What's That Smell? Eliminating Wastewater Treatment Odors

With all this talk about public awareness of hidden water system infrastructure, it is important to point out that there are times when public awareness is definitely NOT on your side. And one of those times is when there is a stink that just doesn't go away.

Odors are generated from every phase of wastewater management including collection, treatment, and disposal, and they can cause all sorts of public relations issues, putting pressure on an utility to resolve the problem in a timely way. Certainly, managing odors is one of the most important - and yet most challenging - aspects of wastewater treatment. 

Why so challenging? Because in part there are many odor control technologies available but no single ideal solution. Some systems, like this Brownsville Public Utilities Board plant in Texas, solve odor problems by placing covers over wastewater tanks and channels and then blowing the smelly hydrogen sulfide gas through a biological tower. Others such as this Bridgeport, CN Water Pollution Control Authority plant, capture odorous offgas with coated fabric covers and treat it with a carbon system. Still others use a combination of  different measures, such as activated sludge diffusion, carbon adsorber sytems, pump station chemical feed systems, coverings and plant operation modifications. 

But fixes like these don't come easily, or cheaply. And sometimes, the problem is even more complex. Consider this story of a system in Saline, MI that has been the subject of neighbor complaints for years. Even after odor studies and abatement work, the smell just keeps getting worse. 

How can a smaller system then, with its limited funding and manpower, address odor problems effectively? The cheapest way to control odors is at their source, according to this Science Daily article, but sometimes that is simply not possible. Fortunately, researchers from the University of British Columbia may have recently developed a solution. 

Many wastewater facilities use anaerobic digestion, but is is expensive to acquire and maintain the associated odor control and biogas safety equipment needed. A much more cost-effective way to mitigate odors, these UBC researchers have discovered, is to revisit metal salts treatment. Simply adding new combinations of these common commercial metal salts during the fermentation process dramatically improves offensive odors, and also improves their ability for remove water from digested sludge. It is these unique doses/formulas and point of addition during the fermentation process that really amplifies the effectiveness of this new approach. Moreover, the cost of adopting their technique is minimal, so smaller systems can afford to test it out. 

In the meantime, if you need a quick primer on odor generation and management, the Water Environment Federation (WEF) has a 7-page factsheet explaining the problem and outlining advantages and disadvantages of various mitigation strategies. 

You can also keep an eye out for odor events right here on WaterOperator.org. For example, this Iowa training later in the month troubleshoots lagoon odor issues. Just type "odor" in the keyword search box on the event calendar page. 

Want to brainstorm with other wastewater professionals? Attend WEF's Odors and Air Pollutants Conference 2018 in Portland, Oregon in March, 2018. With sessions ranging from "Optimizing Hydrogen Peroxide Dosing" to "Odor Control Scrubber System Planning and Design," there will be many opportunities to learn in-depth solutions to any smelly situation. 

Featured Video: Nitrogen Removal in Wastewater Treatment

Nitrogen Removal in Wastewater Treatment from Steven Myers on Vimeo.

Featured Videos: Clarifier Basics & State Point Analysis

Hurricanes, Flooding and Wastewater Plants: What Have We Learned?

In recent months, there have been dozens of reports of wastewater treatment plants that have flooded due to heavy hurricane rains and storm surges in Florida, Texas, Puerto Rico and beyond. Both the sheer number of plants affected, and the extent and duration of the flooding have posed significant public health and technical challenges, often stretching communities to their limits. 

To add to these problems, many rural utilities were already struggling to keep their systems operating before the storms struck, so costly, complicated repairs or replacements of damaged infrastructure is simply not an option. For example, Patton Village, Texas had just completed a new wastewater plant — the first of its kind in their community — before Hurricane Harvey struck. Now they can only hope that USDA/FEMA emergency funding will be available to help repair the damage. And even once the systems are up and running again, it is not a given that water systems can count on water rate income to help with their O&M bills - many residents have fled their flood-damaged homes for good.  

The sad truth is that lately, floods have been affecting wastewater plants with unfortunate regularity, and not just in hurricane-prone areas. For example, in Central Illinois, the small town of Hutsonville's wastewater treatment plant has flooded 3 times in the last 2 years, up from once every 5 years, according to its contract operator Shannon Woodward of Connor & Connor, Inc.

Woodward's first piece of advice is not to build on a floodplain, but he also acknowledges that many communities do not have the capital funds for effective protective measures or relocation, and so operators must deal with the hand they are given. His second piece of advice: "Make sure all electrical controls, switch gears and transformers are above the flood stage. That way, when the flood waters subside, you don't have equipment loss and can get back into operation — even if it takes 3 to 6 weeks for the waters to recede." 

Mason City, another small town in Illinois, was able to fund improvements after a flood in 2008 cut off the town’s water supply and nearly overflowed the capacity of its wastewater system. The following year, the city built a stone wall around the water plant, installed flood sensors on the local river, and built effluent pumping stations for the wastewater plant. 

And this article tells the damage and recovery stories of two flooded wastewater plants in Rhode Island. According to the operators of these plants, it is essential to have a flood plan, even if you think your facility is protected. In addition, they maintain it is important to involve wastewater treatment personnel in emergency response exercises or in the incident command structure. On a practical level, the operators encourage SCADA systems to be elevated on the second floor in the operations building if possible. And lastly, they recommend you back up your files and documents electronically. Papers get wet, they say: move them to a dry storage facility. 

Finally, while every community has different characteristics and needs, there are some universal preparedness strategies for wastewater plants. The US EPA recommends practicing mitigation options as the best way to prevent floodwater from invasively appearing. Some of these options include crafting barriers around key assets, having an emergency back-up generator, and keeping key electrical equipment elevated. You can learn more about these options here, or you can watch this helpful video. In addition, many states have their own guidances, such as this one from Minnesota’s Pollution Control Agency.

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The Roundup: Online Wastewater Training Courses

Photo Credit: Zenia Nunez

Managing wastewater is a big task. Whether you need to train new personnel or simply brush up on professional development, we’ve rounded up accessible wastewater training opportunities on the web, listed in alphabetical order. These courses require a fee in exchange for Continuing Education Credit (CEUs). To find free webinars on wastewater, without CEUs, check the WaterOperator.org events calendar.

On-demand courses

360water

The one hour courses include some wastewater treatment, analysis, and safety for $30 each. 360water courses are good for CEUs in most states.

Cost: $30

Approved Environment, Inc.

These online courses are good for CEUs in 18 states. Courses range from 1 hour topic courses (e.g. odor control or ozone disinfection) for $20.25 each, to a 16-hour Wastewater Certification Review for $275.

Cost: $20.25 - $275

CEU Plan

CEU Plan will filter thee course topics available to you depending on which are accepted for credit in your state. (There are no options for the U.S. Virgin Islands, Unincorporated Territories or the Caribbean.)  Prices vary by state, but the widely offered 1 hour activated sludge courses, ranges in price from $12 to $15, and some states offer course packages that bundle together 6 hours of wastewater or collections topics for an $80-$86 enrollment fee.

Cost: $12 - $86

Office of Water Programs, California State University Sacramento

A five-part course designed to train operators to safely and effectively operate and maintain wastewater treatment plants. All courses are online and include lessons, readings, student exercises, and online exams. Supplementary materials for purchase include companion CDs with readings and student and a manual Operation of Wastewater Treatment Plants, Volume I.

Cost: Enrollment $50 - $148

Technical Learning College

Accepted in many states, TLC’s courses are written manuals and assignments available for download, with fees from $50 to $300 for a wide variety of topics, from pretreatment to pumps.

Cost: $50-300

TREEO Center

TREEO offers online courses in wastewater collection and treatment (listed at the bottom of the linked page). These self-paced courses look more like traditional classes than most other options. However, they are pricey at $325 per course, which includes a textbook shipped to you.

Cost: $325

Scheduled Courses

Arkansas Environmental Training Academy
AETA offers wastewater courses scheduled online throughout the year for a relatively low price. Descriptions are available here.
Cost: $75 to $180

Washington Environmental Training Center
A course on wastewater laboratory procedures begins June 26 (today) and costs $343 for 2 credits. A wastewater collection course begins September 25 at $479 for 3 credits. has a few online options, mostly for water operators, but they do have a $479 for 3 credits.
Cost: $343 - $479

Did we miss any online wastewater courses you’d recommend? Please share a link in the comments section below.

Featured Video: Community Onsite Options

If you live in a community with a large number of failing septic tanks, you're probably already familiar with the downsides of these systems: the damage to local water quality, the threats to public health. The smell. What you may not know is what you can do about it. Of course, one option is to convert the entire community to a conventional wastewater collection and treatment system. This prevents putting the entire community at the mercy of that one guy who just won't pump or repair his tank, and it ensures that a professional is involved in the wastewater treatment process.

But what if a conventional sewer system is logistically or financially impractical for your community? Are you stuck dealing with smelly, dirty water leaks forever? Thankfully, the answer is no. This 17-minute video discusses the opportunities offered by community onsite management systems. These systems combine the effluent from individual septic tanks into a community-wide leachfield, and often involve mandating activities such as basic maintenance and monitoring. The video includes profiles of five communities (most of them rural) that successfully rehabilitated failing septic systems and combined them into a community onsite management system.

If you're interested in learning more about septic systems and decentralized wastewater systems (which involve community-level septic options), browse our document database using the category Decentralized WW Systems. You can also visit NESC's wastewater page for more on the septic resources they collect and offer.

Featured Video: Use of Davidson Pie

What's a holiday season without a little pie? The Davidson Pie might not be very tasty, but it can help you work math problems assisting with chemical addition and process control at both water and wastewater utilities. This 3-minute video explains the construction of the pie and works an example problem using it.

For more water and wastewater math help, search our document database using the "Certification/Exam Prep" category filter and the word "math" (without the quote marks) in the keyword filter.

Featured Video: Will It Flush?

With the holidays coming up, a lot of your customers may be getting particularly creative with their flushing activities. After all, for a lot of us the holidays mean a lot of hectic activity and a house full of guests. When the house is full, the trash is full, and the bathroom's getting worked overtime, sometimes standards can relax a bit. And who can blame them? A lot of products do say "flushable," right there on the label.

If you think your customers could use some extra information on how several commonly-flushed products actually behave once they're out of sight, this video might help. In it, Pre-Treatment Technician Tracy Stevens from the City of Spokane Department of Wastewater Management uses a jar test setup to demonstrate the dangers to sewers and wastewater pumps posed by facial tissues, flushable wipes, dental floss, Q-Tips, feminine hygiene products, and flushable kitty litter. If you need to give someone a refresher on the flushable, this video could be a great place to start.

For more on utilities' efforts to fight flushables and fatbergs, search "flushable" (without the quote marks) in the keyword filter box of our document database. The City of Portland also has a list of items not to flush or put down your sink:

• disposable diapers
• tampons and tampon applicators
• sanitary napkins
• cotton balls and swabs
• mini or maxi pads
• condoms
• cleaning wipes of any kind
• facial tissue
• bandages and bandage wrappings
• automotive fluids
• paint, solvents, sealants and thinners
• poisons and hazardous waste
• cooking grease