Residents of a downtown apartment building will be allowed back into their building Thursday afternoon following a carbon monoxide and flooding scare.

Cold temperatures resulted in backup on the Bow River, causing ground water to seep into the parkade of the Marquis building on 6th Avenue and 11 Street S.W.

Efforts to pump the water out with gas-powered pumps caused a build up of carbon monoxide and residents were evacuated early Wednesday morning.

The building was aired out and carbon monoxide was no longer a threat Wednesday afternoon but officials said they were unable to let residents back in because water levels in the parkade continued to rise.

The apartment building will be open for residents at 1 p.m. today.