SWSIReportJune2004

• Title: Colorado Water Supply Conditions Report
• Date: 6/15/2004
• Description: Presentation
• Basin: Statewide
• Drought Mitigation - Doc Type: Presentation

SOUTH PLA TIE BASIN

Basinwide CondItIons Assessment
The SWSI value of -Q2 Indicates that for May the
basin water supplies were about normal Reservoir storage,
the major component in this basin in computing the SWSI
value, was 100% of norma! as of the end of May,
Cumulative storage in the major plains reservoirs: Julesberg,
North Sterling, and Prewln. is at 64% of capacity.
Cumulative storage in the major upper.basln reservOlrs_
Cheesman. Eleven Mile. Spinney, and Antero is at lOOk of
capacIty. Flow at the gaging station South Platte River near
Kersey was 399 cfs. as compared 10 the long-term average
of 2.401 cfs Flow at the Colorado/Nebraska state line
averaged 34 cfs
Stream flow continued to be very low as represented
by the Kersey gage, a key measure of flow in Ihe South
Platte basin, through oul most of May due to the continued
dry conditIons and the lack of snowmelt runoff. While not
near as low as the flow in May 2002 when average flow
averaged approximately 200 cts, the average May 2004 flow
of approximately 400 cfs is sigmflcantly below the average
flow of 2400 cfs
Because of the low flow conditions, direct flow calls
continued through oul the month of May. In contrast, the
direct flow call last year and many years does not occur at all
in May. Because of the direct flow call, there was no
reservoir storage on the mainstem or tributaries and many
reservoirs remain significantly below capacity.

Outlook
We do not expect much If any runoff to make It to the
mainstem of the South Platte due to the low snowpack. In
years WIth low snowpack, most or aU the water ends up being
used on the various tributaries to the South Platte as the
senior rights are on the tributaries,
Withoul high flows created by runoff, we do not
expect there to be any additional storage WIthin the basin.
The unfilled storage could pose a significant water supply
concern later this summer, especially for agricultural users If
It remains dry,
Because of this, Oivision 1 has required that all
upstream out-of-priority storage be released WIthin the basin
to satisfy senior users In most years, there IS no
requirement to release out-of-prionty storage on most of the
tributaries as senior reservoirs fill.

Administrative/ManaQement Concerns
Many cities have implemented their drought control
plans to reduce demand because of the dry conditions.
However, we do not anticipate malor shortfalls for most
muniCIpal suppliers like 2002 unless there is a conSiderable
period of drought as thIS is a better year than 2002 thus far
and most suppliers have had lime 10 make addItional
preparations for dry conditions since 2002.

Jun-04

_.-

.

.1

t'i
,
,
n

i

.1

____..........:r-.........."...,,,.....
-~

SOJTl-I'"""TTEFlI'IiER'i'l~FlCW9V....-.TUlv&.R

1<<Xl.1XXl

'2((llXXlt.-

-+
+ I
i
~/~
~-- .~~.
-.---:.--- '-'
2IXl1XXl ----=::::~...-= 1=;- l= ~
..-e:'t=-::-.,=---olo=:::: -
o,'--~!'==-; ----,.L
O:J _ c.c .. FcI ~ ..".,.

I
] l.lXXlIXXl.

.~

-+-

~ !Dl1XXl'
~
~
,
,
u

~~.

<<XlOOJt-

. -.

..

__'o\ETI''offlI

.-1R>'(IIl;O,

.,'"

."",

,*1'OlfSIi"''''T1II(,*Sf~

:00....

~_.

_~I~..~.

1

J
.
~ "IHII.,;---

4

.
!~-
. .
,
,

.....t

,.

l::Iobo -f_....~.-..-_l-aoo

.~'9 50~' c.w-

.S/S'lQOc.o.-

J