I see a parallel between Omaha’s $1.66 billion combined sewer overhaul project, the decisions and behaviors that led to the sewer system problem, and climate change. Anyone else?
First, what the heck is Omaha’s sewer project for? A combined sewer provides a route for both stormwater and “sanitary” sewage (basically, anything that goes down a drain in your home, including the toilet). About 43 square miles of eastern Omaha—primarily built before 1960—is serviced by 510 miles of combined sewers.
Map showing the portion of Omaha with a combined sewer system.
With as little as 0.1″ of rainfall, the stormwater combines with the sewage and causes the untreated, raw sewage to discharge directly into both the Missouri River and Papillion Creek (which feeds into the Missouri River)—known as a Combined Sewer Overflow, or “CSO.” If you don’t want to have crap, urine, and other chemicals from homes in your waterways, then you should like the idea of fixing the combined sewers to reduce the number of annual CSO events in Omaha from 52 per year to four or less per year.
Graphic schematic of a combined sewer.
If you aren’t sure if having crap, urine, and household chemicals in your waterways is a bad thing, consider that raw sewage can be a source for disease-causing organisms (in addition to being smelly and unsightly) and chemical pollutants that cause problems for fish and other aquatic wildlife (i.e., birds, amphibians, reptiles). By the way, much of Omaha’s drinking water comes from the Missouri River, and even though it is treated first, wouldn’t you rather know it started off a little bit cleaner?)
Second, how did we get to the point where this sewer project needs to happen? Well, it is a combination of two things. One thing is real and the other is artificial. The artificial thing is regulation from the U.S. Environmental Protection Agency. Basically, the EPA has effectively set a limit on the number of CSO events a community’s combined sewer can cause per year. The Federal Government has found that more than 770 communities across the country have a CSO problem, so Omaha is not alone here.
Map showing locations of other communities subject to EPA's CSO regulations.
The real thing that has created the need for this work is the storm water management paradigm in Omaha. A 0.1″ rainfall event may not seem like much, but consider what happens to that water. All the water from a rooftop is concentrated into a gutter, which then combines the flow with other gutters and the flow from impervious surfaces like asphalt, concrete, and packed dirt and takes that to the storm drain, which in a combined sewer system overloads the “sanitary” sewer leading to CSO events where all that waste and chemicals goes directly into our waterways. Over watering and over-fertilizing your lawn can contribute to harmful runoff as well. If, over time, Omaha and its residents had been investing in more diverse and dynamic storm water management in the form of storm water retention ponds, rain gardens, bioswales, porous pavements, green roofs, and rainwater capture systems like rain barrels, it is possible the combined system would have created fewer CSO events, maybe even few enough to avoid EPA’s regulations.
Now, in order to fix the problem of CSO events in Omaha, we need to collectively spend $1.66 billion dollars within 15 years rather than investing a little bit over the past 150 years to prevent overburdening our combined system today. And finally, ladies and gentlemen, is the three-step analogy to climate change!
- In the combined sewer system, the problem input is too much combined storm water and sewage. In climate change, the problem input is greenhouse gases.
- In the combined sewer system, the sewer has only so much capacity for sewage and rainwater before it overflows and causes a CSO event. In climate change, our atmosphere and planet has only so much capacity to deal with greenhouse gases while maintaining the equilibrium with which every living human and current ecosystem on earth is familiar.
- In the combined sewer system, the undesirable outcome is a CSO event, directly caused by the system inputs overwhelming the system’s capacity. In climate change, the undesirable events are many: rising sea levels, rising temperatures, and stronger weather events, all of which are the result of the system input overwhelming the system’s safe capacity.
Why is this analogy even worth writing about other than connecting seemingly unconnected ideas? I see a clear lesson here. In the case of the sewer system, the cost to fix the problem (mitigation) rises over time until—when there is no choice but to adapt—it is extremely, painfully costly and no one wants to pay for it all at once. Climate change is the same way. Experts estimate that every year that passes in which we do not apply serious climate change mitigation measures, the cost of adapting to it later increases by $500 billion. Yes. $500 billion every year we delay.
We missed the chance to use smart, diverse, storm water management solutions in eastern Omaha so as to avoid the lump-sum cost of fixing the combined sewer all at once now. But the good news is that we can still avoid the huge price tag of adapting to climate change in the future by investing our financial, social, and political resources in serious mitigation today.
Whether you understand that climate change is caused by human activity or you choose to believe something else, you can’t refute the evidence that our planet is getting warmer. And if you agree that our planet is getting warmer (regardless of the reason), you should agree that the smartest financial move, the fiscally responsible and conservative move, is to spend our resources now to avoid having to lay out unforeseen amounts of money at some critical point in the future.
The math of climate change is very simple. The consequences of climate change are very serious. Now that we have the cost and headache examples of what happens when a combined sewer runs amok, and can see how climate change is like sewer crap, it should be clear to see how bold action today to reduce greenhouse gas emissions can save even more money and bigger headaches down the road.