Sanitary System:
The sanitary system consists of drainage and venting system.
The venting system allows the sanitary waste to have access to atmosphere pressure and to be drained by gravity. Venting system also protects the sanitary system against accumulation of biogas which could be hazardous.
The sanitary drainage works based on natural gravity and in some cases the sanitary pump is required to pump the sewage to the city sanitary manholes.
The sanitary drainage pipes in old buildings are usually Clay pipe or Cast iron and they can last for more than 50 years. In newer buildings the sewer pipes are made of either PVC or ABS, which provide a smoother surface draining higher amount of sewage. The service life of PVC and ABS pipes are more than 70 years.
The sanitary system design varies based on the type and size of the building and each city has slightly different by-laws based on the capacity of their existing main sanitary lines, and the capacity of the waste processing plants.
Storm System:
The storm system gathers and drains the rain water from the roof and any other hard surface areas into the city storm lines.
The storm system pipe sizing and design depend on a few factors such as rainfall density in the municipality at peak season and the slope of the hard surface receiving the rain water.
The collected rain water needs to be filter for silt and other deposits in a manhole before being drained into the city storm line. The PVC pipes are usually used for horizontal and vertical storm pipes. The underground rain water could also be gathered by perimeter storm system using perforated PVC pipes. These pipes can last for more than 50 years although the exposure to high UV rays could reduce this service life.
We have designed sanitary and storm systems in different municipalities in lower mainland for new and retrofit projects ranging from small multi-family building (triplex) in north Vancouver to commercial and motel building in Mission.
