case. Many do not have access to sufficient drinking water and the water they do have often contains dangerous pathogens. Often, unclean water sources are miles from villages and some people are forced to spend hours each day simply finding and transporting water. The typical container used for water collection could weigh between 40 and 70 pounds when filled. Imagine how difficult it would be to carry the equivalent of a 5-year-old child for three hours out of each day just to have water to drink. With so many people not having access to clean drinking water around the world, it is important to appreciate the plentiful and safe drinking water we have here in America.

W_WW_treatment_INFOGRAPHIC
A visual diagram of water and wastewater distribution systems. Click the image to see full size.

A Special Thanks for the People Who Make Our Water Safe

When looking at America’s clean water, it is especially important to give special thanks to the water and wastewater utilities that work nonstop to give us some of the cleanest drinking water in the world. Despite the fact that our country has beautiful rivers and lakes, the water that comes from them to our taps goes through several processes that require a lot of work and maintenance. Our water and wastewater utilities maintain some of the highest standards in the world when it comes to drinking water, and new innovations for treatment and distribution are always being researched and implemented. Water and wastewater employees work tirelessly to meet regulatory requirements and preserve local waterways despite major setbacks like deteriorating infrastructure and shrinking funding for necessary projects. On top of treating our water, utilities are responsible for keeping their distribution systems running efficiently and also to being stewards to the environment through improving effluent quality. Our water utilities are arguably the most important utilities in the nation because water is so crucial to our survival.

In Conclusion

We are so incredibly fortunate here in the United States to not have to think twice about the purity of water from the tap, a glass of water in a restaurant, a highway rest stop, an airport, or motel – all thanks to our water and wastewater utilities. For that, we should be especially thankful. This Thanksgiving, be sure to give special thanks for having safe drinking water and to the dedicated, hard-working people at water and wastewater utilities.

Water and Wastewater Treatment Infographic

Water and Wastewater Treatment Infographic

Municipal water and wastewater treatment is a specialized and involved process that focuses on keeping communities healthy and safe. Feel free to download and share, with attribution. For a printable, high resolution version of the water and wastewater treatment infographic, please click here.
wastewater_treatment_infographic

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Desalination: a viable option?

iceberg for water supply
Some people have suggested towing icebergs to places that need freshwater. Photo: SERPENT Project

Drought. Scarcity. Pollution. Climate change. Demand. Overpopulation. These are all issues with our nation’s water supply with which we have become all too familiar. Engineers and water systems are scrambling for solutions, and countless possibilities — some as basic as conservation and water bans and some as complicated as water reclamation and transporting icebergs — have been considered. Communities struggle to meet demand with dwindling supply and a limited budget, and many have begun to give desalination serious consideration.

Desalination, or the process of removing salt from water, used to be summarily dismissed as a supply option due to its expense and energy consumption. However, in light of the increase in water scarcity, desalination has become a feasible option for many water-stressed communities. Already commonplace throughout the Middle East, desalination plants are now popping up all over southern California and Texas. Let’s look at some facts about global desalination:

  • carlsbad desalination plant
    When complete, the Carlsbad, CA desalination plant will be the largest in the western hemisphere

    Dubai sources over 98% of its potable water supply from desalination

  • Global leaders in desalination are Saudi Arabia with 17% of global output, United Arab Emirates with 13.4%, and the United States with 13%
  • Nearly 70% of Israel’s domestic water consumption comes from desalination
  • Most desalination plants are in the Middle East, where energy is less expensive and environmental regulations are less stringent
  • Currently under construction, the $1 billion, 50 mgd Carlsbad desalination plant in Carlsbad, CA will be the largest in the western hemisphere when completed
  • Costing $2 billion, the Sydney, Australia desalination plant has not produced any water since 2012 due to high dam levels

desalination diagramThe most commonly utilized desalination technology is reverse osmosis (RO), which was invented in California in the 1950s. RO uses high pressure to force water through fine membranes that leave the salt behind. For every two gallons of salty water, only one gallon is made available as freshwater. The whole process utilizes an exorbitant amount of energy, with energy accounting for up to half the total cost of desalination. In fact, desalinated water costs about $2,000 per acre-foot, which is approximately the amount of water used by a family of four in six months. Because less salty water requires less energy for processing, the most cost-effective desalination plants treat brackish, or slightly salty, water rather than seawater.

desalination fish
Impinged fish

There are some environmental concerns surrounding desalination as well. The highly concentrated salt brine left behind requires disposal. However, because it is twice as dense as seawater, it sinks to the ocean floor and spreads, suffocating bottom-dwelling marine life. Therefore, the brine byproduct must be mixed with freshwater, typically in the form of treated wastewater or cooling water from a power plant, prior to being released into the ocean. In addition, fish and other marine life are often sucked toward the intake pipes where they are killed on the intake screens (impingement), and smaller marine life, such as plankton, larvae, and fish eggs, pass through the screens and are killed during the desalination process itself (entrainment). Fortunately, there have been some recent innovations to address these concerns. For example, subsurface intakes pull seawater from beneath the seafloor, virtually eliminating impingement and entrainment. An added bonus to subsurface intakes is the fact that the sand acts as a natural filter that pre-filters the water, reducing the plant’s chemical and energy usage.

central_valley_california
California’s Central Valley is largely agricultural and relies heavily on irrigation

This summer, HydroRevolution, a subsidiary of San Francisco-based agricultural and commercial water producer WaterFX, announced its plans to build California’s first commercial solar desalination plant in the state’s heavily agricultural Central Valley. The plant will run solely off solar thermal energy and will utilize Aqua4, a new desalination technology that produces only solid salt and freshwater, with zero excess discharge. In addition, it will utilize unusable irrigation water from a 7,000-acre ditch rather than seawater. The plant will provide the necessary freshwater for the area’s irrigation needs without the energy consumption or concentrated briny discharge of traditional desalination plants. Admittedly, having the 7,000-acre ditch from which to draw the water helps immeasurably, and isn’t an option for most other areas.

But desalination isn’t only being used in the southwestern part of the country. In Massachusetts, the Town of Swansea recently opened the first publicly held desalination facility in the Northeast. A coastal town, Swansea experienced a population boom that led to groundwater supplies running low, which in turn allowed seawater to seep into the aquifers. The result was a water crisis that forced the enactment of water bans, steep fines – and even left 30% of the town without water for a brief period one summer.

According to Robert Marquis, who has acted as Swansea’s water manager for over 40 years, “We just couldn’t support a burgeoning population or commercial growth,” he said. “Anything that came into Swansea, we were objecting to it if it was going to be water intensive.”

Designed with the help of Tata & Howard’s own John Cordaro, P.E., the Swansea desalination facility has been online for over a year, and took home a third place global finish at the 2014 Global Water Awards, losing only to Dubai, Singapore, and Sorek, Israel.

reverse osmosis membrane
A semipermeable reverse osmosis membrane coil used in desalination

There is one matter with RO that, while a non-issue in sunny southern Californian, is a primary concern to the Northeast: RO filters are delicate and highly intolerant of ice, and cease being functional below 36°F. To address this issue, Swansea installed two miles of pipes in order to sufficiently heat the incoming river water prior to its entering the plant.

For water-stressed Swansea, desalination has been a successful solution. But nearby Brockton, Massachusetts has not realized the same benefit from their desalination facility. Costing roughly $120 million, the plant was constructed to utilize brackish river water as opposed to seawater, which Brockton officials believed would make the whole process affordable. However, seven years later, the water produced by the Brockton desalination plant is still too expensive, so the city has turned to a local lake as its source, leaving the costly desalination plant largely in disuse.

While desalination is heavily utilized throughout the Middle East, it has only recently come under serious consideration in the United States. As water scarcity increases due to population growth, climate change, and growing demand, alternative water source options are receiving close attention. Once not even considered due to energy costs and environmental concerns, desalination has become a frequent and sincere topic of conversation for meeting future needs. And with further advances in technology that address both energy usage and environmental impact, there remains a strong possibility that desalination could become a widely acceptable solution nationwide. Now if folks could just get on board with water reclamation…

5 family-friendly water and wastewater field trips in New England

Summer is here, and with it comes long, lazy days, school vacation, and, of course, family trips. When the beaches, amusement parks, and movie theaters start to get stale, why not take a water or wastewater field trip to explore the inner workings of our nation’s water and wastewater infrastructure? We’ve assembled five excellent water and wastewater field trips that are right here in beautiful New England. These trips provide STEM (Science, Math, Engineering, and Technology) education while also being engaging and fascinating. And these trips aren’t just for budding engineers. Half of all STEM jobs do not require a college degree and pay higher than non-STEM jobs with similar educational requirements.

Top 5 Family-Friendly Water and Wastewater Field Trips in New England

deer_island_wastewater
Deer Island Wastewater Treatment Plant

1. Deer Island Wastewater Treatment Plant, Boston, MA — Operated by the Massachusetts Water Resource Authority (MWRA)

The MWRA offers tours of its Deer Island Wastewater Treatment Plant on Tuesdays and Fridays from April through November. All tours begin at 9:30 a.m. and are open to adults and kids in grades 7+. But the treatment facility isn’t the only attraction at Deer Island. With 60 acres of natural open space, Deer Island offers plenty to do for the entire family, including five miles of public walkways and trails for strolling, jogging, sightseeing, picnicking, fishing, and cycling. There are ten landscaped overlooks with sweeping views of the Boston skyline and islands, handicapped accessible paths, and low impact development (LID) features including low-maintenance, native plant species. The public access area is open year-round, from sunrise to sunset. https://www.mwra.com/03sewer/html/sewdi_access.htm

Waterworks Museum, Boston, MA
Waterworks Museum, Boston, MA

2. Waterworks Museum, Boston, MA

The Waterworks Museum is located on the site of the original Chestnut Hill reservoir and pumping station and provides regional information on clean water, health, engineers, and architecture. In addition to providing the history of waterworks in the City of Boston, the museum’s Great Engines Hall houses three historic, steam-powered pumping engines, and walking tours of the reservoir itself are available. The architecturally breathtaking museum is open Wednesday – Sunday from 11am-4pm year-round, with extended “Waterworks Wednesday” hours until 9pm from April through November. Waterworks Wednesdays feature authors, concerts, and guest speakers in addition to regular tours and learning opportunities. https://waterworksmuseum.org

Ben & Jerry's "Chunkinator" converts ice cream waste into energy
Ben & Jerry’s “Chunkinator” converts ice cream waste into energy

3. Ben & Jerry’s, Waterbury, VT

From its humble beginnings in a warehouse in Burlington, VT, Ben & Jerry’s has grown to a highly successful global corporation. And while the company has exponentially increased in both size and reach, it has remained loyal to its local roots. So when it was determined that the waste created in their Waterbury, Vermont location would overload the local wastewater treatment facility, they instead decided to funnel it to two of their local dairies where it is processed in a methane digester along with other farm waste. The result? Enough biomass energy to power the farms. Unfortunately, tours of the methane digester are not available. But that’s OK, because Ben & Jerry’s offers tours of its ice cream manufacturing facility, and these tours include education on the dairy waste – as well as ice cream samples. https://www.benjerry.com/about-us/factory-tours

BONUS: Building on their commitment to green energy, Ben & Jerry’s is the first ice cream company in the world to power one of its manufacturing plants using its own waste. Located in Hellendoorn, Netherlands, the “Chunkinator” is a BIOPAQ®AFR Biodigester containing over 24 billion natural micro-organisms that turn the plant’s own ice cream waste and wastewater into biogas that fuels the plant. To date, the brightly-painted Chunkinator has produced enough power to make over 16 million pints of Ben & Jerry’s ice cream. So if you happen to be in the Netherlands this summer, be sure to swing by to check it out! https://brightfuture.unilever.com/stories/423955/THE-CHUNKINATOR–Turning-ice-cream-into-energy.aspx

Maine's stunning Sebago Lake offers something for everyone
Maine’s stunning Sebago Lake offers something for everyone

4. Sebago Lake Water Treatment Facility, Standish, ME

Maine’s Sebago Lake Region is a popular summer destination that offers camping, fishing, boating, hiking, shopping, dining, live music, theatre, and much more, and families travel from all over the country to enjoy the region’s pristine, natural beauty. While you are there, you can add a little education into the family trip by visiting the Portland Water District’s Sebago Lake Water Treatment Facility. Tours are available on the first and third Thursdays of each month, beginning at 9:30am and lasting approximately two hours, and include both the facility and the lab. Due to the technical, complex nature presented, tours are recommended for high school age and older. Located on a 10-acre site in Standish, Maine, the state-of-the-art facility utilizes screening, ozonation, UV light treatment, chloramination, fluoridation, and corrosion control. https://www.pwd.org/tours

After visiting the Stamford Water Pollution Control Authority, be sure to stop by beautiful Cove Island Park
After visiting the Stamford Water Pollution Control Authority, be sure to stop by beautiful Cove Island Park

5. Stamford Water Pollution Control Authority (WCPA), Stamford, CT

The Stamford Water Pollution Control Facility processes wastewater from Stamford and Darien, CT and discharges the treated water into the Stamford Harbor. The site has been treating wastewater since 1900, with the first plant being built in 1943. Upgraded in 1976 and again in 2006, the facility is manned 24/7/365. In response to multiple requests for tours, WPCA began offering regular public tours in 2013. Held on the second Friday of each month at 12:30pm (weather permitting), the tour includes classroom education on the wastewater treatment process followed by a walking tour of the plant to see it in full operation. Total tour time is approximately one and a half hours. In addition, comprehensive student or group educational tours for all ages can be scheduled in advance for Monday through Friday between the hours of 8am and 3pm. https://www.stamfordwpca.org/public-outreach.aspx

BONUS: While visiting Stamford, families can also visit Cove Island Park, a beautiful 83-acre beach and park on Long Island Sound that offers plenty of space for walking, biking, picnicking, or swimming, or they can even catch a ferry over to New York City.

Summer in New England is simply perfect for day tripping, and the education provided by a water or wastewater treatment plant tour is invaluable. So check out one (or more) of these five water and wastewater field trips, and let us know what you think. Happy summer!

Tata & Howard, Inc. participates in Rally for the Jimmy Fund

Tata & Howard, Inc. participates in Rally for the Jimmy Fund

Charitable event celebrates over $4 million in donations to Dana-Farber Cancer Institute since its 2006 inception

Tata & Howard team members at the Marlborough, MA corporate office participated in the Rally for the Jimmy Fund on April 13, 2015
Tata & Howard team members at the Marlborough, MA corporate office participated in the Rally for the Jimmy Fund on April 13, 2015

MARLBOROUGH, MA, April 14, 2015 – Tata & Howard, Inc., a leading innovator in water, wastewater, stormwater, and hazardous waste engineering solutions, participated in the Rally for the Jimmy Fund yesterday. The Rally encourages people to wear Red Sox gear on Opening Day at Fenway Park, which fell on Monday, April 13 this year, in exchange for a donation to the Jimmy Fund. Tata & Howard team members were happy to donate to the Jimmy Fund while enjoying a casual Red Sox day at the office.

The Rally and the Jimmy Fund

The Red Sox organization has partnered with the Jimmy Fund since 1953, and the Rally for the Jimmy Fund is just one of many Red Sox/Jimmy Fund initiatives. Monies raised through the Rally help ease the patient experience and allow future discoveries to revolutionize cancer treatments around the world. Eighty-nine cents of every dollar raised by the Jimmy Fund and Dana-Farber goes directly to Dana-Farber Cancer Institute, which received the highest possible ranking of four stars by Charity Navigator, America’s largest independent evaluation of non-profit organizations. Since its inception in 2006, Rally for the Jimmy Fund has raised over $4 million.

“We are thrilled to be part of such a worthwhile charity,” stated Donald J. Tata, P.E., President of Tata & Howard.” Through participation in other local events such as the PanMass Challenge and the Mass Dash for the Jimmy Fund, Tata & Howard team members raise funds for the Jimmy Fund throughout the year. The Rally for the Jimmy Fund was yet another way for us to support Dana-Farber and cancer research.”

Separation of Water Distribution System into Two Zones, Spencer, MA

Abstract: The Town of Spencer, Massachusetts received an Administration Consent Order (ACO) from the Massachusetts Department of Environmental Protection (MassDEP) mandating changes to their water treatment process, and the separation of the Town’s water distribution system into two pressure zones. This paper discusses the completion of this project in three phases. The System Study evaluated the conceptual design criteria needed for the two pressure zones and selection of tank sites. The Design Phase highlights permitting and design challenges encountered, and the Construction Phase discusses the overall final product, construction challenges and project successes.