Water Treatment Plant – New Delhi
A new $13 million wastewater treatment plant is being built in the community of Delhi in Norfolk County, Ont. Some people describe it as a ‘fine balancing act’. The plant is built as a result from the coordination between the Stone Town Construction Ltd. contractor and the plant operators as to have access to the existing work and operate properly.
Looking back, in 2012, Norfolk County asked the consulting firm for a feasibility study on a potential upgrade for the plant’s construction. To carry out the project, many things have to be undertaken. Amongst them being the construction of an access road for equipment, a chlorine demolition chamber and a considerable dewatering of the site. At the beginning, there were both operational and maintenance problems, such as an odors issue.
The plant is especially designed to accommodate “post disaster” standards, allowing it to resist a once in 50-year earthquake without any damage. David Evans, associate director, R.V. Anderson Associates Limited, says that the plant is one of the county’s most expensive infrastructure projects in decades and has steel reinforcement in the masonry block walls. According to him, the planning and design process for the construction is also a balancing act.
“It is composed of six tanks, a headwork building with odor control, a primary pump house building, a blower/electrical/chemical building and a pipe access tunnel. It is built immediately in the south side of the old 1947 plant which has to keep operating during the construction which started last November and won’t wrap up until 2015,” Evans says.
The high water table influenced the design and construction of the six steel-reinforced concrete tanks which comprises the bulk of the facility. In high ground water areas, a sewage tank has the potential to float in case it’s empty. The same is true for repairs and maintenance. The tanks have 600-mm-thick slabs – very thick – being attached to 12-meter-deep steel piles in order to prevent such floatation. They also have oversized toes providing lateral support to hold them down. And to tackle the tight constraints, Stone Work Construction divided the plant footprint into three sections. For the time being, the contractor is concurrently erecting the west and east halves with the use of two cranes in a space as wide as 15 meters where the center section will be built.
Norfolk County provides the needs and requirements for water and wastewater infrastructure throughout the various communities within the County over a 20-year planning period to 2027. In addition to a new plant, a pumping station will have to be built as well.