The numerous lake studies performed and documented by experts identify storm water runoff as the main cause of the water quality problem.
| Phosphorous inputs to the lake have increased by 66% in 10 years. |
| Deep water phosphorous has increased by 24%. |
| Phosphorous recycling by sediment has increased and caused eutrophication. |
| The rate of sedimentation buildup has been doubled by recent development in the watershed. |
| Pine Lake is now suffering from fall and winter algae blooms. |
Even as these problems have been mounting, King County urban planners rezoned the watershed as urban dense. This means there will even more intense development of homes and businesses producing ever increasing runoff into the lake.