Summer is a good time to smoke test sewers due to low flows and suitable weather.
Why do I want to smoke test my sewers? If you are getting complaints from residents about sewer backup into their basements, you already know one of the answers. The other reason is that USEPA (and, hence, state agencies) are increasingly “on the case” when it comes to untreated sanitary sewage overflows. If you haven’t already heard from them, it’s probably just a matter of time.
It’s not unusual for older sanitary sewer systems to have high flow rates during storms due to water entering through cracked pipes and gaps in manhole walls.
There are also all of the homes where, over the years, the owners have quietly connected downspouts and sump pump discharges to the sanitary sewer.
Smoke testing is generally intended to find:
• buildings that have illegal downspout, cellar, yard or foundation drain connections to the sanitary sewer
• illegal sump pump discharges into a sanitary sewer
• points of groundwater or surface water intrusion into sanitary sewers
• any cross connections between sanitary and storm sewers
Give it a try!
If you haven’t already tried smoke testing, it’s not difficult. The major investment is a smoke blower that costs between $900 and $1,500, depending on features. There are two options. You can use classic smoke candles or you can purchase a blower that utilizes the relatively newer liquid smoke technology. Each method has advantages and disadvantages as discussed in our catalog.
The absolute “must” for a smoke testing program is to explain to local residents:
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what you are doing
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why you are doing it
•
when you are going to do it
•
what is liable to happen when you do it
Prepare residents for smoke coming out of a basement floor drain or the eaves of a neighbor’s house. Don’t forget to notify the fire department of where and when you will be working.
Ideal smoke testing training comes from having an experienced person assist for the first day or two.
Many state Rural Water Associations have circuit riders or technicans that can facilitate training. Perhaps you can simply borrow an experienced worker from a neighboring town?
Unfortunately, we’re not aware of any books on smoke testing. However, we have published a pamphlet that should help you get started. Or, if you are already smoke testing, it may still give some helpful hints. You can download a copy here. If you need advice on equipment selection, call us at 800-548-1234 and ask for our Technical Support Department for other tips and techniques.
