Hetch Hetchy Water and Power reported on April 16 as follows:
Two significant operations will continue to impact flows on the Tuolumne River this month – continued valve releases to maintain Reservoir elevations, and unusual power generation from HPH and KPH as detailed last week.
Valve Releases
We are beginning our UTREP managed releases next week. Our plan is to have a moderately sized peak in O’Shaughnessy Releases starting Monday, April 22, according to the schedule below. Flows will be increased to 3000 cfs Sunday evening
through Monday, and will be held at 3000 cfs until Thursday. Starting Thursday April 25, we will ramp back down to 300 cfs. After some field work, we will return to 1000 cfs. We expect to keep at 1000 cfs or more on the valves at O’Shaughnessy through runoff
(late June, July). The second pulse (6500 cfs or more) is expected to occur sometime in May – timing is uncertain and will depend on inflow patterns.
At Cherry, we will be operating valves on Monday and Tuesday (April 22-23) as part of inspections by the California Division of Safety of Dams. Monday and Tuesday we expect to have 1000 cfs on the valves.
Eleanor is expected to fill, and may spill sometime next week. I do not include Eleanor spill, as it is currently not forecasted. Expect another 500-1000 cfs spill if Eleanor fills this week or next.
This table shows the scheduled flows – these are estimates, and dependent on operational needs. I will send an updated email if timing / magnitude changes significantly. Note that this table has the peak HPH and KPH draft – actual generation
will cycle per the discussion below.
|
Date |
Hetchy Releases |
Cherry Releases |
Eleanor Releases |
HPH Draft |
KPH Spill |
Total |
|
Tuesday, April 16, 2019 |
250 |
10 |
750 |
950 |
300 |
2260 |
|
Wednesday, April 17, 2019 |
250 |
10 |
750 |
950 |
300 |
2260 |
|
Thursday, April 18, 2019 |
250 |
10 |
750 |
950 |
300 |
2260 |
|
Friday, April 19, 2019 |
250 |
10 |
750 |
950 |
300 |
2260 |
|
Saturday, April 20, 2019 |
250 |
10 |
750 |
950 |
300 |
2260 |
|
Sunday, April 21, 2019 |
500 |
200 |
750 |
950 |
300 |
2700 |
|
Monday, April 22, 2019 |
3000 |
1000 |
750 |
950 |
300 |
6000 |
|
Tuesday, April 23, 2019 |
3000 |
1000 |
750 |
950 |
300 |
6000 |
|
Wednesday, April 24, 2019 |
3000 |
500 |
750 |
950 |
300 |
5500 |
|
Thursday, April 25, 2019 |
2250 |
200 |
750 |
950 |
300 |
4450 |
|
Friday, April 26, 2019 |
1688 |
200 |
750 |
950 |
300 |
3888 |
|
Saturday, April 27, 2019 |
1266 |
200 |
750 |
950 |
300 |
3466 |
|
Sunday, April 28, 2019 |
949 |
200 |
750 |
950 |
300 |
3149 |
|
Monday, April 29, 2019 |
712 |
200 |
750 |
950 |
300 |
2912 |
|
Tuesday, April 30, 2019 |
534 |
200 |
750 |
950 |
300 |
2734 |
|
Wednesday, May 01, 2019 |
400 |
200 |
750 |
950 |
300 |
2600 |
|
Thursday, May 02, 2019 |
300 |
200 |
750 |
950 |
300 |
2500 |
|
Friday, May 03, 2019 |
1000 |
200 |
750 |
950 |
300 |
3200 |
|
Saturday, May 04, 2019 |
1000 |
200 |
750 |
950 |
300 |
3200 |
|
Sunday, May 05, 2019 |
1000 |
200 |
750 |
950 |
300 |
3200 |
|
Monday, May 06, 2019 |
1000 |
200 |
750 |
950 |
300 |
3200 |
HPH and KPH Generation
We have a significant change to our power generation this week. Power prices are actually negative during some hours, meaning HHWP is paying to generate. We would prefer not to. So, generation from Holm and Kirkwood Powerhouses will be
reduced significantly from 8AM to 2PM starting Thursday April 10 and running until the power market corrects.
We will have at least 3 days notice of changes to the power generation schedule, and will let you know when changes are going to be scheduled.
Expected generation will look like this (usual caveats – flows are estimates, and can change any time due to operational constraints):
|
Hour Starting |
HPH |
KPH |
|
0:00 |
950 |
300 |
|
1:00 |
950 |
300 |
|
2:00 |
950 |
300 |
|
3:00 |
950 |
300 |
|
4:00 |
950 |
300 |
|
5:00 |
950 |
300 |
|
6:00 |
950 |
300 |
|
7:00 |
950 |
300 |
|
8:00 |
30 |
0 |
|
9:00 |
30 |
0 |
|
10:00 |
30 |
0 |
|
11:00 |
30 |
0 |
|
12:00 |
30 |
0 |
|
13:00 |
30 |
0 |
|
14:00 |
950 |
300 |
|
15:00 |
950 |
300 |
|
16:00 |
950 |
300 |
|
17:00 |
950 |
300 |
|
18:00 |
950 |
300 |
|
19:00 |
950 |
300 |
|
20:00 |
950 |
300 |
|
21:00 |
950 |
300 |
|
22:00 |
950 |
300 |
|
23:00 |
950 |
300 |
Any significant changes to the schedule will be posted on the bulletin board.