WEF's membership newsletter covers current Federation activities, Member Association news, and items of concern to the water quality field. WEF Highlights is your source for the most up-to-the-minute WEF news and member information.
Treatment Possible: Low-Flow and LEED-Certified
Highway rest stops equipped with low-flow fixtures, geothermal energy, and more
The welcome center’s new wastewater treatment plant (WWTP) — a dual-train pre-engineered sequencing batch reactor (SBR) system — is designed to treat an average daily flow of 38 to 189 m3/d (10,000 to 50,000 gal/d), with a peak flow of 379 m3/d (100,000 gal/d) to account for population increases and greater use of the facilities.
|Designing a wastewater system that meets extreme flow variations and handles high concentrations is hard enough, but when you add in low-flow fixtures, you’ve got a real page-turner for the wastewater enthusiast.
“The real story is the facility,” said Sarah Ridgway, engineering manager at EA Engineering, Science, and Technology Inc. (Hunt Valley, Md.). “It’s designed to meet all the challenges the low-flow fixtures create,” she added.
The state-of-the-art South Mountain Welcome Centers, located on either side of Interstate Highway 70 in Myersville, Md., are heated and cooled by geothermal systems. The design/build project was awarded Silver Leadership in Energy and Environmental Design (LEED) certification in September.
|The South Mountain Welcome Centers incorporate green elements including the enhanced nutrient removal of its dual-train pre-engineered sequencing batch reactor. Photo courtesy of Maryland State Highway Administration (SHA). Click for larger image
“The project was undertaken to achieve a number of goals, such as replacing antiquated existing facilities [and] bring[ing] the wastewater treatment operation into compliance with current regulations,” said James Keseling, project manager with the Maryland State Highway Administration (SHA). “Saving energy was an important goal as well, but not the only goal.”
|The South Mountain Welcome Centers, located on either side of Interstate Highway 70 in Myersville, Md., feature geothermal heating and cooling systems, energy-efficient hand dryers, and low-flow sinks and toilets. Photo courtesy of SHA. Click for larger image.|
High concentrations of nitrogen are “intrinsic to traffic rest areas,” Ridgway said.
South Mountain, with all its amenities — a park-like appearance, walking trails, play equipment, picnic tables, pet areas, drinking fountains, vending machines, single-stream recycling station, and Americans with Disabilities Act-compliant bathrooms with energy-efficient hand dryers and low-flow sinks and toilets — is “a microcosm of a whole city,” Ridgway said.
Restrooms are open 7 days a week, and the combined daily flow ranges from 19 to 72 m3/d (5000 to 19,000 gal/d), which challenged the startup of the dual-train SBR, Ridgway explained.
“Until you’ve got a sludge blanket established, it’s not going to work well,” Ridgway said.
|Traffic over South Mountain ranges from 170,000 to 180,000 vehicles per month during the busy season to about 50,000 vehicles per month during winter. “Thanksgiving 2010 weekend was extremely busy,” Keseling noted. |
The dual-train SBR allows for flexibility to run one or both units, which operate in parallel, to treat flows and provide influent equalization. During higher flows, overflow is sent to a 379-m3 (100,000-gal) lined equalization basin.
At startup, total nitrogen concentrations averaged 185 mg/L — more than double the average influent concentration prior to the upgrade to low-flow fixtures, Ridgway said.
The system removes nitrogen to an average concentration of 6 mg/L — a 97% removal rate.
“That’s pretty impressive removal efficiency, compared to a lagoon system — especially one that’s receiving that concentrated an influent load,” Ridgway said.
|A view of the welcome center’s new wastewater treatment plant — a dual-train pre-engineered sequencing batch reactor system. Photo courtesy of EA Engineering, Science, and Technology Inc. (Hunt Valley, Md.). Click for larger image.|
More than your average SBR
Most rest-stop WWTPs are septic tanks and not designed to denitrify, according to the design engineers. But South Mountain is different.
Denitrification is required to meet total permit goals, “which will eventually become limits,” said Laura Jo Oakes, project engineer at EA.
“The driving force is [that] the facilities were really antiquated,” Keseling said. The previous wastewater treatment systems at the rest stops, installed circa 1970, were unable to treat ammonia–nitrogen sufficiently to meet National Pollutant Discharge Elimination System permit limits.
“It’s more than just the typical SBR system, because it can accomplish [enhanced nutrient removal],” Oakes said.
Nitrogen is eliminated from effluent because the system is designed to release nitrogen as gas. The treatment system recycles water containing nitrates and nitrites from the final settling tank of the reactor back into first-stage aeration. This enables influent biochemical oxygen demand to be the carbon source needed to transform nitrates and nitrites into nitrogen gas.
SHA decided to take advantage of the high-strength influent from the low-flow fixtures to avoid spending money on methanol or other carbon sources for denitrification, Oakes said. The recycling process also enhances biological phosphorus removal, she said.
|An view of the top of the sequencing batch reactor system.The organization expects to recoup its $12.2 million investment in the system through energy savings. Photo courtesy of SHA. Click for larger image. |
The SBR utilizes aspirating reactors, which combine the blower function and pumping in one unit. It is cost-competitive, uses less power — saving money over the long-term — and improves function with its mix of movement and aeration, Ridgway said.
Attaining LEED certification required more than 5% additional investment than a conventional design, Keseling said.
The welcome centers are heated and cooled with closed-loop geothermal technology, each composed of eight wells. Geothermal systems worked well for previous SHA maintenance facility projects and last 30 to 40 years.
|Combined with the energy-efficient lighting, “we plan to save money,” Keseling said. SHA expects to recoup by 2015 its $12.2 million investment in the $22 million project using energy savings. The remaining $9.8 million came from U.S. Federal Highway Transportation Enhancement Program funding. |
Expanded, yet natural benchmark
South Mountain required expansion for increased truck parking, an area for buses and recreational vehicles, and a third parking lot for cars. However, there is more green space — with no irrigation — thanks to native landscaping.
|The expanded parking area. Photo courtesy of SHA. Click for larger image.|
|“It fits in with the environment, which is heavily forested,” Keseling said. |
Pervious asphalt, which allows 102 to 152 mm (4 to 6 in.) of rain per hour to percolate through, completes the picture.
SHA has no plans to replace additional rest areas at this time, but South Mountain, along with its WWTP, could be the future rest-stop template.
According to Ridgway, LEED-certified and ecofriendly water conservative projects require adjusted engineering. “We just have to shift the way we treat if we are going to treat really concentrated loads,” she said.
|An outside view of the wastewater treatment plant. Photo courtesy of EA Engineering. Click for larger image. |
Andrea Fox, WEF Highlights
They Like It. They Really Like It!
NEWater production grows as Singapore prepares to end water imports
At a recent Singapore National Day celebration, 60,000 people packed into the small island-nation’s National Stadium were treated to a free bottle of water which, by all accounts, they drank without complaint.
Is that news? Not ordinarily, but this wasn’t just any bottled water. It was NEWater, Singapore’s own brand of reclaimed water.
While people in many parts of the world may still feel squeamish about drinking freshly treated wastewater, the people of Singapore today “don’t think twice” about consuming NEWater, according to George Madhavan, a spokesman for the Public Utilities Board (PUB), Singapore’s national water agency. Since introducing it in 2002, PUB has bottled and given away more than 20 million bottles at its visitor center and countless community events.
|The goal of the tasting campaign, however, is not to build a consumer market for reclaimed drinking water. “It’s all about education,” Madhavan said.
“We spent years building public acceptance,” Madhavan said. “Our educational campaigns have helped people understand how NEWater is processed and the quality checks that are in place to make sure we’re producing a high-grade product. Now people really understand what it’s about.”
Industrial demand takes priority
Still, the chance that NEWater will be available for sale in Singapore supermarkets any time soon is virtually nil.
|Left from left, PUB's Chief Executive Khoo Teng Chye, Minister of State Amy Khor, and CDL's Group General Manager Chia Ngiang Hong launch PUB’s Water Conservation Awareness Programme 2011. Right, newly inducted Friends of Water at the launch are recognized for educating others and raising awareness about water. Photos courtesy of PUB. Click for larger images.
Most of the 340,650 m3 (90 million gal) of NEWater produced each day is sent directly to factories through a separate NEWater distribution system. There, this NEWater, which represents 30% of Singapore’s total water demand, replaces the potable water that manufacturers formerly used in their processes and cooling systems. A small portion is returned to Singapore’s reservoirs, where it blends with rainwater before entering the conventional drinking water treatment and distribution system.
“NEWater is in high demand at wafer-fabrication plants and other industries that need ultraclean water,” according to Lim Siew Wee, PUB senior manager.
It is easy to see why. PUB’s five NEWater plants make wastewater effluent ultraclean using a three-step purification process that includes microfiltration, reverse osmosis, and ultraviolet treatment. The end product meets drinking water standards set by the World Health Organization, the U.S. Environmental Protection Agency, and Singapore’s National Environment Agency.
It also is affordably priced. “NEWater is both cleaner and priced cheaper than the potable water that industry had been using,” Madhavan said. “So it makes huge sense for them to want all they can get.”
Demand, in fact, currently outweighs supply, even with the 2010 opening of a new 189,000-m3/d (50-mgd) water recycling plant — PUB’s fifth and largest.
The evolution of Singapore’s four-tap strategy
“NEWater has really helped make our water supply sustainable,” Madhavan said.
Fifty years from now, however, the nation’s tap strategy will look much different. With plans in the works to stop importing water, PUB plans to increase NEWater production to meet 40% of the nation’s water demands by 2020 and 50% by 2060, when its final remaining import contract expires. During that same timeframe, use of desalinated water is expected to grow from 10% to 30%.
|Sustainability is a major issue for the island’s 5 million residents, who have long had to rely on unconventional drinking water sources to meet Singapore’s 1.1 million-m3/d (300-mgd) demand. NEWater is one water source in Singapore’s four-tap strategy, Lim explained. In addition to the 30% of water from NEWater, Singapore historically has received as much as 40% of its water supply from Malaysia. PUB “harvests” an additional 20% from local catchments and reservoirs that it has built to capture stormwater. The remaining 10% is produced though desalination.|
|This graphic shows Singapore's water sources in 2011 and expected water sources in 2060. Click for larger image.|
Capping domestic growth
Not only will the proportion of NEWater and desalination grow, but the volume also will have to grow. Fifty years from now, demand is expected to be almost double what it is today, according to Lim.
Much of that demand is expected to come from industry. By 2060, about 70% of Singapore’s water consumption will be for industrial purposes, with only 30% required for domestic needs, Lim said.
To prepare, PUB is using additional outreach programs to raise awareness about Singapore’s water needs and the role both industry and residents play in meeting them.
“We want our citizens to understand not only how we make drinking water from wastewater but also how our water supply cycles down the rivers from one city to the next,” Madhavan said. “This information helps them understand the value of keeping our rivers clean. We believe that if the public values and enjoys our water resources, they will take ownership in helping us protect them.”
PUB has many strategies in place to encourage people to use water wisely, ranging from educational programs to bans on inefficient water devices. It also is working to cap consumer water growth though home water-efficiency programs and what Madhavan calls “a little peer pressure.”
On average, Singapore residents currently consume an average of 154 L of water per person per day, down from 165 L 10 years ago. The target is to reduce the amount to 147 L by the end of this decade.
To help residents, PUB tracks residential monthly water consumption and benchmarks it against averages. “If you live in a four-room flat and use more than 28 m3, you know you have room for improvement,” Madhavan said.
PUB also is doing its part to improve its efficiency. “We are making sure our water network is tight, reducing the amount of water we lose or is unaccounted for in the system,” Madhavan said.
Technology improvements — particularly those related to making desalination more energy-efficient and affordable — also are in the works. The long-term goal is to use “biomimicry” to create a desalination system that copies the function of the human kidney and requires only 20% of the energy needed by the most efficient systems available today. “We hope we’ll be there in the next 30 years,” Madhavan said.
“The beautiful thing about NEWater and desalinated water is that neither is dependent on the weather,” Madhavan said. “We like that these sources are more predictable, so we have more control over our long-term supply.”
Mary Bufe, WEF Highlights
From the President: Introducing WEF’s New Executive Director and Outlining WEF’s Educational Resources
Speaking of WEFTEC, registration opened March 31. For those of you that were at the last WEFTEC held in Los Angeles, you will be pleasantly surprised at the changes that have occurred there. The area surrounding the conference center has been developed from a parking lot into a thriving community with wonderful restaurants and open spaces. It will be a great area to meet your colleagues after a day filled with exceptional technical sessions at the largest annual water quality exhibition in the world.
As many of you know by now, the Water Environment Federation (WEF®; Alexandria, Va.) has a new executive director, Jeff Eger. He joins us after working for 16 years as executive director for Sanitation District (SD)-1 in Northern Kentucky.
Jeff has a wide variety of experience spanning all of the areas in which our membership is involved. Some highlights from his tenure at SD-1 include supervision of the regionalization of 30 municipal sanitary sewer systems, responsibility for the development and implementation of a regional stormwater management program to comply with federal regulations, and negotiation of a unique watershed-based consent decree with state and federal officials — as well as initiation of the design and construction of two new regional wastewater treatment plants.
Jeff will be attending all WEFMAX meetings, so many of you will get to meet him there. You also will have an opportunity to meet him at WEFTEC® in Los Angeles Oct. 15–19. I encourage you to get to know him and learn about his experiences first-hand.
|Jeanette Brown, 2010–2011 WEF President
I would like to note that this year at WEFTEC, there will be several sessions devoted to stormwater and wet weather issues. During the spring, many of us face wet weather issues that affect our treatment plants and collection systems, and stormwater runoff that pollutes our rivers. WEF offers many resources on these problems, both at WEFTEC and on its Web site. The “Access Water Knowledge” section at www.WEF.org has great information available to help you manage these conditions. I encourage you to take advantage of these resources now, available online not only in “Access Water Knowledge” but also throughout the entire Web site.
WEF’s Web site offers additional educational tools and resources. One I am especially excited about is the Distance Learning Program. The program provides online courses for continuing education credits. These courses will help operators, as well as other water professionals, develop the skills and knowledge necessary to perform their duties and develop professionally.
We all face tight budgets and increasing costs and regulations. I hope all of you will take advantage of the programs we offer to help you succeed in your work in protecting our environment.
Jeanette Brown, 2010–2011 WEF President
World Water Monitoring Day Celebrated in 85 Countries
The international education and outreach program World Water Monitoring Day (WWMD) builds public awareness and involvement in protecting water resources by engaging individuals and groups, such as schools and community organizations, in basic monitoring of local waterbodies.
||While officially observed on Sept. 18, WWMD activities took place from March through December last year. WWMD participants sampled their local lakes, streams, rivers, ponds, estuaries, and other waterbodies for the four key water quality indicators of dissolved oxygen, acidity, temperature, and clarity. Some groups also monitored for the presence of macroinvertebrates, which are aquatic organisms that can be used to indicate the health of a waterway, such as dragonflies, mayflies, and scuds.
During WWMD 2010,
- a total of 212,502 participants monitored sites in a range of settings — agricultural, commercial, residential, and industrial — on six continents;
- the number of participants in 2010 increased by 73%, compared to 2009;
- 6325 sites were monitored, with more than half located outside the United States;
- U.S. participants reported data from 2931 sites, the largest number to date; and
- the Water Environment Federation (WEF; Alexandria, Va.) distributed 16,564 WWMD test kits — 51 more than were distributed in 2009.
|Students in Indonesia check dissolved oxygen levels with their World Water Monitoring Day kit. Photo courtesy of Tias Arlianti. Click for larger image.
Participation in WWMD continues to grow, a trend expected to continue during 2011. To find out how to get involved, see www.worldwatermonitoringday.org.
Also in 2010, the first annual Water Champion Award competition was held, and the first “Water Champions” were announced last year. The awardees were honored for their outstanding achievement in increasing awareness of water quality issues through WWMD in 2009.
The coordinators of WWMD, WEF, and the International Water Association (London), received financial and in-kind support for 2010 from the U.S. Geological Survey, the U.S. Environmental Protection Agency, PerkinElmer (Waltham, Mass.), ITT Corp. (White Plains, N.Y.), Sinclair Knight Merz (Sydney, New South Wales, Australia), and Smithfield Foods (Smithfield, Va.).
|Students in Cameroon, Africa, display their World Water Monitoring Day kit. Photo courtesy of Theophile Fonkou.
|Left, a Girl Scout troop in Georgia monitors a local waterway. Photo courtesy of Robert and Mary Rockwood. Right, students monitor the Lena River in Russia. Photo courtesy of Olga Evstifeeva. Click for larger images.|
Grace Woo, WEF Highlights
Tell us what you think of the new WE&T
The September 2010 issue of WE&T marked the launch of the redesigned magazine. We hoped you would like the new format — after all, we based our redesign decisions on reader surveys, emphasizing the most popular sections of the magazine — but also realized that change can be difficult. Sometimes, it takes a while to get used to something new.
So, now about 7 months later, we want to know what you think. Your honest opinions, both good and bad, will help us continue to make improvements that better serve our readers.
Tell us, what do you think about the redesigned WE&T? Take the brief survey.