When the Levee Breaks

A forum that'll feed your need for exploring the limitless adventure possibilities found in "other" places. Post trip reports or ask questions about outdoor adventures beyond the Sierra Nevada here.
Post Reply
User avatar
Tom_H
Topix Expert
Posts: 795
Joined: Tue Jul 10, 2012 1:11 pm
Experience: Level 4 Explorer
Location: Camas, WA

Re: When the Levee Breaks

Post by Tom_H »

Lumbergh21 wrote:And what does aquifer water levels have to do with surface water usage? If your a water system that is supplied by Shasta, Oroville, and any one of the smaller reservoirs in the state, the governor is still requiring you to enforce conservation with fines if you fail to make your customers conserve.
Let me start by saying that I do not approve or disapprove of the way things are. Water rights are complicated. In some cases, local people might control the water rights to where they live. Sometimes those rights are sold to others. Sometimes water rights are held by state or federal governments. My guess is that AG interests hold enough rights to reservoirs in those places you listed (just as Russ mentioned) and that that surface water will go to Central Valley (particularly San Joachin Valley and Tulare Lake Basin) farmers. At the same time, they will refrain from using well water so that the groundwater aquifers can recover a little bit (or at least not be drawn further down). They will likely leave no land fallow this year and will try to make up for not being able to plant as much during the previous five years. Of course, greater produce supply will drive down prices.

There was a time when LA and Imperial Valley farmers drew almost every last drop of water out of the CO River, but Mexico successfully won a case that they held rights to a certain amount of the water based on historical flows through their land. There is the potential for a lot of AG in the Imperial Valley. As Las Vegas and other places that draw from the CO have grown, there is less left for downstream usage. When the state says that not all of CA is out of drought, that includes the Imperial Valley. I haven't read how the snowpack is doing on the western slopes of the Rockies, but a lot of that flow needs to go toward refilling Lakes Mead and Powell and how much is left for Vegas, Imperial Valley AG, LA, and Mexico is likely still below historical averages. Imperial Valley farmers may plant more than the last several years if they can get more water, but they most likely will be nowhere near the acreage they once were able to plant.

I don't know a whole lot about water rights law, but I do know that the people who live in a place don't necessarily "own" the precipitation that falls there. Remember that LA lawyers tricked Owens Valley residents to sign away the rights to most of their water. Residents were not able to change that even a century later, but environmentalists were able to get courts to restore a bit of that water to the basin in an effort to stabilize Mono Lake. Water rights go far beyond local control and there are a lot of powerful players involved. Please don't shoot me for saying all this :tear: :snipe: cause I didn't make the rules. All I'm saying is that from a legal standpoint, water rights is a very complicated thing, something way beyond my station in life.
Last edited by Tom_H on Sat Feb 11, 2017 10:39 pm, edited 2 times in total.
User avatar
rlown
Topix Docent
Posts: 8225
Joined: Thu Oct 25, 2007 5:00 pm
Experience: Level 4 Explorer
Location: Wilton, CA

Re: When the Levee Breaks

Post by rlown »

Tom, how are things with Consumnes and Elk grove? curious.

Let me guess: http://www.abc10.com/news/local/evacuat ... /406969846
User avatar
Tom_H
Topix Expert
Posts: 795
Joined: Tue Jul 10, 2012 1:11 pm
Experience: Level 4 Explorer
Location: Camas, WA

Re: When the Levee Breaks

Post by Tom_H »

rlown wrote:Tom, how are things with Consumnes and Elk grove? curious.

Let me guess: http://www.abc10.com/news/local/evacuat ... /406969846
Remember, I sold my house and am in a West Laguna apartment while we wait for a new house to get built in WA. I heard that Deer Creek rose above the roadway on the bridge. I don't know whether the levee broke again at the vineyard, but I would think it probably did. The Union Pacific railbed near the place that CA 99 crosses the Cosumnes got so waterlogged that one side just sank down when a freight train went over it and most of the train rolled over into the water. There were train axles laying loose all over the place and the water was turning red from a few ruptured cans of tomatoes. There were only canned tomatoes and one other raw AG product on the train, so nothing toxic in the water.

https://www.youtube.com/watch?v=MoQJyKbGISk

https://www.youtube.com/watch?v=2vknl4YNXww
User avatar
Wandering Daisy
Topix Docent
Posts: 6694
Joined: Sun Jan 24, 2010 8:19 pm
Experience: N/A
Location: Fair Oaks CA (Sacramento area)
Contact:

Re: When the Levee Breaks

Post by Wandering Daisy »

Aquifer levels have a LOT to do with surface water usage. It is economic. Those AG wells in the central valley are up to 1000 feet deep. Many are pumping the lower confined aquifer, not the upper aquifer. It takes a lot of electricity to pump water. When there is sufficient surface water available, it is usually cheaper, at least for those with older water rights. As for recharge, the lower aquifer does not get recharged by percolation from the surface directly above. There is a 50-100 foot clay layer (called the E-clay) that stops that recharge, at least in the southern part of the Central Valley. Lower aquifer recharge is from dipping sandy zones that reach the surface on the east edge of the Central Valley. It then takes a lot of time for the recharge to work its way westward to the farm areas where it is pumped. Droughts have lingering effects. The question is not necessarily water policy for droughts - it is water policy to handle more extreme swings in conditions; longer more severe droughts, followed by more severe wet period flooding. And our main "reservoir", the Sierra snowpack, is tending to melt earlier, requiring more storage space, if is to be utilized. Tom is absolutely right, water rights are complicated, highly political, and any changes take decades of litigation.

I looked at several you-tube videos last night of Oroville Dam. For all the criticism of the standard news outlets being sensational, nothing is more sensational and based on fallacies as some of the "real news" sites. Talk about fear mongering! Caution is good. But telling people that the dam is about to break, is just sensational. Could it? Yes, but not likely. There is no 100% certainty in the water business.

As for the 100-year flood, etc. Those are just statistical tools to use when designing water systems. You always have to balance cost with safety. You cannot have 100% safety; there just is not enough money for that. For example, low cost stuff, like residential street gutters, are often designed for the 2-year flood. An expensive structure like Oroville Dam is designed and operated for bigger events. Just because you have a 100-year flood one year does not mean that you have less of a chance for a 100-year flood the next year. These statistical tools are also revised periodically. I think after the 1997 floods they recalculated them.

:soapbox: Ok, I had to get on this soapbox. It irks me no end with laymen think they know better than the entire DWR, which is one state agency that is full of very well qualified professionals, running a very complex water system. I think they do a really great job. Very dedicated; very capable.
User avatar
Wandering Daisy
Topix Docent
Posts: 6694
Joined: Sun Jan 24, 2010 8:19 pm
Experience: N/A
Location: Fair Oaks CA (Sacramento area)
Contact:

Re: When the Levee Breaks

Post by Wandering Daisy »

Oh, guess I did not explain one thing very well. If you have a well and are pumping water from the lower aquifer, the level of the water you pump is not the depth of the well - it is water level in that well. It does not go up and down due to drops of water recharged at the well location. It goes up and down due to the pressure head, that is recharged at the edge of the Sierra. You do not actually wait for any drop of water to migrate eastward. Over pumping reduces the pressure head.

I was really surprised when I first started working on groundwater here. There are thousands!! of very large agricultural wells with an awesome cumulative effect on the aquifers. Surface water deliveries to farmers are good for everyone in that if it allows farmers to pump less, we all win because we all depend on the aquifer some way or another.
User avatar
rlown
Topix Docent
Posts: 8225
Joined: Thu Oct 25, 2007 5:00 pm
Experience: Level 4 Explorer
Location: Wilton, CA

Re: When the Levee Breaks

Post by rlown »

I don't think we all win. I'd like to keep the "normal" salinity levels in the delta, meaning a balance between letting the Northern area flush the bay as it's supposed to rather than shipping water to the South w/o restriction (are some). I know, Ag is important, but not during "dry" conditions (my opinion.) Cotton and almond crops come to mind for some reason.

Wasn't sure if this qualifies as "fake" news: https://water.usgs.gov/edu/earthgwlandsubside.html

I do agree that surface water is cheaper to use, but we don't seem to store as much as we might need to in a 5 year drought. You know there'll be another "drought" in the future..
User avatar
Jimr
Forums Moderator
Forums Moderator
Posts: 2178
Joined: Fri Jul 31, 2009 2:14 pm
Experience: Level 4 Explorer
Location: Torrance

Re: When the Levee Breaks

Post by Jimr »

Is the Central Valley aquifer system subject to intrusion of sea water like coastal aquifer systems are?
If you don't know where you're going, then any path will get you there.
User avatar
Wandering Daisy
Topix Docent
Posts: 6694
Joined: Sun Jan 24, 2010 8:19 pm
Experience: N/A
Location: Fair Oaks CA (Sacramento area)
Contact:

Re: When the Levee Breaks

Post by Wandering Daisy »

I was referring to the you-tube "news" where they were saying two days ago that the dam was ready to break any moment. Subsidence is a well studied and verified problem that has been going on a long time. The California water project was partially built to address that - provide surface water so less groundwater had to be pumped. Subsidence was caused by extreme over pumping of groundwater. Until groundwater pumping is regulated (this is mainly a political issue), supplying surface water to agricultural interests keeps them from over pumping for economic reasons. The problem with Almonds, is that the trees need continual water- you cannot fallow a field of almond trees during drought. Cotton may be a water waster but you can fallow fields during droughts.

Jim - Salt water does get drawn into the Central Valley aquifer. But not directly from the ocean. Groundwater in the Coast Range is salty because it is a geologically recent mountain range made of sea sediments. The salt is "old" water. The fresh recharge from the Sierra and the salty recharge from the Coast Range meet west of the center of the valley - almost along I-5. The pressure head on the Sierra water is greater and keeps the salt water back. Too much pumping between the saline boundary and the fresh water recharge can reduce that pressure and cause the salt water to migrate eastward. This is particle migration so it takes time. Actual molecules of water or salt move very slow although the pressure changes that drive it is an immediate reaction. That is a bit of a simplification. I have also been retired from this field for several years now and am not up on the latest science for all this. On the west side, salt issues in the upper aquifer are irrigation drainage problems. West side soils are just more salty than east side soils and these salts get dissolved.

All this points to the Sierra snowpack as so important to not only surface water supply but keeping aquifers healthy. The big long-term issue is how to store Sierra snowmelt if it continues to melt earlier and too quickly due to warming climate. And this is also a political problem.

I think most of us who are or were in the past into the science of water get frustrated that it all boils down to politics. Unfortunately our current political environment is pretty dysfunctional.
User avatar
sparky
Topix Fanatic
Posts: 1030
Joined: Tue Jul 20, 2010 10:01 am
Experience: Level 4 Explorer

Evacuation - Oroville Dam

Post by sparky »

Evacuations Ordered Due to ‘Hazardous Situation’ Developing at Oroville Dam Emergency Spillway

http://fox40.com/2017/02/12/evacuations ... -spillway/
User avatar
sparky
Topix Fanatic
Posts: 1030
Joined: Tue Jul 20, 2010 10:01 am
Experience: Level 4 Explorer

Re: Evacuation - Oroville Dam

Post by sparky »

The expect failure within 1 hour. Evacuate now if you live below the dam!!
Post Reply

Who is online

Users browsing this forum: No registered users and 7 guests