City of Regina officials say the large rainstorm on June 11 showed the need for further investment in the city's infrastructure.
Kim Onrait, executive director of citizen services, said the city got between 50 and 75 millimetres of rain from 7 a.m. to 9 a.m. CST.
"The city's operational team responded by ensuring pump stations were functioning properly, triaging flooding locations and closing roads to reduce the risk to the traveling public," Onrait said.
Fire and Protective Services also rescued several residents whose vehicles were submerged under the city's underpasses on Albert and Broad Street.
Onrait said the city is investing in infrastructure to reduce the impact of future storms, including a stormwater project in the North Central Neighbourhood to help prevent flooding during large storms, impacting 450 homes.
The cost for the neighbourhood is $15 million over three years and work is underway. The city has also spent more than $200 million on the wastewater treatment plant and McCarthy Boulevard pumping station in recent years, he said.
"Despite our quick response and our investments underground, the sewer system is not designed to handle that much rain in a short period of time and further upgrades are required," Onrait said.
As a result of the rain, wastewater was released into Wascana Creek, Kurtis Doney said. Doney is the director of water, waste and environment for the city. About one to two per cent of the total wastewater created during those two hours was released, he said.
Doney said it was very diluted because of the amount of rain and will have a minimal environmental impact.
"The Water Security Agency had been notified of this event and we are working with them to determine next steps in addition to the significant wastewater upgrades," Doney said.
The city plans to spend $165 million over the next five years to improve the stormwater and wastewater systems, Doney said. He said rainwater can get into the wastewater system through a few different avenues and improvements are needed.
"That's why we're seeing these large flows. So it's an ongoing program that needs to continue investment, to upgrade our stormwater system to allow the stormwater to go somewhere and upgrade the wastewater system to keep the wastewater flowing," Doney said.
The city is also investigating ways to reduce the amount of stormwater accumulating under the Albert Street underpass. Doney said they're looking at options and upgrades in the area, but there's not a lot of land available to store the stormwater.
The city received about 300 service requests about flooding, sewer backups and forestry concerns, Onrait said. The city said it hopes its 'adopt a drain campaign' also helps in the future. People can name a drain and then are responsible for clearing it in the event of a storm.
"We really look to the community to be out there before and after a rainstorm to remove any debris, to allow the rain to get to the storm drains," Onrait said. "We can't quantify the difference that it made, but we know there's many stories of residents clearing out storm drains."