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deltabighat

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This may be a real dumb question but I always say no question is dumb if you don't know the answer to it. I fish a lot in the old swamp and during the day the current comes roaring out and hours later it changes and comes roaring in. Many times we used to use 8 oz sinkers, if we are bottom fishing, to keep the bait on the bottom. However when I am up in Sacramento or even in Walnut Grove, the current always seems to be heading down river. Generally at what point up river does the tide issue stop and the water is always running down river. I know this is influenced by the degree of tide and the water run off up river but generally where geographically does the tide changes stop.

DBH
 
Depends on how much water is coming down the rivers. I know there's an occasional tidal pull up by Herman and Helens.
 
Depends on the amount of run off. I've fished in the Sac river by Three Mile slough (Brannan Is bridge) in '84 when we had massive rains, and the tide was going "out" for 3-days straight (the amount of time I was anchored there - but no doubt much longer than that).

I don't fish that area that far upstream, but have fished at where the Sac river leaves the ship channel just up from Rio Vista, and if I remember correctly, it comes in above Rio Vista normally - prior to the small mouth of where the real river takes off.

In my readings, I've read where roughly 85% of the fresh water entering the Delta comes down the Sac river.
 
Hal Schell mentioned in one of his books that the Sac River has tidal influence as far upstream as the Feather River.
 
Today. the tide range in Sacramento on the river is 3 feet. As noted above, current is affected greatly by run off. A current prediction station (ie, they know that some amount of directional current will happen almost no matter what) exists on the Sacramento as far up as Point Sacramento, and on the San Joaquin, with far less runoff, all the way east to Vulcan island.

George
 
VHF weather reports for the Delta list tide changes as far as the "I" St Bridge in Sacramento. That is just north of the Tower Bridge and Old Sac. If runoff is enough to keep the current moving downstream, it will just slow down on an incoming tide, but the depth will change. Regardless of current, there will be more "water in the water" on an incoming tide.

I tied up to the west bank of the Sac River and walked over the Tower Bridge to the Jazz Jubilee which is held every Memorial Day Weekend. The currents were not bad, but when I returned to my boat at low tide I had to walk through 20 feet of mud to get to to the back of my boat to board. The tide had gone out 20 ft while I was gone! What a mess.....of course my friends and I were drunk by then, so we just laughed about it and went to sleep. Had a mess of dried mud in the boat to clean up the next day.... Ahhh, the memories!
 
So this may be another stupid question but; Does the incoming tide act as a water damn pushing the outgoing freshwater back upstream or just slowing down the rate of flow causing the rise in water level? If it is only slowing down the freshwater going out to the bay, when the tide receeds does is act like a damn being released and make the current even stronger than it would normally be (vacuum?)?

I guess actually I have three stupid questions? The last one being, is it easier on the engines and fuel mileage travel up/down stream with the tide?
 
Not stupid questions at all! The answer is a little tricky in places like the Delta. In the spring when lots of water is rushing downstream from the mountains in the form of rain and/or melted snow, the fresh water pushes against the incoming tide. Usually the current going out is stronger then the tide coming in, so the water rises and less salt water comes upstream.

During times when very little water is coming downstream, the salt water coming in has the upper hand and it intrudes further into the Delta. Tides can be fast or slow and have lots a rise or a small rise. If you look at a daily tide chart, you can see the changes in depth. The speed of the current is determined by how long the tide will take to get from high to low [outgoing] or from low to high [incoming]. It can take three hours [very very fast] or 7 hours [very slow].

If your boat is going with the current, you will get the best fuel mileage. So in the spring you will "fly" downstream, even on an incoming tide and "plow" upstream, even with the tide.

I prefer going with the tide, but wind can be an overriding factor. However, if wind and tide are going the same direction, it will be smooth water!

BTW, welcome to this forum. Glad to have you here and post any questions anytime!
 
thanks for the explanation. I have been lurking here for a few months now. I am sure I am going to have many, many questions. I have never boated in Rivers, only Lakes.

With the advent of our lakes sort of drying up (shasta and Folsom are in terrible shape) we have decided to start boating in the delta. Of course we are also looking at upgrading boats. We currently have a 21' Four Winns. Hopefully sometime in the next several months we will find a mid 30' express.
 
When does the so called "fresh water" start? I was told around Antioch.
Does anybody know?
 
JMEIRHOFER,
please, please make sure your boat is completely washed and the bilges and trailer inspected for any hitchhikers. Would be greatly appreciated by those who use the delta.Thanks in advance
 
pkjryan - I had an inspection for zebra mussles last fall at my last outing in lake berryessa. I had none at that time but it would probably behoove me to have another prior to sprint commision. My routine upon returning home from the lake (any lake) is to pressure wash everything, including the trailer, then dry and polish. Usually wound up doing the truck too.
 
Fantastic. Thanks for hearing me out and not thinking it was "preaching." The likelihood you would be bringing anything from either lake is small,but, as we see reservoirs at lower water levels I think we will start to see more boaters coming to the delta. Really appreciate the effort put forth by you.
 
You guys help me here if I'm wrong. Another major effect on the salt-fresh division line comes from the pumping of delta waters. As water is pumped out of the delta, that amount of water no longer is available to offset the tidal push, and this is causing (allowing) the salt water to move furthur up the river. This is a major cause of the delta ecostructure degrading, and a reason all of us get involved in the political battle to save the delta. You hear the talk of the periferal canal proposal, and if it is added, will likley allow significantly more water to be siphoned away, worsening the damage we already see.
Jim
 
Jim, you are 100% correct!!!! Did you know that they used to grow crops like corn on Sherman Island? Now the salt content of the water is too high for anything but growing hay and grazing cattle. Some islands have been reclaimed by the state because the farmers can no longer sustain farming them. EBMUD and CCWD must import water from way upstream to maintain the water quality to their customers.

The Mothball Fleet now sits in salt water. All of that used to be fresh water all year long......
 
Flutterby,

You mentioned too much salt in the water by Sherman Island. My friend, a large grape grower here in the Fresno area, and I put my boat ashore on the west side of the SJ about three miles south of Rio Vista to look at a new vineyard that was planted. It turned out to be about 80 acres of new vines planted by Bogle Winery at a cost of probably over a million dollars and their whole water supply comes right out of the river. I wonder if the water gets brackish up that far on occasion and what would happen to the vineyard??? Seems to me the water that far up river would always be fresh....anyone know?

DBH
 
quote:
Originally posted by deltabighat

Flutterby,

You mentioned too much salt in the water by Sherman Island. My friend, a large grape grower here in the Fresno area, and I put my boat ashore on the west side of the SJ about three miles south of Rio Vista to look at a new vineyard that was planted.
<SNIP>
I wonder if the water gets brackish up that far on occasion and what would happen to the vineyard??? Seems to me the water that far up river would always be fresh....anyone know?

DBH

Click to expand...


I'm not sure that anyone can answer that if Benedict Arnold Schwarzenegger gets his way and starts increasing water exports even more by bypassing the Delta. They are planning on installing salinity dams/locks in several places, but from your description, I think the vineyard would be downstream of those that have been proposed. All the more reason to fight his canal plans; not to mention the loss of our salmon runs!
 
I agree with Dave's comments and I fear that Bogle did not do their homework prior to making that particular investment! By September/October the waters get very brackish there. I often will cruise down to Antioch that time of year to get my transom and outdrive clear of the summer slime if my boat has been hanging out off of the lift too long. The salt water cleans fresh water growth off very well!

Perhaps by the time the salt water works upstream that far it doesn't matter to the vineyards? I'm not knowledgeable of growing wine grapes, but I do believe there is a point where they stop watering to allow the grapes to sweeten up for harvesting. Comments?
 
quote:
Originally posted by AbsoLoot

I'm not sure that anyone can answer that if Benedict Arnold Schwarzenegger gets his way and starts increasing water exports even more by bypassing the Delta. They are planning on installing salinity dams/locks in several places, but from your description, I think the vineyard would be downstream of those that have been proposed. All the more reason to fight his canal plans; not to mention the loss of our salmon runs!
Click to expand...


What else would you expect from a governor from SoCal? [:-banghead] They are all biased in favor of stealing the NorCal/Delta water!!!!! [:-banghead] [:-banghead] [:-banghead]
 
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