SURE! Sustainable Utilities Research and Education

SURE! is a program within the Cal Poly School of Civil and Environmental Engineering that seeks to find solutions within the water-energy nexus that will provide sustainable solutions to wastewater recycling and resource recovery. The mission of the SURE! program is to help expand the wastewater recycling workforce and develop new sustainable technologies. The program received a WEF award for its commitment to water treatment education and research. The SURE team has worked on algae-based wastewater treatment, algae biofuels, conversion of wastewater solids to energy, potable re-use, and dairy wastewater treatment. 

Decentralized Wastewater Infrastructure Challenges in the Alabama Black Belt

A quarter of Americans rely on decentralized wastewater systems, including septic tanks, because they are too far away from municipal sewers or the local environment cannot support a wastewater treatment plant.

Decentralized wastewater treatment facilities can offer economic and environmental benefits to a community, but they can also be dangerous to public health and the local ecosystem if they are not designed properly.

In the Black Belt region of Central Alabama, the rural landscape and heavy clay soils make it difficult to establish a traditional wastewater facility. These communities have struggled with wastewater management for years and the U.S. EPA (with many partners) has been working to help develop long-term solutions.

Impermeable soil, high rates of poverty, and no sewer access can result in difficult choices. Some communities in this region use straight pipes to carry wastewater to a nearby location like a ditch or woods, where residents can then be exposed to raw sewage.

Decentralized wastewater treatment systems can use a variety of different approaches to process a community’s wastewater, but there are also financial and managerial solutions that can be explored. Responsibilities can be better distributed and organized with community leadership. Individuals who attend community meetings and communicate with their state and local government officials are more likely to have their voice heard. 

The newly passed infrastructure bill is set to contribute $150 million in decentralized household grants over five years to help low-income homeowners construct or repair failing septic systems. Investments are also needed in cost-effective treatment technologies and innovative approaches to help municipal wastewater systems reach rural communities. 

Dig Deep, an organization that helps bring running water and adequate sanitation to communities across the United States, created a decentralized wastewater innovation cohort to help connect rural communities with innovative solutions. 

The Alabama Black Belt is just one of many regions of the United States that are struggling, with a history of environmental injustice compounding logistical challenges. Roughly 2.2 million Americans across the United States still do not have running water or adequate sanitation. 

The information in this blog post was presented at a U.S. EPA webinar in May 2021. A recording is available to explore this topic in more depth:

Are Solar Powered Water Treatment Plants the Future?

Clean water and clean energy are both essential on the road to a more sustainable future. To be able to tackle two issues at once and provide clean water using clean energy is exactly the kind of innovation that the world needs. A few wastewater treatment plants across the country are taking matters into their own hands and converting their plants to solar-powered energy. 

The solar farm for the Wastewater Treatment Plant in New Stanton was just finished. The Federalsburg Wastewater Treatment Plant just received over one million dollars in grant funding for the construction of a solar panel system. The city of Danbury, Connecticut is also considering a solar installation that would power their city’s wastewater treatment plant. The Diablo Water District also installed a solar power system in their facility to help them achieve their ambitious goal of being carbon neutral by 2027.

Powering water treatment plants with solar power helps the environment and it can help facilities save money because it can lock in electrical rates. It also makes facilities more resilient to power outages from natural disasters or other power grid failures. Utilities that convert their water treatment facility to solar power help their community and country work towards achieving the renewable energy goals the world is striving towards. 

Elevating Women in Water

Contributed by Margaret Golden

Women make up over half of the population, but account for less than 20% of workers in the water industry. The work that women contribute to the water industry is necessary and important, offering valuable insight to bring the industry into the future.

With a new generation of workers on the rise, it is important that women feel empowered to work in the water. Brianna Huber, chemist with the City of East Moline, is on a mission to not only recruit women into the industry but see equity in their opportunities. Her non-profit, Her2O, is currently seeking members who are ready to forge lasting change.

Women across the country are already making great impacts, breaking glass ceilings and blazing their path to the top of the water world. Two leaders in the water industry recently discussed what it means to them to be a woman in the water industry.

Newsha Ajami, the Director of Urban Water Policy at Water in the West at Stanford University, discussed in a podcast what we need to do to transition to 21st century sustainable water management. Michelle Harrison talked about her favorite parts about working as a wastewater treatment operator at the Northwestern Water & Sewer District.

Many organizations take the time to specifically acknowledge the women in their work place during women's history month. Last spring the U.S. EPA highlighted Sandhya Parshionikar, Director of the Water Infrastructure Division, Center for Environmental Solutions and Emergency Response. Rural Communities Assistant Partnership highlighted Ines Polonius, CEO of Communities Unlimited.

Cuyamaca College in El Cajon also hosts an annual symposium dedicated to Women in Water.

Wastewater Collection System Components

Contributed by Phil Vela

A wastewater collection system is a series of pipes, tunnels, conduits and other devices that transport wastewater from homes, businesses and industries to a central treatment plant. Transport of the wastewater is either by gravity (the preferred method) or with the use sanitary lift or pump stations to either a location that gravity can be used or to another lift or pump station and finally to the wastewater treatment plant. In either case, the collection system has many functioning parts as shown and described below.

Figure 1 (source) shows the different types and sizes of sewer lines in a typical wastewater collection system. They range from the smallest (approximately 4 inches) located at the home or business to the large truck mains (minimum 12 inches and can be as large as 27 ft tunnels in large cities) that carry the sewerage to the waste treatment plant. A brief description of each follows.

Here's house the Louisville Metropolitan Sewer District describes each of the components:

House Sewer conveys the sewerage from a building to the lateral or branch lines.

Lateral & Branch Sewers are the upper ends of the municipal sewer system. Laterals dead-end at their upstream end with branch sewers collecting the wastewater from several lateral sewer lines.

Sub-main Sewers are collectors for numerous lateral and branch sewers from an area of several hundred acres or a specific neighborhood or housing development They convey the wastewater to larger trunk sewer lines, to lift stations or to a neighborhood package water quality treatment center.

Trunk/Main Sewers serve as the main arteries of the wastewater collection system. They collect and convey the wastewater from numerous main sewer lines either to a water quality treatment center or to a interceptor sewer.

Interceptor Sewers receive the wastewater numerous from trunk sewers and convey it to a water quality treatment center. These are the largest diameter lines in the sewer system and the furthest downstream in the system.

Lift or Pump Stations are utilized in gravity sewer systems to lift (pump) wastewater to a higher elevation when the route followed by a gravity sewer would require the sewer to be laid at an insufficient slope or at an impractical depth. Lift stations vary in size and type depending upon the quantity of wastewater to be handled and the height it must be lifted.

This video from American Water College describes the components of a wastewater collection system:

Using Willow Trees to Treat Wastewater

This article was featured in a recent edition of Innovations for Small Systems, our monthly water technology newsletter.

Researchers at University of Montreal, Canada have found a way to filter the waste from municipal wastewater through the roots of willow trees while also producing renewable bioenergy and 'green' chemicals. The study, which was published in Science of the Total Environment, details the experiment conducted in Quebec, Canada to investigate the potential for sustainable wastewater treatment through phytofiltration, an emerging method to remove contaminants from water through the use of plants, to be integrated with renewable biorefinery. 

Phytofiltration plantation is an alternative wastewater treatment method where root systems from non-food crops, such as fast-growing trees, are used to capture contaminants and nutrients from wastewater. Short rotation coppice (SRC) willow has been considered as a promising renewable bioenergy crop due to its natural tolerance to contamination and the roots ability to filter out nitrogen in sewage, which can then be harvested for renewable lignocellulosic biofuels. This concept of a biorefinery illustrate the potential of multifunctional biotechnologies to address environmental challenges caused by human activities.

Photo Credit: Katy Walters

Studies Track PFAS Through Wastewater Facilities

This article was featured in a recent edition of Innovations for Small Systems, our monthly water technology newsletter.

University of New Hampshire (UNH) researchers have conducted two of the first studies in New England to show that per- and polyfluoroalkyl substances (PFAS) are ending up in the environment differently after being processed through wastewater treatment facilities, making it more challenging to set acceptable screening levels.

Researchers including Paula Mouser, associate professor of civil and environment engineering at UNH, aimed to highlight the gaps around contaminants of emerging concerns (CECs) in wastewater residuals and to stress that more research is needed to assess the impact of facility design and operation on the treatment of CECs before costly upgrades are implemented to comply with stricter drinking water standards. 

The first study, which was recently published in The Royal Society of Chemistry, investigated the distribution and fate of 24 different PFAS through six New Hampshire wastewater treatment facilities to examine how they are distributed after being treated. The study aimed to characterize PFAS in wastewater treatment influent, sludge, and effluent discharging into the Great Bay Estuary in southeastern New Hampshire. 

The second study, which was featured in the New England Water Environment Association Journal, evaluated the changes in 24 PFAS and 21 pharmaceutical and personal care products (PPCPs) during wastewater treatment and assessed the composition of PFAS in biosolids post-stabilization treatment. Recent studies have suggested PPCPs and PFAS from land-applied biosolids may accumulate in soils, agricultural crops, and food products. This study compares the composition and concentration of PFAS from 39 biosolid samples collected from WWTFs in New Hampshire and Vermont.

Photo Credit: Conservation Law Foundation

Free Wastewater Quizzes

Last year the much-loved Skills Builder tool from WEF, the Water Environment Federation, received an refresh along with a commitment to keep it updated.

The WEF Skills Builder offers randomized 10-question quizzes on wastewater and laboratory topics at three difficulty levels. The updates modernized the functionality as well as aligned the questions with ABC's standards for subject matter and format.

The tool is free to use and correct answers are provided, along with linked references to WEF's publication store.

Study guides and test preparation resources are a popular topic on our blog, including this post on studying for certification exams.

Fatbergs, the Icebergs of a Wastewater Collection System

Contributed by Phil Vela

The term fatberg was first used in 2008 to describe the "large, rock-like lumps of cooking fat" washing up on beaches in Wales. In 2015 the word was added to the Oxford English Dictionary. In general a fatberg is a rock-like mass of waste matter in a sewer system formed by the combination of flushed non-biodegradable solids, such as wet wipes, and congealed grease or cooking fat. Fatbergs have been around since humans invented sewer systems and date back to Roman times when slaves were used to clean out effected areas. Because most of the mass cannot be seen, the term fatberg is used.

How do they form?

Fatbergs are basically a combination of fats, oils and grease (FOG) that congeal forming solid deposits in the collection system or at a lift station. These obstructions usually form at rough surfaces of sewers where the fluid flow becomes turbulent. All that FOG, along with human waste, settles into crevices in the sewer pipes. The fat can also interact with calcium that can either come from concrete pipes or water in the system that has flowed over concrete and undergoes the process of saponification, or turning into soap.

Recently the problem has increased due to the use of so called “flushable wipes”. Kimberly Worsham, founder of FLUSH (Facilitated Learning for Universal Sanitation and Hygiene) describes wet wipes as “absorbent cotton bastards” that, unlike toilet paper, don’t dissolve in water but instead are great at grabbing grease. “Imagine a bunch of fat-soaked wet wipes in a sewer about 2 feet wide—they’re going to get together and clump up.”

How big are they?

Fatbergs can be very large and can cause sewer backups. In 2017 a fatberg of congealed fat, wet wipes, and waste was discovered under the streets of Baltimore, Maryland that caused the spillage of 1.2 million gallons of sewage into Jones Falls.[1]. The largest fatberg in the UK was discovered in a sewer at Birchall Street in Liverpool. It weighed 440 tons and was 820 ft long. After 6 months is was still being removed from the sewer as it is proving to be difficult to break-down using conventional tools and equipment.[2] A fatberg the size of a gas tanker truck, found in Melbourne in April 2020, is thought to have grown so big due to a toilet paper shortage brought on by COVID-19, which spurred people to buy more wet wipes.[3, 4]

How can you prevent fatberg formation?

Fatberg formation can be minimized by simple actions including: 

1. Installation of grease traps from commercial businesses. This is a common practice in the US and most cities have regulations relating to sizing and maintenance of the traps.
2. Do not add coffee grounds, fat, oils or other food items to your drain. Even though you may have a garbage disposal, try to minimize the amount of material placed in them as it ultimately can add to the load on a wastewater treatment facility.
3. Never flush wet wipes or anything other than toilet paper down the toilet. If you ever had a septic system, you know the problems and expense this will cause.

Fatberg in Macomb County, Michigan

References

• https://en.wikipedia.org/wiki/Fatberg
• https://www.mentalfloss.com/article/627079/fatberg-facts
• ¹Wells, Carrie. "'Fatberg' of congealed fat, wet wipes and waste discovered under Baltimore's streets, causing sewer overflows". The Baltimore Sun. Retrieved 26 September 2017
• ²"Monster found in liverpool sewer". www.unitedutilities.com. Retrieved 22 July 2019.
• ³"The flushed items that caused a 42-tonne 'fatberg' in Melbourne". 7NEWS.com.au. 14 April 2020. Retrieved 14 April 2020
• ⁴"Giant fatberg heavier than petrol tanker discovered in Melbourne sewer". www.9news.com.au. Retrieved 14 April 2020

Image Credit: Macomb County Public Works

Is Water Recycling the Future?

Water recycling could be the answer to one of the country's greatest challenges in the coming years as drought worsens because of climate change.

The Infrastructure Investment and Jobs Act, if signed into law, could provide $1 billion for water recycling and reuse projects, including funding for large-scale projects to ease dwindling supplies in Western states.

This explainer from Bloomberg Law offers a plain language overview of water recycling, including why direct potable reuse isn't as 'icky' as the public might think. As attention grows on these projects, public education will be a key factor to garner support. A United Nations report from 2017 also touts wastewater as the ultimate untapped resource.