18 October 2024

40NetZERO

Shifting gears to the eastern tip of the island of Montreal, developer 40NetZERO is also planning and preparing for the impact of climate change. Project leaders of one of the largest projects of its kind were diligently monitoring the storms as they happened. With much delight, when asked how their new building faired in the storms of July and August, 40NetZERO Director and Coordinator Julie Larocque replied, “All systems in place adequately did their work! Water flowed in its intended direction and did not accumulate in the interior of the building. Exterior pooling happened exactly where it was supposed too, not affecting the building!”

Julie Larocque
40NetZERO

Designers for the multi-phased project planned the street and Building A (Phase1) with filtering ditches/infiltration gardens to be installed on both sides of the street, as well as in the building’s parking lot. Underground retention basins, open-air grassed basins and the oversizing of certain pipes were planned to accumulate water. Flow regulators were added to control and, above all, limit rapid discharge into the municipal sewer system. The installation of flow-controlled drains on the roof of the building is also part of the measures implemented.

40NetZERO is doing things differently in terms of traditional rainwater management. All water from socalled normal rainfall events is returned 100 percent to the water table via the filtering channels, without ever passing through the municipal network. When major rainfall events happen, that is those that do not allow water to be completely returned to the water table, the water is accumulated in designated areas (retention basins, oversized pipes) so that the developer can control its discharge into the municipal network to avoid further clogging it. This discharge is limited to a very low flow , almost 4 times less than the total flow normally generated.

40NetZERO says that it is a project that features a much higher percentage of permeable surfaces (lawns, planting areas, etc.) than is usual elsewhere in the same type of development. In all, around 20 percent of the total surface area of their Industrial campus will be considered green, that is permeable. This will undoubtedly help reduce the amount of water drained into the sewage system.

Finally, the building’s roof has been designed to the FM Global 90 standard, a standard that is the world leader in measuring quality. This rating means their roof is highly resistant to bad weather and strong winds. It is therefore capable of withstanding heavy rainfall without suffering structural damage. This reduces the risk of leaks and ensures that water will be directed towards drains rather than to the roof membrane.

When asked what forward thinking 40NetZERO has for stormwater management, Larocque is of the opinion that measures proposed by their designers and built to date have proved their worth and contribute to effective, healthy stormwater management. “We will undoubtedly continue to include these elements in future developments, as well as incorporating others elsewhere on the site (e.g. permeable paving areas, honeycomb paving zones, etc.) We believe that each and every one of us has become even more aware this summer of the devastating scale of the consequences caused by climate change. We therefore make it our duty to do our part and to continue our efforts and reflections in the constant search for new measures and/or new innovations that we could integrate into the 40NetZERO development with a view to further promoting sound stormwater management,” she pointed out.

It is without a doubt that the impact of recent severe weather has had developpers and building experts rethink how buildings and sites are developped. Working closely with municipalities, engineers and insurance experts, developpers are finding new solutions to new problems. Hopefully, many of the systems these developers are putting in place will be overkill, however judging from past history, the battle to find a solution to “stop the rain” lives on.

Rosefellow Candiac
Green roof