MONONA, Wis. -- Monona residents are working to protect their homes by building sandbag walls.

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Along Pocahontas Drive in Belle Isle, residents have watched the water rise on Lake Monona since Monday.

But on Wednesday, the situation shifted suddenly when water was released out of Lake Mendota, causing Lake Monona water levels to go up.

Residents were busy filling bags with sand to build a wall along the waterline Wednesday. People with homes along the lake and neighboring channels said they are worried about the rising water.

Monona police said the water is above normal levels and in the danger zone.

Homeowners said they've been here before, but this time their concerns are growing.

"They're letting Mendota down, so obviously we're going to go up. So, we're concerned about that and we're also concerned about the rain," said homeowner Judy Wilson.

Residents who were filling sandbags Wednesday said they are frustrated because they thought they would be notified before dams on Lake Mendota were opened. But since they said that didn't happen, they had to rush home from work to build walls of sandbags.