Friday, November 5th, 2010

Replay: A Better Road to Clean Water Act Compliance

I’ve noted before that the astronomical cost of Clean Water Act compliance for our cities was a killer. Most older cities are also struggling with deteriorated street infrastructure that would require another massive dose of spending to correct. Also, in the Midwest, most cities have street networks that are not even right in their very conception for the modern day anyway. And, they need to make major investments to create a more green city as well. A plan out of Philadelphia shows the way to kill three birds with one stone.

With the most ambitious program of its kind in America, Philly is looking to remediate its combined sewer overflow problem with a massive program of green building designed to prevent the problem in the first place.

Philadelphia has announced a $1.6 billion plan to transform the city over the next 20 years by embracing its storm water – instead of hustling it down sewers and into rivers as fast as possible.

The proposal, which several experts called the nation’s most ambitious, reimagines the city as an oasis of rain gardens, green roofs, thousands of additional trees, porous pavement, and more.

All would act as sponges to absorb – or at least stall – the billions of gallons of rainwater that overwhelm the city sewer system every year.

The plan’s complex funding formula would raise rates somewhat but also attract grants and encourage private investment.

Further, the Water Department says the city’s greening would result in more jobs, higher property values, better air quality, less energy use, and even fewer deaths – from excess heat.
[ link to online article expired ]

For those who aren’t familiar with the term, a combined sewer is where storm water runoff and sewage from buildings is carried in the same pipes. This was how sewers were built back in the day and were a huge improvement in public sanitation at the time. However, in heavy rains, the storm water runoff overwhelms the capacity of the treatment system, and the rest backs up in basements, pools on the streets, or is simply dumped into a nearby river, contaminating the environment with untreated sewage. Cities are being forced to largely eliminate these combined sewer overflows as part of the Clean Water Act.

The typical solution to this is to spend a few billion dollars building a “deep tunnel”. This is a huge storage pipe bored into bedrock deep underground, which holds excess sewage until after the storm when the treatment plant can process it.

There are a few problems with deep tunnels:

  • They are ridiculously expensive. Washington, DC is spending $2.2 billion on one, Indianapolis $1.6 billion, Cincinnati $3.5 billion, and Cleveland $5 billion – or thereabouts. The prices seem to vary depending on the source you read, but the operative term is always “billion”.
  • Like all projects designed to deal with peak of the peak capacity, it will be un-utilized or under-utilized 90% of the time. It’s mostly wasted capacity. If you can, it is generally better to use demand management techniques to smooth out demand spikes, such as congestion pricing for roads.
  • It’s a hack. We’re still basically taking clean water (well, not entirely clean, but that’s another post), combining it with raw sewage, and creating even bigger amount of, well, sewage. That doesn’t sound too smart.
  • It adds zero to the city. What does your city get for a deep tunnel no one can see? Not much. The environmental benefits will never generate a rational economic or recreational ROI and no one even attempts to justify it on that basis. We are simply doing this because we’ve decided it is the right thing to do.

The cost of this will add yet another incentive for people to move to suburban or exurban districts that are not part of the combined sewer zone to escape paying the sky high bills that will result. Those newer areas were built from the ground up with separate storm water and sanitary sewer systems. Sewer bills in Indianapolis are on their way to over $100 per month – triple suburban rates. This will certainly hurt low income people and make them look even more strongly at the collar counties.

Philadelphia is showing a better way to tackle this problem. Instead of building a deep tunnel for billions and getting more or less no return, it is looking to spend money at get something for it in terms of improved street and green infrastructure and more trees and greenery – while preventing the creation of billions of gallons of contaminated water in the first place. In short, exactly the type of demand management solution we should be looking at. There’s no guarantee the EPA will go along with them. Cincinnati floated this idea and it got shot down. But given the potentially huge benefits, it ought to be pushed with full vigor.

Consider the possibilities. Instead of a place like Indianapolis tripling sewer rates to dig a deep tunnel, then having to turn around and sell its water utility (a moving Cincinnati is also looking at) to raise funds to repave streets that, even if fixed up, still are not relevant to reinvigorating the urban core for the 21st century, why not instead do something like this? I was thinking about it just the other day walking past a construction zone on the Cultural Trail and seeing the rain gardens being built there. Why not use the billions for sewers to rebuild the streets with rain gardens, new curbs and sidewalks, bike lanes, new permeable pavements, trees and native grasses, etc? This would not be gold plated a la the Cultural Trail, but just what the new basics of a thriving urban environment today ought to look like. Think of the possibilities:

  • CSO overflows fixed
  • Streets re-imagined and upgraded
  • New state of the art green infrastructure built

That’s called a trifecta. Any city that hasn’t already built a deep tunnel should launch a full court press on this – even it has already reached a settlement with the EPA. There are certainly challenges to overcome – I hear permeable asphalt can’t be salted, for example, a problem in a region with lots of snow – but technology is getting better every day and where there’s a will, we can find the way.

Cities that don’t do this, and go with the old school approach, face the serious of risk of building the civic equivalent of the new Comiskey Park. That is, the last of the 70’s style stadiums that were obsolete as soon as they opened as a new era of fan friendly ballparks debuted. Don’t be that city. Kudos to Philadelphia for really leading the charge.

President Obama is bringing a new focus on cities to the White House. If I could pick only one area he could make a huge difference in for our cities, it is in changing the game on Clean Water Act compliance. If he pressed the EPA to embrace a forward looking vision of using this type of green infrastructure program, it could be a huge force in increasing the attractiveness of our urban cores in an era when that is more critical than ever. And if the feds picked up the cost of this – and nothing would help cities more since it would remove a huge financial disincentive to live in the city – it would be the ultimate urban game changer. I’d urge the President to make this happen and our city leaders to go all out for it on their end.

This post originally ran on October 13, 2009.

Topics: Public Policy, Strategic Planning, Sustainability, Technology
Cities: Philadelphia

3 Responses to “Replay: A Better Road to Clean Water Act Compliance”

  1. Franny says:

    In addition to a really impressive array of materials from the Philadelphia Water Dept., a number of schools have taken up the challenge of stormwater management in Philadelphia and are offering classes based on achieving Philly’s stated goal of 50% retention of the first inch of rainwater. Urban planning students at MIT are currently working on design projects in the Mill Creek watershed, in West Philly. Information about our work is available at the website of the West Philadelphia Landscape Project (


  2. Brian W says:

    Does the President have enough political capital left to recapture the push for better infrastructure? I don’t know. I applaud the Livable Communities partnership between HUD, EPA, and DOT and that partnership seems to echo your recommendations to do combined projects at the local level. Very recently I have noticed that urban stream restorations are becoming quite popular and effective tools for stormwater management and catalyzing community redevelopment.

  3. Great to see Philly coming together on this issue. Talk about the city of Brotherly Love!

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