Posts Tagged ‘water’

Nail biter

Sunday, June 27th, 2010
Written by Marcus de la fleur

We had an interesting day on Wednesday June 23rd. It started with a small earthquake shortly after lunch, followed by severe storms that quickly moved into the area. This was the first time that I heard the tornado sirens come on in Chicago.

I was working on masonry repairs in the basement when this all happened, the right place to be when the sirens go off! And the rain – it is not often that you get to see that kind of persistent downpour.

So much rain fell in fact, that I suddenly noticed a small trickle coming out of the storm sewer pipe that currently dead ends in the old grease trap.

sewer-layout-008

Eventually, that storm sewer stub will be connected to the downspout overflow, but we are not there yet, nor do we have an end cap on it. So – water starts to trickle from the city system out of the storm sewer into the grease trap.

Other than this one line, everything else is flood proof due to the sewer layout and check valve.

I was doing something else for a few seconds, and the next time I turned around the grease trap was almost full and the new storm line was submerged in water.

flooding-001

Just by the movement of the water, I could tell that the water was now gushing from the city system into the grease trap, and the water level kept rising.

I went into emergency mode, gathered all the tools from the basement and relocated them to the 1st floor, disconnected anything electrical that was close to the basement floor, and told the dog to get ready for a swim.

flooding-002

All things considered, I was sort of lucky. The downpour has been going on for a while and must have washed any raw sewage out of the combined city system. The water that was gushing into the grease trap appeared to be street runoff and did not smell of sewage, nor did I have any turds floating around (thankfully).

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Well, as you see I had a few seconds to take pictures of the rising water. At this point it was slowly filling up the perimeter drain and gravel base under the basement floor. That hidden storage volume assured that the water rose slowly.

flooding-004

It kept rising to about one and a half inches below the top of the new concrete floor. The rain started to ease, the water stopped rising, and finally the flow reversed back into the city system. Whew, what a close call!

This was quite an experience, and I have wasted no time getting the storm sewer stub temporarily connected to the downspout.

flooding-005

This will stop access of water from the combined city sewer into our basement and prevent this kind of nail biter for the foreseeable future.

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Water service extension

Wednesday, May 5th, 2010
Written by Marcus de la fleur

We were lucky in that we can keep the existing one inch water service coming into the building. Earlier last year, we had difficulties finding it because it had been removed by scavengers. We finally located the snapped off end at the northeast corner of the basement – at the street side.

What do we do with the snapped off end? Well, we need to connect to it to run the line back into the building, into the utility room. The question is if we should run the line in the ceiling or under the basement floor.

The basement has a ceiling height of 7 feet and 6 inches, just about meeting building code. If I want to hide the line in the ceiling, I would have to drill through a whole bunch of floor joists – not something I want to do. Floor joists are best left untouched.

I could leave it exposed under the ceiling, although I would need to insulate the copper tubing to prevent condensation. This option doesn’t tickle my fancy either.

That pretty much leaves me with the option of running the line under the basement floor. Good idea, but I got conflicting messages. Some sources said that building code would not allow it.

I actually can run the line under the basement floor, because I have the shut-off valve and water meter in the parkway in front of the house. Only if the shut-off valve and meter are in the basement, the water service must be routed above the floor as soon as it enters the building.

We got ourselves enough one inch copper tubing and a flare connection to connect to the existing service.

water-service-line-01

Because we connect underground, the plumbing code requires that flare connection. We run the line toward the back of the basement…

water-service-line-02

… where we have it turn up in one of the future walls. Here we have another shut-off valve, a ball valve. Because we are now above the floor, the connection of the valve to the tubing is soldered.

water-service-line-03

We got just so far, although we have a whole lot farther to go. But that should happen in due course as soon as we have our new basement floor.

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Why that storm sewer?

Sunday, April 18th, 2010
Written by Marcus de la fleur

Some of you who have read the ‘Permit – open plan review’ post, or who have noted the storm sewer in the ‘New sewer layout’ post, who know the 168 Elm pilot project and our attitude towards stormwater management may wonder why we spend money on a new storm sewer connection.

Disconnecting roof downspouts in Chicago is a tricky subject. The Chicago Green Homes Program encourages disconnecting downspouts from the sewer system. The Department of Water Management and Department of Environment are working hard on incentivizing disconnections. There is even a building code section that addresses this issue (Chapter 18-29-1101.2):

“1. Nothing in this provision shall prohibit the temporary or permanent disconnection of the roof downspout of a building from the sewer or combined sewer so long as the disconnection does not result in the drainage of water beyond the property lines of the lot on which the building is located.

2. Roofs of single-family (Class A-1) and multiple-family (Class A-2) buildings may be provided with external downspouts discharging onto a paved or landscaped area, provided the water thus discharged can be drained directly to an area drain, catch basin or street gutter connected to a public sewer, without spilling over onto adjacent property creating a public hazard or nuisance.”

That said, the plumbing inspector in the Department of Building won’t have any of it. When I raised the issue during the open plan review, I was told in no uncertain terms that disconnecting the downspouts is not an option. I would not receive project approval unless I showed a downspout to sewer connection on the plans.

I have to admit that I did not show up with engineering drawings and calculations that would have shown how I will manage the roof runoff on the property without flooding my neighbors. I think I would not have signed off either without a complete and sound design.

But when I asked for my options, like I did with the 1 inch water service, I was given none, despite the above stated code section, and despite existing precedence in Chicago.

So – do I want to fight over the disconnection, or would I rather keep a storm sewer connection?

I’d rather keep the connection to get the city’s approval and to keep going with the project. Once we are done, we may disconnect after all, if the sustainable stormwater treatment methods in the yard can handle all the runoff.

The primary rationale to deny downspout disconnections is to assure the public’s health, safety and welfare. How would a connection to the storm sewer help with that public health, safety and welfare, considering that the combined sewer system in Chicago is readily overwhelmed? Wouldn’t it just add to the flooding? Wouldn’t it be safer to siphon some of that water off and manage it outside the sewer system?

I have difficulties following the rationales and reasoning of the inspector.

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New sewer layout

Thursday, April 15th, 2010
Written by Marcus de la fleur

The big sewer question is resolved, thanks to our friend Jonathan. He commented on the post and sparked the ideas leading to the solution.

Rather than having all the basement fixtures draining through an ejector pit (Option 1) or installing a check valve (also called backwater valve) where the sewer exits the building (Option 2), we now have an Option 3:

All the basement fixtures will drain through a check valve before connecting to the main sewer line. This way all the basement plumbing is protected from flooding. Not only that, but it eliminates the need for pumping, because everything is now gravity fed.

sewer-option-03

We still could install an ejector pit with a pump upstream of the check valve. The assembly would only kick in during flooding, i.e. when the check valve for the basement plumbing is closed. Because there is no history of basement flooding in our house or on our block, in addition to the fact that I would like to get away from any pumping, we decided against it.

Furthermore, if there is flooding, the check valve would typically close only for a matter of hours, thus limiting the time of disruption for all basement fixtures.

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The water service problem

Sunday, April 11th, 2010
Written by Marcus de la fleur

I got freaked out pretty badly in the open plan review meeting over the code-required water service upgrade from 1 inch to 1 ½ inch, mainly because of the additional $10k to $15k price tag.

Once I got over the initial shock, I asked the plumbing reviewer what options I would have if I didn’t want to upgrade. Asking doesn’t hurt, right? To my surprise, I was presented with the following option (I paraphrase):

“If you can get a code variance letter from the commissioner of the Department of Water Management (DWM) saying that they are OK with the existing 1 inch water service, then we will be OK with it.”

I felt much better already, even though I had no clue to what my chances were to actually get that code variance.

The next logical step was to get on the phone with the plumbing inspectors at the DWM to present my case. I explained that we have applied for a green permit, that we are rehabilitating a three unit building and that we have plans for exceptional water management with all the low flow fixtures.

I was delighted to notice that the inspector was actually willing to evaluate if the 1 inch service line would suffice for the project. He asked for the plans and product information on all fixtures, which I e-mailed him right away.

Based on this information, the plumbing inspector added up all fixtures and developed a worst-case scenario. It is basically a calculation of how many gallons per minute (gpm) are needed at peak use and whether the existing 1 inch water service can deliver that amount.

More good news! It appears that the existing 1 inch service must do the job, because I was asked to submit a formal letter in which I applied for the variance. My case was presented to the commissioner and I received the variance approval shortly thereafter.

I took the letter back into another open plan review meeting, in which I received the missing final sign-off for the plumbing. All plans and documents went back to our green permit project manager who issued the permit a couple of days later. It was time to celebrate – and we did!

The water service issue added another two week delay to the green permit process and made me jump through a few more hoops (thank God I am somewhat fit!). It also saved us $10k to $15k, which we had not included in the budget. Plus, the green permit means we had no permit fees. Not such a bad deal after all!

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Permit - open plan review

Thursday, April 8th, 2010
Written by Marcus de la fleur

A lot of people, like me, feel somewhat inconvenienced by the building permit process and the associated bureaucracy. Some of the code requirements seem excessive and expensive. Other code requirements stand in the way of sustainable technologies. On top of it, not many people like to be told what they can and cannot do.

After our recent electrical incident, my attitude began to change. The ultimate goal for all the nagging on rules and building code regulations is to assure the public’s health, safety and welfare – to prevent life threatening incidents like we just encountered.  I am now rather grateful for that.

While our project was still in zoning, we received comments from the plan review and had a week to implement the necessary corrections. Following that week we had our first open plan review meeting – yes, I said first, because we had to return a few times.

Five building disciplines review the plans and commented:

  1. Electrical,
  2. Architectural,
  3. Ventilation,
  4. Structural, and
  5. Plumbing.

We had no comments from the electrical review. The few corrections we had regarding the architectural review passed in the first open plan review.

Ventilation was more complicated. The comments we received were easily addressed and passed, but a whole bunch of other issues cropped up during the open plan review. They mainly had to do with inconsistencies between the added third unit in the basement, the architectural plan sheets and mechanical plan sheets. We were given the chance to take care of the corrections during the meeting and finally received the ventilation sign off.

Then structural, for which we had a lot of comments and corrections. Since the porch collapse here in Chicago a few years ago, the requirements and reviews have become much more stringent.

Despite all the corrections, the open plan review did not go well. Our architect, who did the engineering for the back porch replacement, was not familiar with the new requirements and had a lot more work to do. I also needed to provide more information on the load bearing columns in the basement and the planned solar panels on the roof. We had to return a week later, made a few more corrections  and finally got the structural sign off.

We also had a lot of plumbing corrections. But it boiled down to three comments that presented major obstacles.

Our storm sewer that connects to the roof downspout runs through the building. Chicago plumbing code requires that the storm sewer is run as a separate line and only can be connected to the sanitary sewer immediately before it exits the building (Chapter 18-29-1104.2). This means that we have to add another 70 feet of cast iron soil pipe, which will cost us a buck or two.

We will have to add a pressure booster system to our incoming water main (Chapter 18-29-604.7). The city’s old water mains are mostly cast iron compared to ductile iron that is commonly used in the suburbs. Ductile iron can take much more pressure. That is why a lot of household in the burbs have a pressure reducing valve. We, on the other hand, need to boost the pressure in the building to assure adequate water supply up to the second floor – says the building code.

The real kicker was, though, that we are required to upgrade our incoming 1 inch water service to 1 ½ inch (Chapter 18-29-604.7). This carries a price tag of $10,000 to $15,000 alone. Something we had not put in our budget, and something that completely freaked me out!

Our existing 1 inch water service is a relatively new copper line with a shut-off valve and meter vault in the parkway. It should last another hundred years! Plus we have planned for all sorts of water conservation measures in the building, such as low flow fixtures.

Common sense tells me that the 1 inch water service should suffice for our three units considering all the low flow fixtures. But there are no provisions in the code that take water conservation measures into account. It looks like we are stuck with the code required upgrade and the associated price tag.

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Seasonal High Water Table

Sunday, April 4th, 2010
Written by Marcus de la fleur

The recent snow melt, followed by some good rains, have saturated our soils like it does almost every spring. This is a good time to check for a seasonal high water table (SHWT), and if there is one, for its elevation.

Like the name suggests, this is a seasonal occurrence, creating a soil zone of intermittent saturation. A SHWT may also occur after prolonged periods of very heavy precipitation.

At our previous pilot project in Elmhurst, the elevation of the SHWT was relatively high. Whoever built that house at around 1900 knew exactly where that elevation was, and made sure that the basement floor was above it.

Was this smart or a necessity? Probably both because pumping, like a sump pump, may not have been an option at the time, or may have been very expensive.

Fast forward to post-World War Two construction. Sump pumps became available and the design principle of keeping the basement floor up and above in the dry fell off the radar. Almost all of our neighbors in Elmhurst had deeper basements with sump pumps. And with it comes the energy consumption, maintenance, and worries about power outages.

The timing of all the excavation work in our basement was good. I dug one hole for what I thought would be an ejector pit. At the time of digging the bottom was almost dry. That changed as soon as the snow started melting and the rains kicked in.

ground-water-01

The water kept rising over a number of weeks until it hit an elevation of 27 inches under the basement floor. It was a huge relief knowing that our basement floor is a safe distance from the SHWT and that we won’t need a sump, at least not for this purpose.

ground-water-02

But it also keeps me worrying. This is a lot of water close enough to the basement to present serious moisture problems. I am sure glad that we have plans for a vapor barrier under the new basement floor. This will significantly reduce the risk of excess moisture.

I am also glad to have plans for the perimeter drain, but are wondering how much it will really help to keep the foundation wall dry. Because I don’t have a capillary break between the footing and the foundation, I leave a passage for that water to move up.

What will help is to keep the foundation wall exposed in the basement to let it dry out. Covering it up with insulation and drywall would trap the moisture and cause mold growth. I’d rather insulate the foundation wall from the outside.

I will also have to make sure that the basement is very well ventilated to remove any excess moisture and subsequent humidity. Just opening the windows won’t cut it. It may still be too cold in early spring to do so. What is needed here is mechanical ventilation.

I still wish I could somehow introduce a capillary break between the footing and the foundation…

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Perimeter drain preparations

Wednesday, March 31st, 2010
Written by Marcus de la fleur

I am done with one basement excavation project only to find that three others popped up. We have dug up the existing sewer lines and also removed 4 to 6 inches of clay from the basement to have sufficient depth for the new basement floor assembly. If you look at that assembly cross section, you will notice the interior perimeter drain.

basement-floor-07

The idea is that this perimeter drain will help with the moisture management of the existing limestone foundation wall. The dryer I keep the footing and bottom of the foundation wall, the less moisture there is to move upward.

That perimeter drain will be a perforated drain pipe. All perforated drain pipes should have a minimum slope to them, say 1% or a 1 foot drop over 100 foot distance – at least in my world as a landscape architect.

That means that the perforated drain pipe will be 12 inches lower at the south end of the basement than the north end of the basement. This could be a problem because I don’t want to excavate any lower than the bottom of the footing. We weren’t sure if we had enough footing depth for the new floor assembly.

basement-floor-10

It turned out we had – and it turns out that we also have enough depth for the perimeter drain with a 1% slope. So – I am back on the job excavating.

foundation-drain-001 foundation-drain-002

A lot of the green building practices are devoted to improving indoor air quality (IAQ) and providing good moisture management strategies. IAQ and moisture management are often directly connected to each other.

Good moisture management in and around a foundation wall and footing adds to the longevity of a building and improves the IAQ by reducing the risk of damp spots and mold potential. Well executed new construction has a capillary break (damp proofing or a membrane) between the footing and foundation wall.

foundation-drain-003

This capillary break prevents water from wicking up from the footing. Because I don’t have the luxury of such a capillary break on my old limestone footing I have an added incentive to keep the footing and bottom of the foundation wall as dry as possible.

Read more on foundation drains and moisture management

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Counting pathogens

Wednesday, 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!

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What happened to ‘Green’

Tuesday, 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!

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