Extreme weather is becoming more common. But there are ways for municipalities to adapt

Newfoundland and Labrador municipalities can't stop the impact of climate change, but two climate action consultants say more can be done prepare for extreme weather events.

St. John's city crews scrambled this week to repair flood and erosion damage after three days of record rainfall from post-tropical storm Earl. As of Wednesday, four roads were still closed for repairs.

Jess Puddister, a scientist and climate action consultant, said watching the damage play out was "frustrating."

"We're continuing to develop in the same way that we have the last number of decades and we know that that development style does not build resilience to flooding like we've seen over the last couple days," she said.

Puddister said low-density, high-elevation developments with large areas of non-permeable surfaces, such as pavement,exacerbate potential floods. Without localized water retention, water instead gets directed into drains, pipes, and eventually into other bodies of water.

"When we go into an area and we strip it of all the natural vegetation and we pave large areas of the land, that's eventually just directing more and more water into our river systems that were not created to handle those volumes," she said.

In St. John's, bodies of water like the Waterford River and Rennie's River often flood after rain storms.

The watershed approach

Puddister said municipalities should take a "watershed approach" to development.

"We really need to be looking at watershed modelling and thinking about how does water behave? How does it move? Where is it going to go? And what is development that's taking place upstream?"

Engineer and civil planner Ashley Smith is the managing director of Fundamental Inc., a consulting agency that helps municipalities adapt to and mitigate the impact of climate change.

Smith said Fundamental Inc. develops watershed models, which can help municipalities assess the short- and long-term impact of rain, storm surges and runoff on current and future development.

"You can start to then use the detailed watershed model to adjust how you're allowing planning and development," she said.

Smith said increasing permeability where possible meaning swapping pavement and concrete for permeable surfaces like vegetation and increasing urban density in future developments are two ways to mitigate the impact of future extreme weather events.

"It's not meant to be like anti-development, it's meant to be strategic development, because it would be no good if the town allowed development in a space that then caused flooding in an existing community," she said.

Adaptation and mitigation

Two municipal leaders say they're already making efforts to mitigate the impact of climate change.

St. John's Coun. Sandy Hickman said storms like Earl are not uncommon anymore, and the city is adapting.

"The city has change its thinking. It's opened up bridges, larger culverts, things like that," he said.

Mount Pearl Mayor Dave Aker said the city didn't sustain much damage fromlast weekend's rainbut council is prepared for more frequent rain events.

He said the city has remodelled its flood mapping in the Waterford Valley and takes climate change into consideration when it replaces infrastructure.

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