The annual chlorine flush of the water system in Midland begins today and is expected to last all month long.

According to NewsWest 9, discoloration of the water and a strong chlorine smell are some of the possibilities residents of Midland could experience.

The flush is necessary to keep biofilm from increasing during the summer months. Biofilm is a slimy layer of bacteria that forms on pipes naturally during warmer months of the year.

The flush will help clean out the biofilm and keep the lines clear for another year.

The city said some residents may not even notice any change in their water during the flush, which will last all month.