A man was hit by lightning and killed during Tuesday night's violent thunderstorm in Toronto.

Witnesses said the 29-year-old man was struck while taking shelter under a tree at Christie Pits in central Toronto at about 8 p.m.

An autopsy will be performed on Wednesday. Christie Pits is a popular park that has soccer fields for kids, a pool and a baseball diamond.

The lightning strike was one of at least 430 reported in the city during the storm, which also dumped dozens of millimetres of rain in a short time.

The sudden deluge caused raw sewage to spill along the waterfront near Parkside Drive and Lakeshore Boulevard West.

Lou Di Gironimo, the city's general manager responsible for the water system, said the sewer pipes couldn't handle all the extra water dumped during the storm and the overflow caused a concrete sewage hatch to burst.

"The old sewer systems that we have, the combined systems handled both sanitary flows and rain flows in one pipe. In this event when we have too much rain it's designed to bypass so we don't flood homes. It is now discharged out into the park area," said Di Gironimo.

The spills were contained to a playground area, and Di Gironimo said crews are assessing other areas to make sure the sewage hasn't spread.