| water filtration / treatment in / around montreal usine Des Baillets Ville Lasalle, |
|||||||||
 |
|||||||||
| filtration in montreal. Second largest filtration plant in Canada (Atwater being the first), is the most recent (built in 1978) of the 2 plants owned and operated by Ville de Montréal.
capacity: 1 136 000 m3 drinking water / day (Atwater: 1 364 000 m3 / day) Is located on the Aqueduc de Montreal (as is Atwater) but its primary water source is the St-Laurent river. Is automated and controlled by 1 main computer - only one person to supervise the process. |
|||||||||
 |
|||||||||
 |
|||||||||
| 1- water intake. | |||||||||
 |
the water is first grossly filtered upon intake to remove large objects.
It is then pumped to a height of 17 meters, the highest point in the process. The process at Des Baillets depends on gravity from this point on. the three images are of the different levels - the pumps base, the upper part of the pump and the water outlet into the channel which leads it to the rest of the plant. |
||||||||
 |
|||||||||
 |
|||||||||
| the relationship of the spaces | |||||||||
 |
|||||||||
| 2- filtration beds; the filtration gallery | |||||||||
 |
|||||||||
| main filtration step of the process. the water arrives from the intake in a covered channel and cascades into the basins. it then slowly seeps through a 1.5m bed of sand, which purifies the water of 85% of all particles (including bacterias and viruses...)
Underneath the upper deck of the filtration gallery is a servicing deck which allows maintenance access to the different valves. the water collected underneath the sand bed is piped into these spaces. the pipes take it to the ozoning. |
|||||||||
 |
|||||||||
 |
|||||||||
| the relationship of the spaces | |||||||||
| 3 - ozonation: disinfection | |||||||||
| ozone is a powerful non-toxic disinfectant which eliminates all remaining micro-organisms from the water. it is created in the tanks by using oxigen and electrodes, and sent to the level beneath, in which is the ozonation chamber, where it is mixed into the water. the ozone collects at the top of the chamber and must be burnt in a combustion chamber. This treatment is considered a relatively new technology (was installed in 1978!), which does not occur at Atwater. |
|||||||||
 |
|||||||||
| 4 - purified water collection basin | |||||||||
| the water is then collected into a reservoir. at Des Baillets it is located underground as shown in the isometric diagram. I was told that this space ressembles a cathedral and is seldom accessed by people. About once a year, it is inspected by a team in a canoe. | |||||||||
| 5 - chloration | |||||||||
| chlore is added to the water not to disinfect it, but to maintain the cleanliness of the water throughout the aqueduct once it is pumped out of the plant. | |||||||||
| 6 - pumped out | |||||||||
| the water is then pumped out into water mains which conduct the water to the city reservoirs. | |||||||||
| other spaces of interest.... | |||||||||
| the main corridor from the administration building to the filter gallery | |||||||||
 |
|||||||||
 |
|||||||||
| offices around a core in the administration tower.
in the tower also: 2 floors of labs (to monitor the quality of the water), and a board and presentation room |
|||||||||
 |
|||||||||
| the plant controller - the computer that controls everything. there is only one controller on duty at once. there are 5 controllers which relay each other, 24 hours a day, 7 days a week. | |||||||||
| also: other spaces include a large kitchen with a dining area, a metal workshop, an electrical and mechanical workshop, and offices for the electrical, mechanical and equipment contre-maitre and crew. Each team is composed of 8 to 10 members, which work at the plant 4 days/week. | |||||||||
| facts of interest: - the main water intake is in the S-Laurent river (not in the aqueduct as one might think) and installations have been made to insure that the water will not freeze at the intake during the winter. Since the beginning of operation of the plant in 1978, these installations have been used twice. - the aqueduct is not directly connected to the St-Laurent river as one might expect, but is fed by pipes from the same intake as Des Baillets. - "Mise à normes 2002": in 2002 the Ministère de l'environnement issued an exhaustive set of regulations to control the production and the quality of drinking water in the province (for info: website of ministère de l'environnement). By 2007, all facilities must respect these regulations. At Des Baillets, the turbidity (particles in suspension which cause the water to be more or less opaque) of the raw intake water before filtration beds is mainly concerned by these regulations. It is likely that a full chemical treatment will be introduced, but Mr. Raulin hopes that U.V. treatment, a new, more efficient and possibly safer will be introduced. |
|||||||||
| what is good about Des Baillets. The administration area, contained in a tower at the front of the building, receives a lot of natural light, and the extensive glazing allows for breath-taking distant views from almost any point in the building. There is also a care for detail in the exterior enveloppe of the facility.
The circulation of the water in the facility follows gravity, which is natural and logical. The filtration gallery also made a strong impression; narrow, tall and sparse slits of light along the walls, allowing for a controlled amount of natural light, which danced on the water contained in the filtration bassins. The facility was conceived with more space than needed to allow for expansion in order to avoid the type of remedial and un-efficient expansion which has taken place at the Atwater plant. To this day, most of this space has not been called to serve, and the staff has set up a tennis court (!!!) in one of the spaces. what is not so good about Des Baillets. The logic of the overall planning of the facility appears in no way related to the order of the functions contained (see aerial picture). The landscape has not been addressed more than planting grass around the facility, and as close as it is to the residential neighborhood, its servicing yard faces the residential area, and the entire facility is surrounded by a chain link fence to keep people out of the property. The enigmatic volumes do not express the goings on inside, and seem to be devised to intimidate and repulse. Spaces for the maintenance staff are deprived of natural light, and the sharing of space between the electrical, mechanical and equipment teams causes friction. |
|||||||||
| image sources: Ville de Montréal.Usine de Filtration Charles-J. Des Baillets. brochure Ville de Montréal. L'eau, Une Source Indispensable à la Vie. brochure photos of the interior by myself. |
|||||||||