Ashokan EAST BASIN Temps

[JayBay]

Depth Ft.       Temp degrees F           Dissolved O2 (mg/L)
 10                      72                                  8.7
 32                      59                                  7.9
 72                      48                                  1.8
Have started drafting from the East so the pool elevation is going down, West Basin should start refilling.

[Gordon]

Thanks for the info, particularly O2 levels. Nice to see good levels at 32 ft., I bet #'s from most EOH reservoirs other than maybe Kensico and a few others would not look that healthy. Any idea why the West basin was drawn down so far while the East was relatively steady until very recently?

[brushwolf]

Interesting that the o2 level is less in the colder water. I would have thought it would be higher .

[JayBay]

The very bottom layer of water goes anoxic after awhile, I forget why, that's why earlier in the summer the trout were deep near the bottom while it still had oxygen, but now they are higher up in the thermocline seeking oxygen.  I think it's just that bottom layer sits there with no mixing and the oxygen goes out of it after awhile.  As far as west basin draw down - if the West basin water quality is good enough to deliver to the City through the aqueduct, it is always best to use west basin water to create a void in the basin so next spring during run-off, snow melt, and storms the incoming Esopus creek can fill the west basin and provide settlement until it clears up again while using the east basin reserve.

[JayBay]

WEST BASIN
Depth ft.]    Temp degrees F     Dissolved O2 mg/L
     10                        67                                9.1
     39                        58                                2.3
     91                        50                                4.4
     141                      49                                4.1
[/EAST BASINu]
     10                        69                                9.1
     42                        50                                4.4
     75                        49                                2.4

[JayBay]

EAST BASIN
     Depth (ft.)         Temp (F)        Dissolved O2 (mg/L)
         10                    64                       9.0
         36                    54                       3.8
         62                    48                       1.0
WEST BASIN
     Depth (ft.)         Temp (F)        Dissolved O2 (mg/L)
         10                     62                      8.4
         52                     53                      2.1
         98                     50                      3.1
        141                    50                      3.0
*Data for Oct. 8, 2019

[Pointer]

Jay, what type of Oxygen meter are you using? I have one but would like to get a higher grade unit if possible.

Thanks

[JayBay]

Actually I work for the Bureau of Water Supply and this data is taken from a lab report (it's in meters, degrees C, etc.) so I have to convert.  Not sure what their O2 meter is like but I'm sure it is accurate.  Browns like at least 7 mg/L

[Pointer]

Thanks for the info. I have the Environmental Concepts Temp plus Oxygen, not sure how accurate it is. I’m sure whatever meter the BWS is using would be accurate. If anyone knows of a highly accurate O2 meter that’s available please post here or PM me.

Thanks in advance

[JayBay]

AS OF OCT. 6, 2019

WEST BASIN
   Depth (ft.)        Temp. F      D.O. mg/L
           10                              54                             9.3
           59                              53                             8.8
           108                            50                             8.1
           157                            49                             9.5

EAST BASIN
      Depth (ft.)       Temp F        D.O. mg/L
            10                              54                             8.8
            32                              54                             8.3
            59                              50                             0.7