Ice is blocking intake at Pittsburgh Water's treatment plant on the Allegheny River.

In an update around 11:30 a.m. on Tuesday, the city said crews have successfully broken up some of the ice formation on the river. A barge and tugboat are en route to help. 

Authorities said the blockage may impact water pressure and service, especially in higher elevation neighborhoods. But so far, service has remained uninterrupted and pumping capacity has improved, the city said. 

In the meantime, leaders are monitoring water levels at Pittsburgh Water's storage tanks. Pittsburgh Mayor Corey O'Connor posted photos to social media, saying he's at the treatment plant to monitor the situation. 

This is a developing story. Check back for updates.