Unidirectional flushing (UDF) is a unique process utilized to maintain a distribution system as well as learn critical information about the system. An effective UDF program should be conducted annually, at a minimum. Check out our UDF infographic that shows the benefits of UDF over conventional flushing:
Please feel free to print and share, with attribution, our UDF Infographic. A high resolution pdf can be downloaded by clicking here.
Stormwater runoff is a concern year-round, but even more so in the spring when snow is melting and rain is abundant, particularly in humid continental climates. Stormwater starts as precipitation such as snow, sleet, and rain, which lands on natural ground cover such as forests, grass, or gardens. In a natural environment, stormwater soaks into the ground and is filtered by layers of dirt and rock, then finds its way to our groundwater and drinking water supply. Due to urbanization, stormwater in developed areas does not land on natural ground cover but instead washes off roads, driveways, parking lots, rooftops, and other impervious surfaces, becoming stormwater runoff. Stormwater runoff picks up road salt, chemicals, oil, bacteria, sewage, sediment, and garbage, then washes these pollutants into ditches and storm drains, contaminating our streams, rivers, ponds, and lakes. To make matters worse, climate change exacerbates stormwater runoff and contributes greatly to the impairment of surface water supplies.
A study by scientists from the National Center for Atmospheric Research in Boulder, Colorado published in December 2016 indicates that climate change will likely bring more intense, frequent, damaging storms to all areas of the country, particularly to the Northeast and the Gulf Coast. In fact, studies show that storms in these areas could become up to five times as frequent and bring 70% more rain if greenhouse gas emissions are not reduced. Storms of this magnitude will likely cause flash floods, landslides, and an overabundance of stormwater runoff – far more than current municipal stormwater systems are designed to handle.
The study also indicated that regions such as the Pacific Northwest and central United States will likely become drier, but with more intense, extreme rainfall. We have already seen this in northern California, where the Oroville Dam suffered serious damage after drenching rains in February. Prior to these rains, the state had been plagued by severe drought. Rising temperatures increase atmospheric humidity, causing extreme precipitation and an increased risk of flash flooding. And while it may seem counterintuitive, drought only intensifies the problem. Drought leads to less vegetation and more firmly packed soil, both of which inhibit infiltration. When heavy rains follow drought, soil tends to erode, washing remaining plants away as well. Regular, gentle rain is the key to restoring soil, and without it, soil degradation will only intensify.
Unfortunately, the above-mentioned factors will likely lead to an increase in stormwater runoff and its accompanying problems. Municipal stormwater systems, already faced with increased nutrient regulations, will likely become overwhelmed, resulting in backups, localized flooding, and increased runoff of contaminants such as bacteria and nutrients into waterways. Also, combined stormwater and wastewater systems overwhelmed by extreme precipitation will release more combined sewer overflows (CSOs) into our rivers, lakes, and streams, degrading water quality and affecting aquatic life. At the same time, drought exacerbates the problem by lowering water levels, leading to more concentrated levels of pollutants in our waterways. These combined factors cause water quality deterioration and create major problems for water treatment plants. Already facing dwindling budgets, municipalities will have difficulty meeting water quality standards if stormwater runoff continues to increase unabated.
Fortunately, successfully managing stormwater runoff is a realistic goal with proper planning and incorporation of best management practices (BMPs). Systems that proactively develop strategies to address stormwater runoff will find themselves far better prepared to manage both increased stormwater and more stringent regulations. Stormwater management strategies include the following:
Increase the use of Low Impact Development. Low Impact Development (LID), also known as green infrastructure, is a stormwater management approach that maintains natural hydrology during site development. LID minimizes impervious surfaces and utilizes existing natural site features along with conservational controls to manage stormwater. Examples of LID design include bioretention basins, grassed swales, and rain gardens.
Landscape with native flora. Native trees and plants provide habitat for and attract birds, butterflies, and other beneficial local wildlife, and are acclimated to local rainfall amounts and climate. Unlike turf grass, native plants require very little maintenance because they are naturally resistant to local pests and disease. Because they do not need fertilizers, pesticides, or supplemental watering, they are easy and inexpensive to maintain and are environmentally friendly.
Climate change and stormwater runoff together create the perfect storm for water quality degradation. We are already seeing the effects of climate change on our nation’s infrastructure, and unless we address these complications now, we will likely find ourselves increasingly burdened by boil water orders and expensive water treatment projects. Fortunately, by proactively making some simple and largely inexpensive environmental improvements, we can protect our nation’s water bodies for future generations.
March 19-25 is Fix a Leak Week 2017.
Fix a Leak Week is celebrated in March of each year as a time to remind Americans to check their household fixtures and irrigation systems for leaks. In addition, it is a good time to address the leaks that we cannot see — those in our underground infrastructure. By addressing leaks in our homes and in our water systems, we can help to save our world’s most precious resource.
A good method to check for leaks is to examine your winter water usage. It’s likely that a family of four has a serious leak problem if its winter water use exceeds 12,000 gallons per month.
A leaky faucet that drips at the rate of one drip per second can waste more than 3,000 gallons per year. That’s the amount of water needed to take more than 180 showers!
An irrigation system should be checked each spring before use to make sure it was not damaged by frost or freezing.If you find any of these leaks, and need assistance on how to fix them, visit the EPA’s “Fixing Leaks at Home” page.
About 20% of our nation’s drinking water is “lost” before it reaches the consumer, amounting to about seven billion gallons of clean, treated water lost in this way every day. Also called non-revenue water, this lost water would be enough to supply the ten largest cities in the United States for a full year. It also accounts for billions of dollars in lost revenue each year – funds that utilities desperately need to keep their systems running smoothly and safely. Most of this non-revenue water is the result of our nation’s leaking, aging pipes, which received a grade of D on the American Society for Civil Engineers (ASCE) 2017 Report Card.
Feel free to share the above infographic (with attribution), download a printable PDF, or request a printed poster.
During Fix a Leak Week, while we focus on leaks and repairs in our homes, let’s also give attention to our nation’s crumbling infrastructure. Through careful management and capital planning, efficient use of infrastructure budgets, and increased infrastructure funding, we can assure we have a sufficient, safe, sustainable water supply for generations to come.
www.epa.gov
Modern-day, developed nations use an exorbitant amount of chemicals for a variety of reasons. Some of these chemicals are used to prevent and treat illness, to reduce pain from injury or surgery, to treat mental health issues, and for hygiene, grooming, and cosmetic reasons. Commonly referred to as Pharmaceutical and Personal Care Products, or PPCPs, these products include prescription and over-the-counter medications, cosmetics, fragrances, face and body washes, sunscreens, insect repellants, and lotions.
In addition to PPCPs are endocrine disrupting compounds (EDCs). The endocrine system is an intricate network of glands including the thyroid, pituitary, adrenal, pancreas, thymus, and reproductive organs that release precise amounts of hormones into the bloodstream in order to regulate essential biological functions in humans and animals such as growth, development, reproduction, and metabolism. EDCs are any external natural or synthetic compounds capable of interfering with the body’s endocrine system by disrupting the synthesis, secretion, transport, bonding, or elimination of natural bodily hormones.
Effects of PPCPs and EDCs in Water
PPCPs and EDCs enter our waterways through sewage, leachate from landfills and septic systems, flushing of unused medications, and agricultural runoff, and they have the potential to cause a myriad of problems. While there has not yet been a truly significant amount of research completed on all of these products and chemicals, some facts are known. For example, excessive antibiotic use has led to the development of “superbugs,” or bacteria such as MRSA that are resistant to most antibiotics. Methadone reacts with chloramine, a chemical used to treat drinking water, to form N-nitrosodimethylamine (NDMA), a known carcinogen. EDCs interfere with the endocrine system, potentially causing reproductive, developmental, neurological, and immunologic problems in both humans and wildlife.
Some of the most common EDCs in drinking water include estrogen and progesterone from birth control pills, as well as anabolic steroids. These compounds interfere with the reproductive capabilities of aquatic wildlife. Examples include eggshell thinning and subsequent reproductive failure of waterfowl; reduced populations of Baltic seals due to lower fertility and increased miscarriage; development of male reproductive organs in female marine animals, such as snails; feminization and subsequent decreased populations of certain types of fish, including bass; and reduced or malformed frog populations.
Regulating PPCPs and EDCs in Drinking Water
Currently, most PPCPs and EDCs are not regulated at either the state or federal level; however, they are being investigated by the Environmental Protection Agency (EPA) as Contaminants of Emerging Concern. Because PPCPs and EDCs appear to hinder reproduction in marine life, many state environmental organizations strongly support additional research and potential regulation on these compounds. In 2006, Massachusetts became the first state in the nation to set drinking water and cleanup standards for the known EDC perchlorate after it had been detected in the state’s drinking water, and many states have implemented public education campaigns on these compounds, their effects, and their proper disposal.
Treating PPCPs and EDCs in Drinking Water
Currently, there are no treatment processes specifically designed to remove PPCPs or EDCs from drinking water; however, research is currently underway at the national level to determine the effectiveness of existing drinking water treatment technologies, such as chlorination, carbon filtration, and ozonation, on the removal of PPCPs and EDCs. In addition, several new, innovative technologies that specifically target PPCPs and EDCs for removal have shown promise. One example utilizes a catalyst called TAML(r), which is iron plus tetra-amido macrocyclic ligand, to remove PPCPs and EDCs from wastewater, while another utilizes zeolite adsorption to remove PPCPs and EDCs from water.
How We All Can Help Reduce PPCPs and EDCs in the Environment
On an individual level, taking small, simple steps can have a large impact on the amount of PPCPs and EDCs in our water supply:
In Conclusion
The problem of PPCPs and EDCs in drinking water does not appear to be going away any time soon. In order to mitigate damage caused to both humanity and the environment, additional research and focus must be placed on these compounds. It is imperative that we implement additional regulations, engineer innovative and cost-effective treatment technologies, increase funding to upgrade infrastructure, and reduce our personal contributions of PPCPs and EDCs to the environment.
National Groundwater Awareness Week is an annual occurrence sponsored by the National Ground Water Association (NGWA). During National Groundwater Awareness Week, NGWA aims to educate the public on the importance of groundwater and of preserving this precious resource. Many companies in the water industry, including Tata & Howard, support NGWA to help spread the word about groundwater.
All About Groundwater
Life as we know it would be impossible without groundwater, or the water that fills cracks, voids, and other openings in soil, sand, and bedrock. About 99% of the available freshwater on Earth is groundwater. Because of this, it is the world’s most extracted natural resource, at the rate of about 259 trillion gallons per year, with about 60% of that withdrawal going towards agriculture. Groundwater also supports our world’s ecosystems. People with wells use groundwater for drinking water, and most groundwater flows directly into streams, rivers, and lakes from beneath.
Do Your Part!
If you own a private water well, have your water tested annually or if there is a change in the odor, taste, or smell.In Conclusion
Groundwater is essential to human life and a healthy environment. Not only is it imperative that we protect groundwater from contamination by chemicals and waste, but it is also important to remember to conserve water wherever we can. Groundwater sources are being withdrawn at a faster rate than they are being replenished, and we cannot continue to utilize our world’s most precious resource with such abandon. Help NGWA spread the word during National Groundwater Awareness Week to ensure we all remember to do our part.
This week is Engineers Week, which is celebrated in February of each year, and Introduce a Girl to Engineering Day always falls during Engineers Week. Introduce a Girl to Engineering Day 2017 fell on February 23 this year, and since “Girl Day” is very important to Tata & Howard, we decided to celebrate the day by inviting local middle school girls to come into the office for a special event. The evening was a great success – and also quite a bit of fun!
In the engineering industry, only 11% of the workforce are women. However, Tata & Howard has always been above this statistic and since the beginning, has striven to recognize the value of women in engineering. Tata & Howard was established in 1992 by Donald Tata, P.E. and Paul Howard, P.E. Initially a two-person firm, the company quickly grew, and out of the first 20 hires, eight were female. This trend continued, and today, 32% of our engineering workforce is female, including the firm’s two co-presidents, Karen Gracey, P.E. and Jenna Rzasa, P.E.
To celebrate our commitment to women in engineering, Tata & Howard hosted an Introduce a Girl to Engineering Day event for local middle school girls at our corporate office in Marlborough, Massachusetts. All of our Marlborough-based female engineers participated with the exception of Maya Rhinehart, who was instead volunteering at Girls Inc. The overwhelming participation of our female engineers exemplifies their commitment to the industry as well as their incredible sense of teamwork and philanthropy.
The evening started with a brief introduction given by Karen, including a story of her experience at the University of Vermont, where she was sometimes the only female in her engineering classes. Justine Carroll, P.E., Project Manager and Team Leader, then presented a slideshow on environmental engineering and talked about the services provided by Tata & Howard, after which the female engineers each shared their personal journeys to choosing the engineering field. The girls then enjoyed a dinner of pizza and salad during which Amanda Cavaliere, Project Manager and Team Leader, led a discussion on the value of great teachers.
Once dinner was finished, the girls participated in a water tank building activity with some of our female engineers. Each group was given supplies including a disposable cup, rubber bands, chewing gum, string, drinking straws, paper clips, push pins, and Band-Aids and were charged with building the tallest elevated “tank” that could successfully hold eight ounces of water for 30 seconds. For 30 minutes, the girls brainstormed and built alongside the engineers until their masterpieces were finished. Immediately after, the tanks were tested for their structural stability. Karen poured the water into each of the “tanks” and we started the timer. Unfortunately, neither tank successfully lasted for 30 seconds, but we assured the girls that even engineers who attempted this activity at local trade organizations were unsuccessful. After all – Band-aids and chewing gum are no substitute for concrete and steel! One thing is for sure: there were plenty of laughs during the testing portion of the event.
Each girl was sent home with a certificate of completion and many smiles. The event was a huge success for not only the young girls, but also for the employee-owners who participated, and we are already planning for next year’s Girl Day. How did you celebrate Girl Day or E-Week? Let us know in the comments below – and Happy Engineers Week!
Dams are an integral part of modern day infrastructure, providing many benefits to society. Yet dams have also come under scrutiny in the past few years as they can potentially have a negative effect on an area’s ecology. Some people, including environmental groups, are vehemently calling for the removal of many dams, while others continue to promote the positive impact that dams have on our culture. To remove or not to remove? That is the question.
The Benefits of Dams
Dams have been in existence for over 5,000 years. The first known dam to be built was the Jawa Dam, which was constructed around 3,000 BCE in Mesopotamia. Since that time, dam engineering has progressed significantly, and there are now about 50,000 large dams in use worldwide. The United States currently has 87,000 dams over six feet in height, 2,000,000 dams in total, and 50 major dams — the most in the world. And though they may have an ecological impact, dams admittedly provide myriad benefits, both economically and socially.
Recreation
The most prevalent function of America’s dams is to provide recreation. Families flock to our nation’s lakes that are created by dams for vacations and downtime to enjoy boating, camping, picnic areas, water skiing, fishing, and water sports. Some of the most beautiful and enjoyable vacation spots in the nation are lakes created by dams. In fact, of the top ten most popular vacation lakes in the United States, eight are impounded by dams, including number one on the list, Lake Tahoe. These recreational areas bring in millions of dollars of tourist funds and are important to the economic health of the nation.
Flood Control
Flood control dams impound floodwater to help prevent loss of life and protect property caused by flooding. They also protect farmers’ crops from being destroyed by flood inundation. Protecting people, property, and crops also provides high economic benefit.
Water Storage (Fire & Farm Ponds)
While major dams create massive lakes, thousands of other dams create smaller reservoirs throughout the nation that supply water for industrial, municipal, and agricultural uses. Water from these human-made lakes supply water for livestock and fire protection for cities and towns, as well as industrial uses.
Irrigation
Over ten percent of American crops are irrigated using water impounded by dams. This irrigated farmland provides thousands of jobs to hardworking American people, providing huge economic benefit to our nation.
Mine Tailings
Mine tailings are sometimes overlooked as dams, but there are actually over 1,300 mine tailings impoundments in the United States. The tailings allow for the mining and processing of coal and other minerals while protecting the surrounding environment.
Electrical Generation
While only 2.9% of our nation’s dams provide hydroelectric power, they account for over 35% of our nation’s renewable energy, over 6% of our total electricity, and around 10% of our nation’s total power needs. In fact, the United States is the second largest producer of hydropower in the world, second only to Canada. Hydropower is considered a clean energy source because it does not contribute to air pollution, climate change, or ozone depletion.
Some other uses for dams include debris control and navigation.
Negative Effects of Dams
While our nation’s dams provide many benefits, they also cause many concerns. First, the cost of maintenance sometimes outweighs any positive impact the dam may provide. In addition, dams can also have a negative effect on the environment, and some pose serious hazard to people and property. By 2020, about 70% of our nation’s dams will be over 50 years old and will require significant rehabilitation and repair. In fact, the Association of State Dam Safety Officials has estimated that it could cost over $51 billion to rehabilitate our nation’s non-federally owned dams. Therefore, it is imperative that we consider all aspects of dams and their environmental, economic, and social impact before making any rehabilitation decisions.
Many dams continue to provide benefit to our nation and its communities, while others have simply outlived their useful function. In these cases, it makes sense to remove them rather than to pour increasingly dwindling funds into their repair. Since 1912, over 1,300 American dams have been removed, 62 of these being removed in 2015 alone.
Maintenance vs. Removal
Like all infrastructure, dams require routine and ongoing maintenance to keep them safe and functioning. Frequently, dams are allowed to deteriorate until they pose a threat to public safety, particularly when they have fallen out of usage. In these cases, it is prudent for dam owners to work with state and federal dam experts to determine whether it makes sense to simply remove the dam rather than repair it.
Environmental Impact
One of the most significant impacts that dams have on the environment is interference with migratory fish such as salmon. Dams block the migration of these fish to upstream spawning areas, while also limiting the movement of both sediment and woody debris necessary to the maintenance of downstream spawning grounds. Many environmental activists call for the removal of dams that interfere with fish spawn, citing disruption of local ecology. The good news is that once a dam is removed, species quickly return to their upstream spawning areas, regardless of the length of time that the dam has been in place.
Tourism
While dams provide significant recreational benefits, in some cases they can also hinder them. When a river is returned to its free-flowing state by dam removal, new recreational opportunities arise, including whitewater rafting, kayaking, and fly fishing. These activities can greatly benefit local economies by increasing tourism to these typically remote communities. Also, removing dams can increase the number of recreational and commercial fish species such as trout and salmon. Both commercial fisheries and recreational fishermen benefit from increased catch rates though additional revenue and increased tourism, respectively.
Decreased Cost-Effectiveness
Many aging dams were originally built to supply hydro power to nearby industrial facilities such as mills and factories, and they generate little electricity. Because the nation has shifted away from local power supply to a more regional production, the power generated by these older dams is expensive and, since many of the older factories and mills have permanently shut down, are oftentimes no longer even needed.
Cultural Implications
Many Native American populations place significant spiritual and cultural value on free-flowing rivers and the natural ecology, as evidenced by the long standoff between the federal government and the Standing Rock Sioux tribe. Because dams change the natural ecology and prohibit the free flow of rivers and waters, Native American tribes often view them in a negative light.
Property Value
Dams have the tendency to drive down property values, particularly smaller dams which are no longer used for their original purpose. These dams can present flood risk as well as lower water quality, and removal of these dams improves property values.
In Conclusion
The question remains: to remove or not to remove? The reality is that there is no easy or right answer. The decision on whether to repair or remove a dam is complex, and all contributing factors must be considered carefully before determining the best course of action. The decision must include weighing the current value of the dam, including its social and economic benefits, against the costs of upkeep and the detrimental effects of the dam on the environment. When the dam has little social or economic effect either way, the long-term costs of maintenance versus the cost of removal must be considered.
Thousands of American dams have aged to the point that they require significant repair, while scientific understanding of our world’s delicate ecology and has grown exponentially. Also, advances in economic methodology has highlighted the positive impact that dam removal can have on local and regional communities. Because of these modern-day shifts, it is often considered prudent to remove dams that no longer properly serve their original purpose. At the same time, dams that still function and provide important benefits such as irrigation and flood control are often repaired and maintained. The fact remains that the answer is not clear or definitive. All aspects of a dam, its location, original use, state of repair, social and cultural implications, and surrounding environment must be considered prior to determining the best course of action.
Introduction
New England is one of the oldest and most historically rich areas of the nation. Famous events such as the pilgrims founding Plimouth Plantation and Paul Revere’s midnight ride took place in Massachusetts. New Hampshire planted the first potato in America, Maine introduced the nation’s first sawmill, and Vermont produced the nation’s first gummed postage stamp. Connecticut has the most “firsts” of any state in the nation including the first newspaper, submarine, and hamburger, while tiny but mighty Rhode Island was the first colony in the nation to declare independence from Britain. New England also boasts another first: it is home to the nation’s first water distribution systems.
A Brief History
Boston, Massachusetts became home to the nation’s first waterworks in 1652. Distribution pipes at that time were made of wood, constructed from bored-out logs from the area’s plentiful hemlock and elm trees and attached together with pitch, tar, or iron hoops. While this rudimentary distribution system did supply some of the area’s residents, it was mainly used for fire protection as homes during that time — constructed of wood and heated with fireplaces —were particularly prone to fire.
It was over a century before other New England cities began installing wooden distribution pipes. Providence, Rhode Island, Portsmouth, New Hampshire, and Worcester, Massachusetts all laid wooden pipes during the late 1700s, and several other cities followed suit in the early 1800s. Contrary to some urban myths, wooden pipes are not still in use in any areas of New England today. The high pressure from modern water systems would instantly split any existing wooden pipes. Wooden pipes that are occasionally unearthed during some construction projects were disconnected years ago.
Wooden pipes were problematic for many reasons including warping and sagging, insect infestation, rotting, taste issues, and splitting. As iron became increasingly available during the early 1800s, cities began installing iron pipes. The first iron pipes in New England were installed in Portland, Maine in 1812, followed by Montpelier, Vermont in 1820, and in both instances the pipes were lead. Many other cities followed suit throughout the 19th century, utilizing wrought iron, cast iron, and lead pipe. In the 1950s, ductile iron piping was introduced and boasted the longevity of cast iron with the addition of increased strength, flexibility, and safety. It became widely used in the 1970s and it is still the material of choice throughout New England today.
Distribution Systems Today
New England can be considered a pioneer of our nation’s water infrastructure. After all, distribution systems have grown from a few wooden pipes in Boston to the intricate, complicated underground infrastructure that we enjoy today. However, because much of the area’s infrastructure was laid so long ago, it has reached the end of its useful life. Water main breaks occur daily and are not only inconvenient to customers, they can also be dangerous, as evidenced by the November 2016 water main break in Boston, Massachusetts that caused manhole fires and forced evacuation of the area. Maintaining and updating our distribution systems is critical to the health and safety of our nation, its people, and the economy. But with limited budgets and resources, where do we start?
Strategically prioritizing improvements is imperative to today’s water systems, as the rehabilitation and replacement of our nation’s buried infrastructure is an ongoing task. Asset management provides a roadmap for utilities, allowing them to maximize their limited infrastructure dollars by planning for the replacement of critical infrastructure over time. Tata & Howard’s Capital Efficiency Plan™ (CEP) methodology takes it one step further by combining the concepts of asset management, hydraulic modeling, and system criticality into a single comprehensive report. The final report provides utilities with a database and Geographic Information System (GIS) representation for each pipe segment within their underground piping system, prioritizes water distribution system piping improvements, and provides estimated costs for water main replacement and rehabilitation.
Since the firm’s inception in 1992, Tata & Howard has remained a niche firm with deep experience and expertise in the water environment, and has provided CEP and hydraulic modeling services for countless municipalities throughout New England. Tata & Howard has one of the largest pipe asset management databases of any consulting engineering firm in New England. In fact, we have data on over 5,000 miles of New England pipe, providing utilities with critical information about their systems such as condition and probability of failure of certain pipe cohorts.
In Conclusion
Water distribution systems have come a long way since the days of hollowed out logs providing fire protection to colonial Bostonians. The underground network of distribution pipes has grown astronomically and now incorporates safer, stronger, and more cost-effective materials. As distribution systems are updated and expanded, it is critical that accurate, up-to-date information is available to water systems so that they may invest their limited capital wisely.
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.
Health Effects of Manganese
Manganese 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
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 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
For 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
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.
“Coming together is a beginning. Keeping together is progress. Working together is success.” —Henry Ford
Friday, January 27 is National Fun at Work Day (not to be confused with International Fun at Work Day, which falls on April 1). Because teamwork is one of our core values and we are a 100% employee-owned company, we take teambuilding and fun…seriously? That seems like a bit of an oxymoron, but put it this way – we like to have a good time together!
Tata & Howard celebrated National Fun at Work Day by planning a summer barbecue in January, complete with summer fare, outdoor (but indoor) games, and casual attire. To start the festivities in our corporate office in Marlborough, Massachusetts, we fired up the gas grills in the parking lot and cooked burgers, including beef, turkey, and veggie. While it was a little chilly and windy outside, there was no rain or snow, and the smell of grilled food was certainly reminiscent of a warm summer day. EOs contributed by bringing in their favorite summer barbecue dishes, including pulled chicken, slow-cooked ribs, pasta salad, chips, and dips. Even the desserts were summer-themed – popsicles and ice cream cake, in addition to cookies and brownies. Once EOs finished up their lunches, they participated in some outdoor games – inside! Steve Landry once again showed his gaming expertise by capturing the title of cornhole champion, while Karen Gracey learned how to play Lawn Yahtzee for the first time. Phil MacClellan, a seasoned dice expert, scored the day’s only Yahtzee.
At our Waterbury, Connecticut office, EOs agreed that the big food hit of the day was Dave Lombardo’s delicious pulled pork. Other offerings included baked beans, chicken wings, potato salad, cole slaw, cornbread, and donuts. Showing innovation even during fun activities, Waterbury EOs decided to create their own office version of cornhole using empty boxes of various sizes and plan paper weights. Nobody is quite sure who won, except that it definitely wasn’t Steve Rupar – he may want to stick to water audits!
Maine may be known for its brutal winters, but that didn’t deter our Portland, Maine EOs from braving the elements to have an outdoor barbecue. Dan Bishop manned the grill and cooked hot dogs, sausages, and burgers, and team members joined him outside for some fresh air and camaraderie. Other fare included homemade pickles, dips, and veggie offerings. Paul Cote even wore his favorite Hawaiian shirt to add some extra summer flare.
During our Fun at Work Day activities, there were a lot of smiles and laughs, and afterwards we all went back to work feeling refreshed – and quite full! EOs overwhelmingly agreed that the day’s activities were very fun, and we all enjoyed spending some quality downtime together. Did your team participate in Fun at Work Day? We’d love to hear how you celebrated!