The Engineering Division is monitoring lake levels and the potential to flood year round. To keep people informed, we’re sharing a weekly update with you, and as frequently as needed, should a major rain event happen. We are not sending these to elevate concern, this is just a new communication option for us to keep you informed as flooding deeply impacted our community last summer, and may be top of mind when rain moves through our area.
July 12, 2019 Update
We experience no significant additional flood risk due to the current lake levels, Lake Monona is dropping slowly. The forecast is hot with no rain until mid-next week, so we are trending in the correct direction.
Recall typically 1” of rain in the Mendota watershed gets you a 3” rise in the elevation of Lake Mendota.
Lake Mendota Today
Elevation = 850.74 feet
Change from one week ago = down 0.07 feet
Change from one month ago = up .54 feet
Above/below summer maximum: by .64 feet
Above or below 100 year elevation below 2.6 feet
Lake Mendota Statistics
Surface Area = 9,842 surface area acres
Summer Min = 849.6 feet
Summer Max = 850.1 feet
100-Year Record = 852.8 feet
Lake Monona Today
Elevation = 846.52 feet
Change from one week ago = down 0.14 feet
Change from one month ago = up 0.53 feet
Above/below summer maximum: above by 1.32 feet
Above or below 100 year elevation: down 1.18 feet
Lake Monona Statistics
Surface Area = 3,274 surface area acres
Summer Min = 844.7 feet
Summer Max = 845.2 feet
100-Year Record = 847.7 feet
The problem low ground elevations in the Isthmus area are at about elevation 848.5 to 849.00.These areas drain to Lake Monona, or the Yahara River downstream of the Tenney Locks. The closer Monona rises to 847.00, the more ineffective our drainage system in these low areas becomes.