Jurisdiction is a complicated topic with many actors involved.  Here's a breakdown.

Runoff - Rice Creek Watershed District is responsible for the water quality leading into Long Lake until it meets the lake itself.  Hence, they are interested in assisting with anything runoff related, such as rain gardens and shoreline buffers zones. 

Water Surface - The water surface is technically the responsibility of Ramsey County Sheriff's Water Patrol Unit, so any safety concerns should be routed to them (non emergency number is 651-490-4511 and 911 for emergencies).  LLIA contracts with New Brighton Police for the Lake Monitor.  

Lake Water - Lake water is the responsibility of the Minnesota Department of Natural Resources.  LLIA collaborates with the DNR on water quality issues and obtains permits for treatment.

Boat Landing - The landing is the responsibility of the City of New Brighton.  

Long Lake Regional Park - The park is owned by the county.  Since they are the owners of half the lake, LLIA collaborates with park administration in the efforts to maintain the goals of LLIA.  If you have any issues regarding the park, such as loud music at the pavilion or otherwise, please call 651-775-7594.