Municipalities across the U.S. have one of two types of sewer systems. A separate sanitary sewer may be what most people assume is in their city. It’s a sewer where water from showers, sinks, and toilets goes into the sewers and travels to wastewater treatment plants. In the first half of the 1900s, combined sewers were also allowed. With these systems, wastewater from homes and businesses goes into sewers, but so does storm runoff from rains and melting snow.
When was the last time your facility was upgraded? Planning needs to be a key consideration to ensure your wastewater treatment plant is managing flow rates of wastewater and, possibly, stormwater runoff. If it’s been a while since your district has discussed facility upgrades, you’re long overdue. It’s time to ask these questions.
What Type of Sewer System Do We Have?
What type of sewer system does your municipality have? Are you a separate sanitary sewer system? Generally, you won’t face too much strain with higher flow rates, but water can enter the system unexpectedly during heavy rains. If there are any leaking seals, cracks in the sewer system, or failing connections, stormwater runoff may leak into your system unexpectedly.
If there is a blockage, it can cause wastewater to back up and overflow in areas of your plant. Failing equipment and vandalism are other risks separate sanitary sewer wastewater treatment plants face. This can cause sewer overflows or create issues in your wastewater treatment plant’s collection system.
You may have an older wastewater treatment plant that is a combined sewer. Extremely heavy rainfall can wreak havoc on your system. If there are flooding rains, your plant could end up with overflow that has to be released as untreated sewage into a nearby lake or river. This can be disastrous.
In 1994, the EPA took steps to reduce the number of combined sewer systems in the U.S. Ideally, the hopes were that municipalities would separate their sewer systems and storm runoff drains. By 2000, the U.S. Congress required remaining cities and towns with combined sewer systems to meet the EPA’s guidelines requiring at least nine controls in place to reduce the impact of sewage overflows, such as retention basins or expanding the wastewater treatment facility’s capacity.
You might think that in 20+ years since the EPA’s guidelines changed that all remaining combined sewer systems had been corrected. It’s not the case. One Vermont city facing such changes drafted its proposal in 2019. It involves new valve vaults, new flow controls, a larger storage tank, a new screening structure, and a new grinder pumping station. Plus, miles of sewer lines need to be added or improved. The upgrades are targeted to be completed by 2032.
Have We Been Fined or Warned Recently? If So, Why?
Has your wastewater treatment plant received fines or warnings lately? When a wastewater treatment plant receives its permits, it’s given limits to meet before the wastewater is released. A plant has to properly treat wastewater to achieve the goals set forth in permits.
The city of Wapato, Washington, was warned and agreed to pay the EPA $25,750 in penalties for discharging treated wastewater that exceeded the limits listed in the facility’s permits. Zinc was one of the pollutants triggering the warning and fine.
If your equipment isn’t doing all it should, it’s time to evaluate the equipment and processes you have in place. Make upgrades as needed to ensure you’re able to treat wastewater correctly before it’s discharged. Adding new pumps, larger storage tanks, and better aeration systems all help improve efficiency. Computerized equipment that measures increasing and decreasing flows is another cost-effective change to consider.
What Are Our Peak Flow Rates and What’s Our Capacity?
You have a permit from the government that states the measures you must meet. It includes things like how much chlorine can remain in treated wastewater that you send back to the public water system or a local river or lake.
Another consideration is how much wastewater comes into your treatment plant each day and how much your equipment is capable of handling. Your equipment needs to be able to handle peak flows. Leaving a little extra room for the unexpected is helpful.
If you’re finding your plant is often at capacity, it’s time to consider making upgrades. As more people or businesses come to town, water usage increases. That means more wastewater entering the sewers. Your plant needs to be able to handle the growth.
What happens if new developments are leading to more wastewater than expected. Say a new condo complex comes in and planners estimate an average of 70 gallons per day from each resident. But, some people in those condos are using far more. An expert will need to rule out leaking toilet seals or similar issues. If it’s simply that people are using more water than estimated, it can become a headache. You can’t kick people out of their homes, so you have to look at growing the capacity of your plant.
Have Weather Patterns Shifted Unexpectedly?
What about the weather in your area? Global warming is causing some unexpected shifts in weather patterns that are impacting cities’ wastewater treatment systems. Detroit saw flooding after heavy rainfall hit in mid-March. The excessive rainfall caused a river to flood and back up the sewer system. Pumping systems became overwhelmed, so untreated sewage had to be released elsewhere.
Back in 2020, Concord, California’s wastewater treatment plant was used to flow rates of around 50 million gallons a day. Flooding rains led to an increase to 200 million gallons. The facility couldn’t keep up with it. While the plant is a separate sanitary wastewater system, stormwater entered through leaking mains and pipes. The city had to divert incoming wastewater and move some into storage tanks to be treated at a later date.
Have We Addressed Ways to Boost Efficiency?
Finally, look at your plant’s efficiency. If there are cost-effective ways to boost efficiency, make the improvements. You might consider using available grants or government loans to add solar panels to reduce your facility’s electricity rates. Wind power is another option.
You might want to upgrade old equipment for newer pumps and motors that don’t use as much power. For example, a Magna Rotor Aerator offers high efficiency for a lower operating cost. Even maintenance costs are reduced thanks to a hinged access panel. Aeration will cost less, saving money on electricity consumption, so the money you spend pays for itself through the savings you gain.
Alternative fuel is another idea to embrace. Instead of using oil, propane, or electric heaters to keep your workers warm enough in colder months, upgrade to a heating system that captures something you have plenty of within your plant. Add systems that capture methane and convert it into gas that can heat your facility.
Are you interested in learning more about upgrades that improve efficiency, lower your overall costs, and ensure you can meet your plant’s increased flow rates? Talk to the experts at Lakeside Equipment. Our engineers have decades of experience and help ensure you have a quality solution to ensure you have a wastewater treatment plant that meets, if not exceeds, your municipality’s needs.