An environmental economist says it's time to weatherproof Ottawa's budget in the face of climate change, as the city grapples with a projected $11-million deficit for 2017.

The red ink was precipitated in part by record rainfall, flooding and heavy snowstorms.

Ram Sahi, a former Carleton University professor, said massive swings in the amount of snow and rain caused by climate change will make it difficult for cities to know how much money to set aside for snow removal, flood cleanup and other weather-related costs.

"It will be quite a challenge because global warming and climate change doesn't have an equal impact on all cities," he said. "The forecasting of the impact becomes a lot more difficult."

Nearly $8 million of the city's projected deficit is attributed to people using less water this spring thanks to heavy rains.

In other words, there were so few sunny days that people weren't watering their lawns or filling their pools very often, taking a big chunk out of the city's anticipated revenues.

The city also had to pay more overtime this year to workers plowing roads in the wake of major snowstorms. This winter was 12 per cent more severe than the five-year average according to the city's calculations, which factor in snowfall, freezing rain amounts and freeze-thaw cycles.

Contingency fund for natural disasters

Sahi said cities should start building bigger buffers into their budgets to account for more extreme weather fluctuations.

He said the city also has to start budgeting more for natural disasters, which are likely to become both more frequent and more severe.

This year Ottawa spent $2 million in response to flooding along the Ottawa River which forced the evacuation of hundreds of homes.

"The policy should be to build infrastructure so that it becomes more adaptable, as well as have a contingency fund," he said.

The finance department looks at the most recent trends to account for fluctuating weather in the city's budget, according to Isabelle Jasmin, the city's deputy treasurer.

"We're looking at trends in climate change in terms of how it's impacted in previous years," said Jasmin,

Reserve Funds cover the costs

She said the city looks at five- and 20-year trends, but more recent data is more valuable.

"Twenty years ago probably isn't as reflective as where we're headed," Jasmin said.

Jasmin said the city has been able to cover weather-related deficits over the last few years with a combination of reserve funds and unused budgets from some departments.

City staff have recommended funding this year's gap in water revenues from a water and wastewater reserve fund.

Sahi said the financial impact of climate change will likely become easier to budget for in the future as more data becomes available.

City councillors will discuss the projected deficit for 2017 at a finance and economic development committee meeting on Sept. 5.