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000
FGUS65 KSTR 071709
ESPNM
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COLORADO BASIN RIVER FORECAST CENTER
NATIONAL WEATHER SERVICE
SALT LAKE CITY UT
May 7 2021

        WATER SUPPLY INFORMATION FOR
            SAN JUAN RIVER BASIN


PRECIPITATION (% OF AVERAGE) AND SNOWPACK (% OF MEDIAN):

SUBBASIN                 APR PRECIP     OCT-APR PREC    MAY 1 SNOWPACK
----------------------   ----------     ------------    ---------------
ABOVE NAVAJO RES              30            75               65
ANIMAS                        35            65               60

******************************************************************************
OBSERVED STREAMFLOW SUMMARY (% OF AVERAGE):

                         APR FLOW       OCT-APR FLOW
----------------------   --------       ------------
BASIN AVERAGE                40             35

******************************************************************************
RESERVOIR STORAGE (KAF) AS OF APRIL  30, 2021:
Figures are in 1000 Acre Feet
                           C U R R E N T   Y R              L A S T   Y R
                           Usable     EOM Usable % of       EOM Usable   % of
                           Capacity   Contents   Capacity   Contents     Capacity
----------------------------------------------------------------------------------
   LOS PINOS - VALLECITO|      125.4|        56.6|     45|       95.1|        76|
---------------------------------------------------------------------------------
   SAN JUAN - NAVAJO RES|     1696.0|      1044.6|     62|     1296.8|        76|
--------------------------------------------------------------------------------
   FLORIDA - LEMON RESER|       39.8|        13.2|     33|       19.8|        50|
---------------------------------------------------------------------------------
  T O T A L S           |     1861.2|      1114.4|     60|     1411.7|        76|
**********************************************************************************

STREAMFLOW FORECASTS
San Juan River watershed
                           Period     50%  %AVG    10%    30%    70%    90%    AVG
                           ------    ----  ----   ----   ----   ----   ----    ---
San Juan River
  Pagosa Springs           Apr-Jul    122    57    150    133    114    103    215
  Pagosa Springs           May-Jul     94    52    122    105     86     75    180
  Carracas, nr             Apr-Jul    205    54    255    220    190    173    380
  Carracas, nr             May-Jul    160    53    210    175    145    128    300
Rio Blanco River
  Pagosa Springs, nr, Bla  Apr-Jul     34    63     43     38     32     29     54
  Pagosa Springs, nr, Bla  May-Jul     26    58     35     30     24     21     45
Little Navajo River
  Oso Div Dam,bl,chromo,n  Apr-Jul    3.9    51    5.1    4.3    3.5    3.1    7.6
  Oso Div Dam,bl,chromo,n  May-Jul    2.8    52    4.0    3.2    2.4    2.0    5.4
Navajo River
  Chromo, nr, Oso Div Dam  Apr-Jul     39    60     49     43     37     34     65
  Chromo, nr, Oso Div Dam  May-Jul     31    57     41     35     29     26     54
Piedra River
  Arboles, nr              Apr-Jul     90    43    119    100     81     68    210
  Arboles, nr              May-Jul     68    44     97     78     59     46    153
Los Pinos River
  Vallecito Reservoir, Ba  Apr-Jul     92    47    119    102     80     71    194
  Vallecito Reservoir, Ba  May-Jul     78    46    105     88     66     57    171
San Juan River
  Navajo Reservoir, Archu  Apr-Jul    325    44    410    345    295    265    735
  Navajo Reservoir, Archu  May-Jul    245    43    330    265    215    186    565
Florida River
  Lemon Reservoir, Durang  Apr-Jul   19.5    35     28     23   17.0   14.5     55
  Lemon Reservoir, Durang  May-Jul   17.0    35     25     20   14.5   12.0     49
Animas River
  Durango                  Apr-Jul    164    40    250    193    145    118    415
  Durango                  May-Jul    146    40    230    175    127    100    365
San Juan River
  Farmington               Apr-Jul    405    37    610    460    365    330   1100
  Farmington               May-Jul    325    37    530    380    285    250    880
La Plata River
  Hesperus                 Apr-Jul    7.0    30   10.5    8.2    6.1    5.0     23
  Hesperus                 May-Jul    5.5    30    9.0    6.7    4.6    3.5   18.2
San Juan River
  Bluff, nr                 Apr-Jul    375    34    590    440    335    300   1100
  Bluff, nr                 May-Jul    295    35    510    360    255    220    855
Mancos River
  Mancos, nr               Apr-Jul    7.5    24   10.5    8.5    6.3    5.5     31
  Mancos, nr               May-Jul    6.0    25    9.0    7.0    4.8    4.0     24

50% Most probable volume in 1000 acre-feet.
%AVG  Most probable volume in percent of the 1981-2010 average.
10% Volume that has a 10 percent chance of being exceeded.
30% Volume that has a 30 percent chance of being exceeded.
90% Volume that has a 90 percent chance of being exceeded.
70% Volume that has a 70 percent chance of being exceeded.
AVG   average volume for the 1981-2010 period.

All forecast volumes reflect natural flow.  Actual observed flow may
be affected by upstream water management.

CBRFC/NIELSON