Concrete Pipe Sanitary Sewers - To Clean or Not to Clean?
Concrete Pipe Sanitary Sewers - To Clean or Not to Clean?
(OP)
Our City has many sanitary sewers consisting of concrete pipes. This pipe material was commonly installed between approximately 1950 and 1970. As these concrete pipes age, hydrogen sulfide attacks the wall surface and deteriorates the pipe from the inside, mostly above the water line.
My question deals with maintenance of these older, deteriorating concrete pipes. Cleaning using a jetter (typically with a full-circle spray nozzle) is frequently warranted to remove grease and debris. Should we be jetting/cleaning these pipes? Does jetting/cleaning remove the deteriorated surface exposing the underlying concrete and accelerating the deterioration process; or does cleaning remove the acidic slime thereby slowing down the deterioration process?
So, in the interest of extending the life of a concrete pipe sanitary sewer, should we clean more frequently, less frequently or only when absolutely necessary?
My question deals with maintenance of these older, deteriorating concrete pipes. Cleaning using a jetter (typically with a full-circle spray nozzle) is frequently warranted to remove grease and debris. Should we be jetting/cleaning these pipes? Does jetting/cleaning remove the deteriorated surface exposing the underlying concrete and accelerating the deterioration process; or does cleaning remove the acidic slime thereby slowing down the deterioration process?
So, in the interest of extending the life of a concrete pipe sanitary sewer, should we clean more frequently, less frequently or only when absolutely necessary?





RE: Concrete Pipe Sanitary Sewers - To Clean or Not to Clean?
During the cleaning, deteriorated pieces of pipe are removed by the spray nozzle exposing fresh surfaces to the corrosive actions of the wastewater. Sulfide reducing bacteria and gases are also removed during cleaning. Probably a wash.
Too frequesnt cleaning will probably damage the concrete pipe, but who has money for that.
RE: Concrete Pipe Sanitary Sewers - To Clean or Not to Clean?
RE: Concrete Pipe Sanitary Sewers - To Clean or Not to Clean?
Inliner and Insituform are a couple of options
RE: Concrete Pipe Sanitary Sewers - To Clean or Not to Clean?
If you can't get the money, cvg is spot on as usual. I would think that the increased rate of deterioration due to jetting would be very small in comparison to the sulfide attack on the concrete pipes.
I haven't studied it, but I think that the grease and debris is not protecting the concrete from attack or enhancing the deterioration in any measurable sense.
RE: Concrete Pipe Sanitary Sewers - To Clean or Not to Clean?
RE: Concrete Pipe Sanitary Sewers - To Clean or Not to Clean?
Richard A. Cornelius, P.E.
WWW.amlinereast.com