The obstacles to building affordable housing can be daunting. Though it’s often towns themselves that present the biggest challenge through exclusionary zoning, sometimes the infrastructure simply isn’t in place to allow for the kind of density that most often leads to affordability.

That frequently means sewers. Whether we like to talk about it or not, waste disposal is a key factor in development. And none of it is cheap.

A recent opinion piece at LymeLine.com gets to this problem. As written by Eric Knapp, who is the Town of Old Lyme’s land use coordinator: “If the State of Connecticut is serious about rebalancing the housing market, here is what works: infrastructure and public services. If there was both public water and municipal septic disposal, there could be additional density.”

Wastewater disposal falls under two broad categories – sewer and septic. Sewer systems are typically large and serve many thousands of people, often across municipalities; septic systems are usually localized for one residence. “Community septic” systems, functionally self-contained small sewer systems, can safely serve dozens or even hundreds of units. While expensive, they are an important option to consider in some parts of Connecticut. 

Regardless of the type of disposal, the technology is roughly the same. Wastewater is treated and rereleased into the ecosystem in a manner that protects everyone’s environmental health.

Among the biggest differences between these approaches is space. Septic systems require a lot of acreage, including a leaching field, which is a system of trenches or beds in the ground that allow water from a septic tank to seep back into the soil. Use of septic mostly precludes density, which is why some towns like it so much.

Sewers, by contrast, require only a hookup to a wider system, where treatment might be miles away by pipe. Sewers are what make dense development possible, which leads to a situation where, as Knapp says, “the official policy of most towns is still ‘sewer avoidance,’ which is an effective way to discourage further density.”

In other words, towns know that density requires sewers. Towns that don’t want any additional density have been known to limit the use of sewers, which makes achieving affordability that much harder. It’s a particular problem in the southeast corner of the state on Long Island Sound.

None of this means sewers are the right answer everywhere. The price of extensions and hookups can run into the millions of dollars, though state and federal aid is often available. In addition, much more can be done to safely increase density by allowing “missing middle” or lower density on single-family lots served by septic. A McMansion may have the same septic impact as a four-unit apartment building.

Either way, we need to take infrastructure seriously. “Sewer avoidance” policies are keeping our state sprawled, and contributing to our affordability crisis.