The Facts About The Pit River Hydropower Relicensing
Despite a Contentious Relicensing Process, CalTrout Works To Protect and Restore One Of California’s Blue Ribbon Rivers
While the Pit River is one of California’s best-known destinations for fly fishermen, it’s also one of the state’s most controlled, hydrologically modified rivers.
California's Pit River (photo courtesy Val Atkinson)
Despite still providing an excellent fly fishing experience, the notoriously hard-to-wade Pit River’s most popular reaches — Pit 3, 4 and 5 — have been impacted by a low, highly controlled flow regime. So when the Pit River hydropower complex came up for relicensing, CalTrout negotiated to protect and restore the health of the fishery — and for the benefit of California’s anglers.
Through the course of extensive studies, what we discovered was not exactly what we expected…
The Pit River Was Not Entirely Healthy
Extensive studies revealed some surprising facts about the Pit River, including some which were having a significant impact on fishermen. For example:
- The Pit 4 reach supports approximately half the trout biomass as Pit 3
- Pit 5 only supports approximately half the trout biomass as Pit 4
Given the Pit’s status as a Blue Ribbon fishery, this was alarming information; the river was not as healthy as we believed.
After crunching the data from over $10 million in studies, CalTrout identified four problem areas which needed attention during the negotiations:
- High Summer Water Temperatures
- Sub-Optimal Flows for Habitat
- Lack of Purging Flows
- User Conflicts
Solutions
Facing the steady decline of one of California’s iconic rivers, CalTrout (along with Trout Unlimited [TU] and Federation of Fly Fishers [FFF]) invested a lot of time and effort in the lengthy hydropower relicensing process, and though we didn’t emerge with exactly the outcome we wanted, we are confident we’ll see an improvement in the health of the fishery under the new flow regimes.
Problem: Water Temperatures
The Pit River (especially Pit 4 and 5) suffered from high water temperatures during the summer months (especially July and August) — often exceeding 70 degrees, which is too hot for healthy trout.
We negotiated a new flow regime in Pit 4 and 5 that will reduce daily maximum and mean stream temperature by 2-2.5 °F, bringing water temperatures in Pit 4 & 5 reaches into the optimum growth range for trout during the summer months (approximately 66 degrees).
That means flows will generally increase from the current 150 cfs to 350 cfs – 400 cfs on Pit 4 and Pit 5. In simple terms, new flow regimes for Pit 4 and 5 should grow larger, healthier trout in these two reaches.
Problem: Flows Too Low for Optimal Habitat
“Wettable area” studies suggested optimal habitat flows for Pit 3, 4 & 5 were far higher than the current base flows (often, the best flows for fish were in the 600 cfs range).
At current flows, optimum trout habitat was often located in the thalwag (the area of highest flow in the channel) — near the center of the river.
Flow modeling indicated that as Pit River flows were increased, optimum trout habitat moved from the thalwag to better habitat at the edges of the river — where they’re more accessible to anglers.
Like the temperature issue covered above, higher flows were needed to improve and restore the fishery. This is why — despite CalTrout’s attempt to peg Pit 3 flows at 200 cfs — other participants successfully negotiated flows at 300 cfs and above. (See flow data at end of article.)
Problem: Lack of Freshet Flows
The lack of periodic freshet (purging) flows meant the river channel was narrowing and bug/trout habitat in the river was not being renewed.
CalTrout negotiated freshet flows a minimum of every other year (if they don’t naturally occur), which should improve habitat for invertebrates, trout and spawning. (See flow data at end of article.)
User Conflicts
Whitewater interests wanted high pulse flows most weekends during the summer months, an option we found untenable.
Instead, after a delay until 2013 to gather baseline data, “whitewater flows” will occur occur only one weekend in August (maximum of 1500 cfs) and one weekend in September (maximum of 1200 cfs) — and the impacts of those flows on invertebrates and trout will be closely monitored.
Should significant impacts appear, the adaptive management process we helped negotiate allows us to return to the negotiating table and potentially stop reduce or eliminate whitewater flows.
The Fishability of the New Flow Regime
Fishermen have voiced concern (sometimes vigorously) about the fishability of Pit 3, 4 & 5 under the new flow regime.
Because no party to a negotiation gets exactly what they want — other stakeholders looked at the studies and advocated for flows far higher flows than CalTrout wanted — the final flow regimes are excellent for the fishery, but a bit higher than many consider optimal for fishermen.
CalTrout initially wanted to raise flow rates in Pit 3 from 150 cfs to 200 cfs, and raise flow rates in the troubled Pit 4 and Pit 5 sections to 350 cfs.
In addition, we took a very cautious stance on the request for ongoing “pulse” flows for whitewater recreational use, concerned about impacts on invertebrate populations.
The negotiated Pit 4 and Pit 5 flows were only a little higher than we wanted, but Pit 3 — which didn’t suffer from summer water temperature issues — ran far higher than we wanted.
Fishermen typically end up begging for more water in streams and rivers, and there’s little doubt — despite a few statements to the contrary — the new flow regime will have a positive (potentially hugely positive) impact on the health of the Pit 3, 4 and 5 fisheries.
The problem for fishermen becomes one of access; how do you fish a Pit 3 at 300 cfs when you’re used to fishing it at 150 cfs?
We believe several things may help mitigate the higher flows for fishermen:
- At higher flows, trout will move from center channels to better habitat on the edges, making them more accessible to fishermen who can’t wade into the main channel
- Higher flows will tend to widen the channel and remove encroaching riparian vegetation, resulting in a “flatter” river channel and better access than is currently experienced at these flows
- Freshet flows will restore bug and spawning habitat, improving trout populations
- Optimal water temperatures will grow more — and bigger — trout
Summary
In the new Pit River license we achieved the following:
- Substantially increased minimum flows that optimize trout habitat and lower maximum water temperatures
- A guarantee of appropriate spring freshet flows designed to mimic historical flows that are important for cleansing spawning gravels and maintaining fish habitat
- A complete re-operation of Lake Britton to more closely mimic run-of-the-river flow fluctuations resulting in a more natural flow patterns during the winter and spring months
- A limit on ramping rates for power fluctuations which have occurred due to the critical role this project plays in power generation
- A very substantial investment in monitoring studies during the life of the license to monitor response of fish, habitat and other aquatic resources to the new flow regime
- An adaptive management process whereby conditions can be modified based on outcome of the monitoring
- Increased PG&E responsibility for maintenance of the Hat Creek fish barrier and a $300,000 enhancement and restoration fund for the Hat Creek Wild Trout Area.
CalTrout — along with Trout Unlimited and the Federation of Fly Fishermen – are confident conditions of the new Pit license are in the best interest of this remarkable river and fishery.
We look forward to fishing these new flows and we hope you do as well. Providing your feedback is important as CalTrout will be consistently involved in meetings to review data and provide feedback to PG&E and agencies.
This adaptive management process allows for changes in the license based on data being collected. The important thing to know is CalTrout will continue to stay involved in the future of the Pit River.
Flow Data
Pit 3
Summer – 300cfs (4/21-8/31); Fall – 280 cfs (9/1-11/1); Winter – 300cfs (12/1-4/20 [prior to spill]); Winter – 350cfs (11/1-4/20 [after spill])
Pit 4
Summer – 375cfs (5/16-8/31); Fall – 350cfs (9/1-11/1); Winter – 375cfs (12/1-6/15 [prior to spill]); Winter – 450cfs (11/1-6/15) [after spill])
Pit 5
Summer – 400cfs (4/21-8/31); Fall – 350cfs (9/1-11/1); Winter – 400cfs (12/1-4/20) [prior to spill]); Winter – 450cfs (11/1-4/20) [after spill])
Freshet flows Freshet flows of 1500 cfs will be provided every other year, if natural freshet flow does not occur in a Project reach in the late winter and early spring.
A freshet flow release is a 21 day flow release with a two day average flow of 1500cfs, after which the flow decreases in approximately five equal steps.
Recreational Flows
- One weekend in August (minimum flows of 1500 cfs from 10:00 am to 4:00pm)
- One weekend in September (minimum flows of 1200 cfs from 10:00am to 4:00pm in the Pit 5 reach)
These flows will not begin until 2013 at the earliest. Over the next two years baseline data for fish, bugs and others creatures will be collected at the new base flow. This data allows us to review the impacts of recreation flows on the fishery, and the adaptive management process allows us to petition to have them modified.
Pit River Background
The Pit River offers up excellent water chemistry — reflected in its abundant invertebrate life and excellent hatches — but as a river, it has been dramatically altered by 80 years of hydro engineering.
For example, pre-dam flows in the relevant sections rarely fell below 1800 cfs, yet after the series of dams were completed in the early 1920’s, flows in some sections were essentially nonexistent (Pit 3 didn’t receive any real water until a successful CalTrout petition to augment flows in the 80s).
Some water was eventually restored, but even today, low flow rates mean high water temperatures for trout, which favor warmwater species like suckers and pikeminnow to the detriment of native trout populations. (High water temperatures reduce dissolved oxygen, rendering trout far more susceptible to disease and reducing growth rates.)
Chronically low flows also have the effects of smothering bug and spawning habitat while encouraging growth of riparian vegetation and narrowing the channel, artificially “shrinking” the Pit River.
11 Comments
I have been fishing the Pit River for years, trying many areas in Pit 3, 4 & 5. It is hard for me to believe your statement about the ill health of Pit 5. In recent years I have settled on Pit 5 as my favorite section. I regularly encounter more fish there than any other NorCal stream I fish. The population of trout in Pit 5 continually amazes me and it seemed to be just as good or better in 2010 than it was in 2000. I would rank the three stretches in just the opposite order you have, Pit 5 being the best, then Pit 4 and finally Pit 3. It could be that the Pit 3 trout see more fishermen and are therefore harder to catch. Maybe my clumsy approach is not suited to the more well educated trout. All I do know is that the pocker water in Pit 5 was phenomenal, but I tried it once this year with very unsatisfactory results. We’ll see if the new flow regime creates a flatter, more accessable stream channel as predicted in the article. I sure don’t see it yet.
Again, I wonder how the studies were done. Were you looking at trout population in ideal summer habitat (highly oxogenated/white water areas) or the entire stream (including less desirable flat water)?
Finally, I don’t see where this “compromise” between the different user groups has much benefit for either. We have a stream with not enough flow for kayakers except for two weekends per year and too much flow for fishermen.
Regards,
John Bill
John,
Thanks for your informative response. No arguing the Pit is a good place to fish and many of us have our favorite reaches. In Pit 5 our concern was high temperatures in July and August. Flow studies also showed limited habitat area for adult trout. Under the previous flows, there were long sections of flat water–‘frog water’–that did not have the depth, velocity and oxygenation to support adult trout.
The studies were done reach wide in all three reaches using various methods, with the focus being on what flow provides the optimum amount of space for trout (ie what flows provide the highest amount of area that has optimum depth and velocity for adult trout). We coupled this with temperature data at various flows to come up with flow recommendations based on the best possible data.
In regards to the kayakers and fishermen flows, we hear your point. But for us its important to base our flow recommendations on what is best for the fish. That said, we are very attentive to our constituents preferences and what we desire as anglers. We advocated for lower flows, especially in Pit 3, based on angler preference. However, this recreation based argument, around the relicensing negotiating table gets to be a slippery slope with all the varied interests. Each claim they want their recreational interest put as the highest priority whether its fishing, kayaking, swimming, gold panning, or whatever. And we certainly advocate for angling preference, but what carries the day is flows that are best for fish based on the best science available.
Thanks again for your thoughtful response and sharing your experiences on Pit 5. The Pit is wonderfully wild place.
Curtis
I’m confused. I read that “Instead, after a delay until 2013 to gather baseline data, “whitewater flows” will occur occur only one weekend in August (maximum of 1500 cfs) and one weekend in September (maximum of 1200 cfs) — and the impacts of those flows on invertebrates and trout will be closely monitored.”
but later in the article
“pre-dam flows in the relevant sections rarely fell below 1800 cfs”
So the pre-dam condition may not have been optimal for fish either. Seem like we might have missed a win-win situation with our whitewater-loving river partners. And how can we complain about fishability? Or is the statement concerning 1800 cfs meant to represent average winter flows. It seems we are either inconsistent or unclear in our story. And in the future, I’d like to know whether the reaches where sediment-starved and whether pulsed flows would help move and distribute spawning habitat and positively impact the benthic community. Overall I’m pleased with the new flows. Thanks.
Brian;
First, the 1800+cfs flows were common prior to the damming of the Pit River, and the concern over the recreational flows in August in September revolves around the ramp up and down. In essence, “pulse” flows can be hard on fish and invertebrates because of the possibility of stranding in shallow bankside pools as waters recede (and the opposite as they rise).
In other words, it’s not necessarily the flows, but the difference between the two that holds potential for harm (primarily to small fish and invertebrates).
The adaptive management process in place will use sound scientific methods to determine if there are impacts to fish and invertebrates.
As for sediment, winter freshet flows (typically higher, more prolonged and slower-ramping than recreational flows) have been included in the new flow regime. If they don’t occur naturally (they certainly did this year), then artificial freshet flows will be released every other year.
Thanks for the additional insight and quick response!
Brian,
To clarify, 1,800 cfs was average base flow during the summer months before the Pit 3, 4 and 5 dams went in. Which makes sense if you think about the combined inflow of Fall River, Hat Creek, Upper Pit, Burney Creek all converging to go down the Pit canyon. Historically, the Pit canyon in the Pit 3,4,5 reach was likely more of a transition corridor for steelhead and salmon and less of a resident trout fishery. Such are the changes brought by dams—loss of anadromous fish, good trout tailwater fisheries.
And yes, your statement that pre-dam flows were not optimal for fish is partially correct–not optimal for trout. But again maybe better suited for salmon migration. With the dams in place the focus is on trout and flows that optimize depth and velocity specific to them.
Your comment on sediment starved is right on. The dams have cut off gravel inputs to the Pit canyon. The new license calls for modest inputs of spawning gravel at the head of each reach. The amount is meant to coincide with the ability of pulse flows to distribute that gravel. With the macroinvertebrate monitoring taking place we hope to see a positive response in diversity and abundance of the bug community.
Thanks for the feedback and insights.
Curtis
as an old timer of the Pit 1950-60 years and up to 2004, I would say that there was a general decline in the late 90’s – to mid 2000’s of the quality, health and size of the trout taken. The raparian growth was thicker and areas of access to the river on Pit 5 reach, were obstructed by fences and land owners claiming ownership. We have NEVER before, been prevented accesses; in fact we knew most of the locals and often stayed in their accomodations such as at the old Loftin Lodge cabins at the springs. and we would always share a fish or two to those wonderful people. Buck Cantrel was always around for helping us with his jeep to get to hard to reach areas. Much of this is changing but so has the state. We used to have photos of our visits on the wall at the Pit Stop when we would be there with Andy Morgensen, and Jim Buck and if the fish wasn’t at least 2 lbs, it went back to “get more spots”; our methods were natural always and to say of the times that it was “fine”; is the understatement of the century. Thank you Cal Trout for your fine work and we should find there is enough river for everyone…just don’t crowd one another and play nice…”gentlemen are always gentlemen” – (Thanks Dad) – “uffda!”
One other thing…there was Mr. Brownie. He was the overseeing operator of the Dams and plant at pit 5 – Living in a clapboard house up the southern hill from the Dam (sliding gate type) he would always let us in to the ladders to the shive space above the gates in June to pick the salmon flies off the cables. We would keep them in screened cottage cheeze tubs and unless you were all thumbs and were un aware of the year you were born, each one of those salmon flies was a trout looking for a place in your kreel. What times… enough I have told enough. LOL.
Enjoyed your posts Dave Selvey. Thanks Cal Trout for your efforts. Steve
You many not have gotten everything you wanted in the negotiation, but I, for one, am extremely grateful that you’re fighting the good fight. Thank you. Keep it up.
I fished the Pit river 3 and 4 since the eighties. After the water flows were raised above 250cfs. Which are unsafe and impossible to wade at either of these two areas. We have had to move out of state to find fishing as good as the Pit. I am sorry someone made the decision to ruin the best Blue Ribbon River in California. 250cfs is fishable anything above that is not. I have to add this. There were still twenty inch fish in Pit 3. They were fished out of Pit 4. The whole river should have been catch and release.