• Feet Down - This is the number of feet the surface is down from the maximum fill level. So if the lake is totally full, the "feet down" is 0.
• This / Previous "Season" - The data is transformed to be from Nov to Oct. So one "season" might be Nov 2019 to Oct 2020. This is because the lake usually bottoms out at the end of a "season" in October.
• Confidence Intervals
• 100% - All measurements fall in this range. (So this is basically the min and max at each date.)
• 90% - 90% of all measurements fall in this range.
• 50% - 50% of all measurements fall in this range.
• Median - This is the median lake level. That means that 50% of the observations are above this value. And 50% are below.

This shows the how fast the lake level is changing (vertically) in inches per day, like the next chart. But here I calculate a 4 week moving average, which smooths out the curve.

This shows confidence intervals as well. See the note in the firt chart ("Highest Level") for an explanation.

This shows the how fast the lake level is changing (vertically) in inches per day.

I do not show confidence intervals for this chart because daily changes are so variable the ranges don't mean much. See the previous chart for better smoothing.

• Max - the maximum lake fill level for a given year. In a good year the lake fills almost to the top.
• Min - the lowest point the lake gets to for a given year, after the summer drawdown.

• This shows the full data over the last 20 years.
• The longer the time period, the harder to read, so I'm limiting to 20 years.

• This is a histogram showing when the lake reaches its lowest level each year.
• October is generally the low point for the year, after the summer drawdown, and before the winter rains.
• When you see January, that probably means that last year's lowpoint is lower than the normal October drawdown low for the current year.

• These charts are histograms of the lowest and highest levels for each year.
• The highest level is usually close to full — most years the lake nearly fills.
• The lowest level has a much wider spread: some years the lake barely draws down, others it drops a long way.

• This shows the full data over the full range, yearly.
• The yellow is summer - Memorial Day to Labor Day
• Y-axis is feetdown
• X-axis is month: Jan (1) to Dec (12)