State of the River (CO streamflow/weather predictions)
I attended the 2004 Colorado State of the River presentation yesterday. The presenters were big wigs from national, state, regional, Denver, and counties surrounding Summit. The attendees were largely local ranchers and real estate types intersted in water rights as well as rafting companies from around the state and ski resort personell involved with snowmaking. I attended as part of Water Rescue. Most of the presentations were rather boring and irrelevant to my interests.
I thought CO kayakers would be intersted in this information.
So here is most of what I submitted to the team.
2004 Colorado State of the River, May 11, 2004
I have done my best summarize the two hour meeting concentrating on information relevant to dive and swiftwater operations.
NOAA (National Oceanographic and Atmospheric Administration):
Brad Udall gave a quick presentation on the drought conditions and long-range forecasts. We can expect higher than normal temps through the fall and it will be dry until mid-July or even later when our monsoon season starts. El Niño is unlikely for the next few months. Forecasts indicate equal chances of normal vs dry vs wet weather over the summer for our area.
The river flow predictions were dismal for pretty much all the rivers especially the Colorado and the Yampa. The Colorado River basin has seen 50-70% normal precip and the Arkansas has seen around 70%. Most of the state is under D1 Moderate with some under D2 Severe drought conditions with a small spot near Wolf Creek that is D0 Abnormally Dry and only a small portion under D3 Extreme. Our area is under Moderate drought and these conditions are predicted to persist at least through the fall.
An interesting and depressing report on paleoclimatology for our region indicates that we have been spoiled by unusually wet weather over the last century and that drought years such as 2002 should be expected as often as 12 times a century rather than 4 as well as “dry decades” and overall drier weather in general if the past 600 years is any indication.
CO River Outflow the peak outflow on the Colorado River near Cameo will likely be 4000cfs this year (90% likelihood). River outflows have started unusually early this season and we are now relying on high altitude snowpack as lower snowpacks have almost completely melted in many cases.
Denver Water:
“Normal is not something we can really define anymore.” –Denver Water
A Denver Water commissioner faced the eye daggers of the crowd and touted the “harsh” water restrictions they enforced last year and that they intended to use the same restrictions this year, despite the lower precipitation levels, to limit water use in their district. It is suffice to say that the restrictions enacted by DW pale in comparison to the restrictions that might be seen in other areas, Texas for example, given the D1 and D2 drought (moderate and severe) levels affecting their water supply basins.
DW reported that they ceased cloud seeding operations during the 3rd week of March due to lack of funds combined with “acceptable” levels of precip. Cloud seeding operations are to resume at some point this year “unless Kansas files a cloud rustling lawsuit.”
Dillon Reservoir:
*ommitted long irrelevant section on Dillon Reservoir level predictions*
Outflow levels for Dillon are currently at 50cfs and will likely remain so through June. From July through September predicted outflow rates are 100-300cfs.
Lake Granby:
DW intends minimum required streamflow releases. All other inflow will be stored and inflow is predicted to be only 64% of average. Granby is predicted to e 40ft down.
Outflow levels below Granby will be 53cfs during May, June, and July, 28cfs in August, 14cfs in September, and 20cfs thereafter.
Green Mountain Reservoir:
Planned operations for Green Mountain are to store as much as possible during May and June with minimal releases. July through October, all inflow will bypass as replacement releases. These later releases will be agricultural and environmental (Sr. rights) but DW and CSU could reduce physical releases. The reservoir will likely be down 50ft.
Outflow before June will be 80cfs. During July, the outflow will be 700cfs.
Continental-Hoosier Project (Colorado Springs Utilities):
CSU states that they only intend to divert 84% of the usual amounts into the tunnels, Upper Blue and Montgomery Reservoirs. They report snowfall at 150in or 82% avg. (184” normal) with April 1 snow water equiv of 9 and May 1 snow water equiv of 12. The Upper Blue reservoir is at 135AF or 6% full, diverting 8cfs. Montgomery Reservoir is at 930Af or 34% capacity diverting 23cfs from the Hoosier Tunnel. CSU predicts diversions to the Upper Blue to average 50cfs during June and flow through the Hoosier Tunnel to average 80cf. July predictions are to continue diversions on 1929 and 1948 rights if river call allows.
100 Year Refill:
A hydro plant near Glenwood is undergoing a major overhaul and has been shut down since March. Reservoirs upstream of the power plant have been able to shore up their levels out of priority during the maintenance. One turbine will come online later this month and the second turbine will be back online by late June. I would assume that river flow would need to meet the senior rights of this plant once it goes back online.
Wolford Reservoir:
Wolford Reservoir near Kremmling will make releases to meet water calls in lieu of releasing from Green Mountain Reservoir.
Conclusions:
*ommitted*
[bender]We're boned.[/bender] They seemed to say it would be a year between 2002 and 2003.
