0
$\begingroup$

Why was Trinity Lake's control regulating discharge increased from 0 to 1,477 CFS on March 6 .. 20, 2023? (During historic drought in California.) What is "control regulating discharge"?

enter image description here

It seems difficult to justify discharge from either a consumption or flood control standpoint. Currently water consumption is low because of constant rains across the state, combined with strict irrigation limits due to continuing drought. While most large California reservoirs are at seasonal average capacity as of March 20, 2023, Trinity Lake is at only 50% of its average for this time of year. Most consumers have access to lower-altitude sources like Oroville (which is currently overflowing) and Shasta (which is just 70 miles downstream of Trinity and currently at seasonal average capacity). In this situation, wouldn't we expect water managers to retain water in high-altitude lakes, particularly the ones that are taking longer to fill up?

$\endgroup$

3 Answers 3

3
$\begingroup$

"Reclamation began the project last fall to rehabilitate the reservoir’s hemispherical bulkhead during low lake levels. Reinstallation of the bulkhead began on March 6 and requires a temporary bypass of the Trinity Powerplant for approximately three weeks. During this time the public may notice water releases from the dam’s auxiliary valve. These are normal water releases into the Trinity River that are required for flow augmentation. No additional water is being released as part of the dam maintenance project,"

Bureau of Reclamation Area Manager Donald Bader told KRCR on Wednesday March 22nd 2023.

$\endgroup$
1
  • $\begingroup$ I think you're on to something here. Can Donald's statement be elaborated? By "flow augmentation", is he referring to the EPA regulation? So he's saying that the EPA requires the state to dump 1 billion gallons of (specifically) Trinity Lake water into the ocean every day to maintain water quality? (Or is this just how the state chooses to meet EPA standards?) $\endgroup$ Mar 23, 2023 at 20:00
1
$\begingroup$

As Walt's answer points out, water is being dumped for "flow augmentation". I.e., environmental purposes. The specific program is the Trinity River Restoration Program which aims “to restore and maintain the Trinity River’s anadromous fishery resources … [by] … rehabilitating the river itself”

TRRP is currently under investigation for massive water waste during historic drought.

$\endgroup$
0
$\begingroup$

The decision to release some water may have had more to do with managing the demand of the downstream reservoirs and user network than controlling and regulating the water at the lake.

Water managers should consider a variety of factors, such as supply, user demand, and weather patterns.

In high-altitudinal lakes, it makes sense to keep a water reserve, but water managers must strike a balance between this and the complex needs of users further downstream.

$\endgroup$
1
  • $\begingroup$ You're suggesting that some downstream lake needs more water than Trinity (which is at 50% of seasonal average). However, all the major lakes I see listed on the CDEC webpage are at 96% or higher of seasonal average. So far as I can tell, Trinity IS the drought. Which lake is currently in greater need? $\endgroup$ Mar 22, 2023 at 16:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.