Counting pathogens

March 10th, 2010
Written by Marcus de la fleur

I shared my sense about composting toilets, which are typically not allowed in a municipality such as Chicago. If so, it is usually on the grounds of public health safety concerns. The rationale, as I understand it, is that the risk of biological contamination with pathogens through the composted end product of composting toilets is considered too great.

Let’s indulge in a little experimental thinking – shall we?

What is the actual biological contamination risk from the composting toilet end product – or – how many pathogens would we set free? According to the EPA, a correctly operated and maintained composting toilet should produce “less than 200 MPN per gram of fecal coliforms”. (MPN = most probable number).

Is this safe? Well, I am not quite sure what to do with this number. So let’s look at this in a different way.

Chicago and many other cities have a combined sewer system. These systems can get overwhelmed in heavy storms and lead to discharge of raw sewage. In Chicago that raw sewage would end up in the Chicago River and Lake Michigan.

What would be the pathogen count for a raw sewage overflow from the combined sewer system in Chicago? What would be the MPN per gram of fecal coliform for such a discharge? Or, how many composting toilets could we run for how long to have equal counts, i.e. equal health risk?

I would love to know if anyone ever crunched these numbers – sitting on a composting toilet!

Tags: city of chicago, utilities, water
Posted in research | No Comments »

Old sewer stack

March 2nd, 2010
Written by Marcus de la fleur

We were very hopeful that we could reuse the existing cast iron sewer stack.

The more we got to work deconstructing the walls and gaining access to the stack, the more flaws and breaches we discovered.

Initially I thought we can fix those flaws. But after showing the stack to some experts and discussing the repairs, it became apparent that we would be better off in the long term if we replace it now.

Take for instance the floor joists that have been reduced to near nailers with the water closet branch cutting right through it.

A new stack will allow us to replace the joist with a structurally intact unit and route the water closet branch around the new joist.

Another unintended but welcome advantage is that we now have more flexibility with the bathroom layout. With the existing stack, the toilet was right next to the bathroom door.

Rather than falling onto the toilet seat upon entering the bathroom, Cathy and I prefer to move it to the other end of the bathroom.

All right then, the old stack has to go. It now dawned on me that we are talking about 30 vertical feet of heavy cast iron pipe that has to be removed.

I have to say, it instilled a lot of respect, if not fear. I had to promise Cathy not to remove it by myself. A very easy promise to make!

I solicited the help of Robert, who lives in the neighborhood and knows cast iron plumbing inside out. He asked for a sledge hammer and pounded away at the gaskets, starting at the top while I was holding the stack. With each broken gasket the two of us were able to carefully lift each section of pipe and remove it from the stack.

Within 20 minutes the stack was down. Really sort of anticlimactic, particularly once I saw the impressive 30 feet of stack reduced to a small pile of cast iron pipes on the floor.

Tags: deconstruction, utilities
Posted in deconstruction | 1 Comment »

Plumbing code variance

February 28th, 2010
Written by Marcus de la fleur

I have conflict to resolve. Following my basic environmental impact research on sewer pipes, I would prefer to use HDPE based materials. The Chicago plumbing code, on the other hand, calls for cast iron soil pipe (CISP).

What options do I have? Well, none – other than applying for a plumbing code variance on environmental grounds.

My chances? Probably very slim. I hear through the grape vine that some forces in the Department of Water Management would like to update the plumbing code so that it better reflects sustainable building technologies. Others apparently don’t want any of it. Well, I guess it doesn’t hurt asking for a variance.

I wrote up my rationales on material performance, longevity and environmental footprint, included the carbon footprint calculations and sent it off to the Department of Water Management.

The Result? My variance request was denied. So far I have not received any reasons as to why, and I don’t know if I ever will. At least I tried.

The replacement sewers that will be installed under the basement slab will now be CISP. I decided to stop worrying about it. It may not be the perfect material, but I have been assured from many sides that it should outlive us. This is somewhat reassuring. But what about the next generation? Don’t they deserve some consideration?

Tags: environmental impact, permit, utilities
Posted in permitting | No Comments »

What pipe material to use?

February 25th, 2010
Written by Marcus de la fleur

Let’s keep the momentum. Let’s rant some more about green stuff.

The old sewer clay tiles need replacing; that decision has been made. But what material should the new sewer be made of?

This decision is made for us, and the answer is given in the Chicago plumbing code. All concealed (i.e. buried) sanitary sewers within a building must be cast iron soil pipe (CISP).

Iron? For waste water? In soil? Wow – wait a minute. This doesn’t make sense! Isn’t iron subject to corrosion? It may rust from the inside and outside. We are using low flow and low flush systems, which reduces the dilution of any acid based liquids (such as urine) and increases the probability of corrosion within a cast iron sewer pipe.

We will use a high efficiency condensing boiler. The condensate from such a boiler is known to be corrosive and further increases the probability of corrosion within a CISP. What about the longevity of this thing? Once I am done replacing it, I never want to touch it again, even if I get to be a 100 years old!

CISP Institute information proceeds to inform me that cast iron pipe are highly durable and probably the best material to use. Well, this is sort of expected. But I still have a hard time believing that CISP is as corrosion resistant as HDPE (high density polyethylene) or PVC (polyvinyl chloride) piping. Resistance of HDPE pipes is rated from pH 1.5 to pH 14, according to a sales representative. So maybe I need to take this with a grain of salt too!

Because HDPE or PVC pipes have good corrosion resistance, they also maintain good flow and slide characteristics, which in turn reduce maintenance or blockage compared to CISP’s.

And there is the carbon footprint issue. Wouldn’t you expect cast iron to have a much larger carbon footprint compared to HDPE or PVC? Time to find out.

The International Centre for the Environment (ICE) at the University of Bath (England) has published the ‘Inventory of Carbon & Energy’ for various building materials. I found data for all three materials (cast HDPE, PVC and iron) and was able to calculate the following carbon footprint per linear foot of a 4 inch sewer:

Even though the cast iron sewer has the biggest carbon footprint, the CISP Institute points to the recycled content of the product and labels it green (see page 131 of the CISP and Fittings Handbook).

PVC is a distant second, but is no angel. The production of polyvinyl chloride has all sorts of environmental issues associated with it. PVC piping (such as Schedule 40) is very popular though because of its low cost and ease of installation.

HDPE appears to have the lowest carbon footprint out of the three materials. It seems to have a better reputation than PVC with regard to environmental issues and is recyclable. It is more difficult to install compared to PVC and requires fusion or welding equipment for moist pipe joints.

Thinking this all through, and assuming that I have my facts straight, I really would like to use HDPE piping for the sewer replacement.

Tags: carbon footprint, energy, recycling, utilities
Posted in research | 4 Comments »

What happened to ‘Green’

February 23rd, 2010
Written by Marcus de la fleur

After all the recent and intense focus on the sewers in the basement, I decided it was time to take a step back and look at the bigger picture.

The first thing I notice was that in the concoction of resolving technical DWV (Drain-Waste-Vent) questions, the green or sustainable aspect appeared to have fallen to the wayside.

Really, there is nothing sustainable to collecting your bathroom waste, transporting it through an elaborate sanitary sewer system with lift stations to a central location where it gets treated (to more or less ‘safe’ levels) and then dumped. The liquids get dumped into the nearest waterway, and the solids – well, most of them may end up in a landfill as landfill cover or just plain old waste. In short, this is mostly a one way waste stream with little or no recycling or reuse.

The alterative would be to process our sewage at the source. There are small onsite waste water treatment systems, if there is enough space on the property.

If there is not enough space, a large chunk of our bathroom waste could be diverted to a grey-water system and/or composting toilets.

Oops! Did I just trigger a couple of heart attacks in the Chicago and Illinois Department of Heath! Not to mention the Department of Building or Water Management.

Onsite waste water treatment would move us away from the energy hungry one way waste stream, towards an energy efficient, decentralized treatment that would allow for reuse of the end product (water and organic matter). Don’t get me wrong. I am not advocating abandoning our sanitary sewer structure. But we certainly could reduce what and how much we channel into it, even in an urban context.

Yes, there will be some challenges to overcome, such as watching what chemicals we use in our household and pour into our drains. Or accepting that the food we eat and digest one day could become the basis for growing the food we eat tomorrow.

But isn’t humanity so successful because we manage to adapt to new challenges?

At the risk of causing further casualties, let me share some links about composting toilets. Have fun sniffing around!

Tags: city of chicago, drainage, health, reuse, utilities, water
Posted in project rationales | 3 Comments »

The big sewer question

February 21st, 2010
Written by Marcus de la fleur

If we ever want to turn the basement into a third unit, flood protection will be rather important. We have inherited a check valve protection, but I am not too sure if this is the best option.

What else can we do?

Option #1

We could create a vertical separation between the waste water system for the basement and the rest of the building. In other words, the 1st and 2nd floor waste water system is gravity fed, while the basement system is pumped. Here is how it would work:

We eliminate the check valve with the sump and have the main sewer run directly to the vertical stack that service the first and second floor. All the basement waste water is plumbed into an ejector pit with a sump, which pumps all waste up to the first floor level and over into the vertical sewer stack.

If the city sewer system backs up into the house, all flood and waste water will be contained in the main sewer pipe. There is no plumbing connection that would allow the goodness to spill into the basement.

Option #2

We could keep and repair the check valve system. The check valve prevents the city system from backing up into the basement. It would be placed in an ejector pit with a sump and a sewer overflow. The waste water for the entire building is thus gravity fed…

… with one small exception, and that is if city system floods and the check valve closes. Once this happens, the pump engages and all waste water from the house is pumped out of the building.

Pros and Cons

Option #1 (see sketch above) would give us the flood protection we seek. The bathrooms and kitchens on the 1st and 2nd floor are gravity fed and would always remain operable. Not so for the basement plumbing, where use would be restricted during any power outage, which would disable the sump for the basement waste water system.

Option #2 (see sketch above) also gives us the necessary flood protection and is highly efficient as all waste water is gravity fed. A power outage in this case would only affect us during flooding, disabling the sump when the check valve is closed.

Should this ever happen, we still would be in good shape because we plan to use low-flow fixtures throughout the house. I calculated that we could store about 30 to 40 gallons of waste water in the 4 inch main sewer line, before it would spill out the basement floor drains. With 1.1 gallons-per-flush toilets, we could use the bathroom up to 25 times.

This logic of storing waste water in the sewer line will only work if I am disconnecting the downspouts from the sewer, which the city won’t allow. If I keep the existing roof downspout connected, the roof runoff would certainly flood the basement – if the power is out.

Option #1, on the other hand, would avoid this problem altogether, as all roof runoff and waste water is contained in the main sewer line and nothing can spill into the basement.

I also have to look at the energy side of things, if I would like to keep the ultimate goal of a zero energy building alive. The beauty of Option #2 is that a law of physics does the work for us. The system runs on gravity. The sump at the check valve may only have to kick in once it floods, say once or twice a year if that.

Not so with Option #1, where the sump in the ejector pit will kick in each time a plumbing fixture in the basement is used. This, over the course of a year, could result in major kilowatt usage and would not help with lowering our energy consumption.

This is quite a pickle, isn’t it? If you have a good idea or the solution, please let us know!

Tags: city of chicago, drainage, energy, layout, utilities, water
Posted in water management | 9 Comments »

A good day…

February 19th, 2010
Written by Marcus de la fleur

… because I got to be frugal again!

Back in December I purchased salvaged insulation for the basement floor. It was half as much as I need and I kept looking for more, without any luck. Would I run out of time? Well, that is sort of ridiculous (at least in hindsight) because I still have quite a bit of work ahead of me before I can install the insulation.

This week I ran into another source for salvaged insulation, called the Insulation Depot. I found a local reseller and finally have all the insulation I need.

This time, the sheets are not the XPS type, but the even better performing ISO type. In addition, the ISO sheets have less of an environmental impact, as Tom McGrath pointed out in a blog comment.

Whether XPS or ISO, I get the feel-good factor knowing that this salvaged material is going to good use under my basement floor, and not into the landfill! But for now, it is just sitting, waiting for me to get done with the sewers.

Tags: insulation, reuse, salvaging
Posted in general construction | No Comments »

Deciphering the existing sewer

February 18th, 2010
Written by Marcus de la fleur

After I was done exposing the sewers, I just scratched my head looking at the layout. But with time, I pieced together the intent and figured out how it worked.

At the north end of the building, where the sewer exits toward the street, I have this cast iron piece, which turns out to be a check valve. This valve prevents sewage from backing up into the basement if the city sewer system gets overwhelmed. It is probably also the reason why we found no evidence of flooding in the basement.

Having sewage backing up into the basement is a real issue in Chicago, with its combined sewer system. A combined system basically transports sewage from buildings along with stormwater runoff from building, streets and parking lots in one and the same pipe system.

If it rains really hard, that pipe system may not have enough flow capacity to handle the runoff volume, which can lead to the infamous basement flooding. A check valve can prevent this.

But, once the check valve is closed, how does any sewage leave the building? This is where this other piece of pipe comes into play – the overflow.

With the valve closed, and sewage stacking up in the pipe, it eventually will spill out through the overflow into an ejector pit. I have the ejector pit already removed, but it is basically a round catch basin, 18 inches across and 30 inches deep.

At the bottom of the pit is a sump that picks up any spill over and pumps it under pressure into the street side of the check valve.

A check valve like this needs regular maintenance, such as greasing once a year. Our check valve here hasn’t seen any maintenance in God knows how many years. I am even not sure if it still works.

The sump pump also needs regular checking to make sure that it will work when needed, i.e. during flooding. Flooding usually comes with heavy storms, which may also cause a power outage. In that case, I am still protected from sewage backing up into the building thanks to the check valve, but I can’t use the bathrooms because the pump won’t work - unless I have a battery backup.

Huh! I don’t know about this. Should I keep the system with the check valve and sump, or should I look for another solution?

Tags: utilities, water
Posted in research | 2 Comments »

Finding the existing sewer

February 16th, 2010
Written by Marcus de la fleur

The decision to start over in the basement with a new floor presents a once in a lifetime opportunity to check on the sewer lines under the building.

To find and trace the existing sewers, I started excavating at the vertical stacks and followed the piping from there.

What a discovery process! I found sewer branches I did not expect. I stumbled on old abandoned drains that were still connected to the system. And I never could be too sure which direction the pipe would snake next.

With the sewers exposed we can determine what problems need fixing. And problems there are! All the underground sewer pipes are old clay tile with mortar joints at the gaskets. That mortar has a reputation to crack and erode, and my sewers were no exception. As if that is not bad enough, a number of pipes had cracked or broken gaskets.

Some of the sewer tiles even had holes that were patched half-heartedly. There is no repairing here! We are better of replacing all the lines with new ones. This way we hopefully never have to touch the underground sewers again.

Tags: utilities, water
Posted in general construction | 2 Comments »

Do you live there?

February 11th, 2010
Written by Catherine Haibach

As you can imagine, this project is a big part of our lives. And we talk about it a lot. Not so much as to bore people, but our friends and neighbors frequently ask us for an update.

Just about every conversation includes the question, “Do you live there yet?” Of course the answer to that is no. There is no electricity, no plumbing and of course no heat. We’ll live there someday, but not anytime soon.

So where do we live?

You may recall that we had been working on a project in Elmhurst for the past few years. Last spring when we bought this building on 15th St. we clocked our travel to the city and back to Elmhurst at 45 miles, round-trip. We did that trip many times in the spring of 2009. That is certainly not sustainable, nor was it any help to our sanity.

We decided we really needed a place in the city … but how would we find a comforting home on a temporary basis? One day we were at brunch with some very cool friends at their place, the HUB Housing Cooperative. (HUB stands for “Housing for Urban Bicyclists.”) As it turns out, they had a unit for sale and our friend Ted was interested in renting it to us. So we moved in last Memorial Day weekend.

The HUB is a six-unit co-op right at 24th and Marshall Boulevards in the Little Village neighborhood. It’s an intentional community comprised of 11 people, 4 cats, 2 dogs, 3 worm bins and more than 50 bikes. The group meets once a week to talk about business and there are lots of social opportunities. I’ve known many of the people who live here for about 10 years through Critical Mass and other bicycling activities. They are truly a great bunch.

The unit we’re living in right now is for sale. It’s about 1,000 square feet with big windows and lots of light. And lots of built-in friends. The kitchen looks out onto the boulevard. If you think you might be interested in buying the share of the co-op that is this unit, please let us know and we’ll pass your info along.

Tags: community, neighborhood
Posted in starting up | 1 Comment »

Counting pathogens

Old sewer stack

Plumbing code variance

What pipe material to use?

What happened to ‘Green’