[Mick]

RESSW.pdf (ca.gov)

I've been monitoring water levels on the CDEC site for over 10 years.  I started doing this when I noticed the spectacular claims in the media were separated from reality.  

% of Capacity at this time of the year is interesting, but less important than % of Average for this date.  I have added those percentages to Mick's table (shown in red).  Keep in mind that when the snow pack starts to melt the high elevation reservoirs will fill up rapidly and put pressure on the downstream reservoirs.  Folsom, the state's 10 largest reservoir is a good example of this type of reservoir - it is at 404 feet above sea level.  It's purpose is to catch the snow melt and the massive amount of water flowing through the American river to prevent the historical flooding of the Sacramento basin.  Trinity is higher up at 2200 feet.  It is mostly filled with snow melt.  That is why it is at a low level of capacity in early January.

In 2017 the spillways of Oroville Dam failed and almost inundated Oroville.  it cost $1 billion to repair the damage.  In 2017 I started warning people that Oroville was filling up too fast - 3 weeks before the spillway failed.  At the rate Oroville was filling there was no way to release enough water fast enough.  They should have started earlier in the year.   For smaller reservoirs nearing or exceeding capacity is not such a big deal.  They can release a high % of their storage very quickly.  Oroville is a different story.  It is the second largest reservoir in California after Shasta with a capacity of 3.5 million acre fee.  That's 1.152 TRILLION gallons.

I have a fancy excel spreadsheet that I have crafted over the years with colorful conditional logic and macros.  I am quite proud of the output because you can tell at a glance where the system might be in trouble (over/under average and capacity).  I would post an image, but apparently you can't do it on this site.

As of this evening, the top 20 reservoirs were at 47% of Capacity and 81% of Average. My bet is that 100% of average will be exceeded in a few days.

Using threepointer's scale:  % of Average shown in red  after % of Capacity.

Large (1 MM+ AF)
Oroville, 58% / 105%
Shasta, 53% / 84%
Pine Flat, 48% 126%
San Luis, 46% / 67%.
New Melones, 38% / 67%
Trinity, 30% / 48%
Don Pedro, 75% / 108%
New Exchequer/Lake McClure 56% / 122%
Berryessa, 65% / 85%
Almanor, 63% / 102%

Medium (400k - 999k AF)
Folsom, 55% / 126% 
New Bullards, 80% / 125%
Diamond Valley, 61% / 84%
Friant, 83% / 148%
Isabella, 19% / 71%
Camanche, 75% / 124%

Local Reservoirs (and of local interest)
Hetch Hetchy, 81% / 125%
Lexington, 101% / 242% (not a typo)
Stevens Creek, 70% / NA 
Lower Crystal Springs, NA / NA
San Andreas, 93% / 114% 
Uvas, 102% / NA
Clifton Court Forebay, 56%.

[Mick]

RESSW.pdf (ca.gov)

I've been monitoring water levels on the CDEC site for over 10 years.  I started doing this when I noticed the spectacular claims in the media were separated from reality.  

% of Capacity at this time of the year is interesting, but less important than % of Average for this date.  I have added those percentages to Mick's table (shown in red).  Keep in mind that when the snow pack starts to melt the high elevation reservoirs will fill up rapidly and put pressure on the downstream reservoirs.  Folsom, the state's 10 largest reservoir is a good example of this type of reservoir - it is at 404 feet above sea level.  It's purpose is to catch the snow melt and the massive amount of water flowing through the American river to prevent the historical flooding of the Sacramento basin.  Trinity is higher up at 2200 feet.  It is mostly filled with snow melt.  That is why it is at a low level of capacity in early January.

In 2017 the spillways of Oroville Dam failed and almost inundated Oroville.  it cost $1 billion to repair the damage.  In 2017 I started warning people that Oroville was filling up too fast - 3 weeks before the spillway failed.  At the rate Oroville was filling there was no way to release enough water fast enough.  They should have started earlier in the year.   For smaller reservoirs nearing or exceeding capacity is not such a big deal.  They can release a high % of their storage very quickly.  Oroville is a different story.  It is the second largest reservoir in California after Shasta with a capacity of 3.5 million acre fee.  That's 1.152 TRILLION gallons.

I have a fancy excel spreadsheet that I have crafted over the years with colorful conditional logic and macros.  I am quite proud of the output because you can tell at a glance where the system might be in trouble (over/under average and capacity).  I would post an image, but apparently you can't do it on this site.

As of this evening, the top 20 reservoirs were at 47% of Capacity and 81% of Average. My bet is that 100% of average will be exceeded in a few days.

Using threepointer's scale:  % of Average shown in red  after % of Capacity.

Large (1 MM+ AF)
Oroville, 58% / 105%
Shasta, 53% / 84%
Pine Flat, 48% 126%
San Luis, 46% / 67%.
New Melones, 38% / 67%
Trinity, 30% / 48%
Don Pedro, 75% / 108%
New Exchequer/Lake McClure 56% / 122%
Berryessa, 65% / 85%
Almanor, 63% / 102%

Medium (400k - 999k AF)
Folsom, 55% / 126% 
New Bullards, 80% / 125%
Diamond Valley, 61% / 84%
Friant, 83% / 148%
Isabella, 19% / 71%
Camanche, 75% / 124%

Local Reservoirs (and of local interest)
Hetch Hetchy, 81% / 125%
Lexington, 101% / 242% (not a typo)
Stevens Creek, 70% / NA 
Lower Crystal Springs, NA / NA
San Andreas, 93% / 114% 
Uvas, 102% / NA
Clifton Court Forebay, 56%.