The water level at Tahoe is passing the test this year. However the latest report card for the lake is not as clear.

"The grade is an incomplete because the story is constantly changing," said Geoffrey Schladow of UC Davis Tahoe Environmental Research Center. 

It's hard to predict where Tahoe will be in a year. After all, who would have thought we'd get so much snow in 2017. Next year's notes might be different too, considering the report goes through December and the Sierra was still a winter wonderland this past January. 

"It was above the rim at the end of December but then you see this sudden rise as we get all this snow," said Schladow. 

The new snow we got only accounts for about one percent of the water in Tahoe. The temperature is pretty cold, but over the past four years the water temperature has risen about one forth of a degree each year. 

"Overall the lake is warming and that's creating an environment that's more suited for many invasive species," added Schladow. 

Algae is not only connected to water temperature but they are also connected to the clarity of the water. On the plus side, winter 2016 data shows the clarity improved by nearly 12 feet. This proves new storm water projects are working. Trees are struggling though.

"As they die they're less effective and binding to the soil. So one thing is looking for erosion now," said Schladow. 

Next years report card will be an interesting one.

"We have a really good idea now of what happens during a recent drought. And now we're going to see what's going to happen during a recent snow year," said Schladow.

He's not sure when he'll be able to give Tahoe an actual grade, but if there was a fire or something it would obviously be poor.