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looks easy from here
climber
Ben Lomond, CA
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Oct 21, 2015 - 01:11pm PT
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@Reilly-Just saw your pic of Hetch Hetchy. Thanks. Looks kinda grim. Fortunately the plan's migrated upstream quite a bit.
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squishy
Mountain climber
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Oct 21, 2015 - 04:50pm PT
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Shasta update
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rottingjohnny
Sport climber
Shetville , North of Los Angeles
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Oct 21, 2015 - 08:54pm PT
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12,000 gals a day..? That's a lot of colonics...
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TGT
Social climber
So Cal
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Oct 23, 2015 - 07:38am PT
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Boss went to a monthly So Cal water utilities association lunch yesterday.
The speaker was a well regarded meteorologist.
He told them to get their infrastructure ready for 30"-35" between January and March and that it is a sure a thing as you can get with a long range projection.
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Chaz
Trad climber
greater Boss Angeles area
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Oct 23, 2015 - 07:46am PT
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Dam straight!
There was a day when infrastructure kept up with population growth. But not for the last forty years it hasn't.
Now, we're back to doing the Rain Dance, praying El Nino comes to our rescue. Exactly the same way the Indigenous Peoples did it 1,000 years ago.
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pyro
Big Wall climber
Calabasas
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Oct 23, 2015 - 07:49am PT
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I wanna el nino..
I remember last el nino.. we need it
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Ken M
Mountain climber
Los Angeles, Ca
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Oct 23, 2015 - 11:44am PT
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Dams are the WRONG concept for this age. The Dam age has passed.
First, all the good spots are taken. Already dammed up.
Second, many of the remaining spots are now used for other things, like cities.
But far more important, one has to keep in mind what dams actually are: water storage devices.
When you look at it that way, you will quickly realize that we have unbelievably massive water storage devices just waiting for the water to come, RIGHT NOW.
That is the groundwater aquifers (massive lakes) that lay under the ground in the central valley (even in LA!).
The current estimate by the Jet Propulsion Lab via satellite mapping, is that the current unmet capacity of the central Valley is 15 BILLION acre feet.
You don't have to build a DAM THING.
Just to put this in perspective, the deficit is about equal to the entire water consumption of Los Angeles for 25 THOUSAND YEARS.
What really has to happen is to build infrastructure to CAPTURE the excessive rainwater effectively, instead of allowing it to simply run off into the ocean.
In Los Angeles, we are making huge investments to do exactly that.
"Currently, the city captures about 27,000 acre-feet of water, which is used to recharge our groundwater supplies. By 2099, the city aims to collect between 170,000 and 280,000 acre-feet, a huge improvement"
(current yearly usage is about 200,000 acre-feet)
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Ken M
Mountain climber
Los Angeles, Ca
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Oct 23, 2015 - 12:15pm PT
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I am particularly interested in things that individuals can do involving water. It's easy to get caught up in the concept of massive infrastructure that is built by the gov't---and it has it's place. But I also like to look at what people can do.
For example,
1. spread organic mulch. 10# of mulch or compost will hold about 50 gallons of water----just about what the average barrel will hold. Rain Barrels are a popular approach, but mulching all bare ground accomplishes the same thing, and many cities (like LA), furnishes mulch or compost (or both, as in LA), FREE OF CHARGE in unlimited quantities.
http://www.lacitysan.org/srpcd/mulch_giveaway.htm
2. Rainwater capture strip at edge of property (infiltration trenches). a one-foot wide strip of a foot deep of ornamental rock, or free mulch, provides a way for any runoff to enter the water table, instead of running off on the street.
http://www.sccd.org/Infiltration%20Trenches.pdf
3. Permeable driveways instead of impermeable. Again, a pathway for water to enter the water table. Do it when you build it (basically costs nothing extra), or when you have to re-do it.
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Reilly
Mountain climber
The Other Monrovia- CA
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Oct 23, 2015 - 12:19pm PT
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Permeable driveways instead of impermeable.
Ken, are you available to come talk some sense to my wife? She wants a new
concrete one cause it will be "better for resale." Oh, yeah? Maybe some
tree-hugger would want to buy the joint?
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John M
climber
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Oct 23, 2015 - 12:19pm PT
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Ken, In the mountains we have to rake up the pine needles near our homes in order to help protect against fire. Most do leave the needles further away from their homes.
As for permeable driveway.. how does that work. I had a dirt driveway in Yosemite. It was not very permeable because it was so compacted. Water just ran off it.
but I do like your thinking.. In India there has been a resurgence of small earth dams to help capture rainwater and build the water table. It seems to work. Maybe you were the one who posted about this. I saw an article or video about this. Pretty cool.
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johntp
Trad climber
socal
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Oct 23, 2015 - 01:37pm PT
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There was a day when infrastructure kept up with population growth.
I believe the developers take responsibility for this rather than the gubberment (us).
Dirtbags make a bundle and leave the mess behind, as in all the development along the 395 still being served by a 1970s road system.
edit: If they develop a 1000 home subdivision or mega mall, they should bear the responsibility and cost to provide adequate infrastructure, including water supply.
2nd edit: Ken; this is a long thread, apologies for missing your post.
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Ken M
Mountain climber
Los Angeles, Ca
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Oct 23, 2015 - 01:43pm PT
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John, I did post about that, thanks for noticing.
Reilly, have your wife check out this video on permeable concrete:
https://www.youtube.com/watch?v=-iJP7DFt6AU
The way it works is that they use coarser rock in the formulation, so the water runs right through. Underlying the top layer, is a big layer of 2-inch rock, which serves as a water basin, from which the water can drain into the underlying dirt.
The same thing can be done with interlocking pavers, spaced by simple sand.
As for replenishing the groundwater, some are thinking of that:
http://www.scpr.org/news/2015/10/22/55196/uc-davis-maps-farmland-that-can-bank-groundwater-d/
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August West
Trad climber
Where the wind blows strange
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Oct 23, 2015 - 01:56pm PT
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Dams are the WRONG concept for this age. The Dam age has passed.
First, all the good spots are taken. Already dammed up.
Second, many of the remaining spots are now used for other things, like cities.
I'm not keen on more dams. However, if NorCal gets more rain and less snow, building Auburn dam would make sense from a water supply perspective.
Groundwater recharge might make sense in some situations but during a large winter storm, it isn't going to be possible to get all that water into ground. A large peripheral canal could help get water south where it could be put into the ground but I don't know if the politics will ever allow for it.
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Fat Dad
Trad climber
Los Angeles, CA
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Oct 23, 2015 - 05:34pm PT
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William Mulholland was actually an early advocate for underground storage. The loss and salinity increase from evaporation (not to mention how costly and impact driven dams are) are major, unresolved problems. They've tried to address that at reservoirs in LA by covering them in large plastic balls, but that seems feasible only for small urban reservoirs.
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TGT
Social climber
So Cal
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Oct 23, 2015 - 06:03pm PT
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MWD has had floating covers on huge reservoirs for years. So long in fact that a contract is about to be let to replace one of them.
Lake Mathews, Skinner, Diamond are that though. Large amounts of state water system capacity does go into underground storage in years where there is excess capacity.
What will work is driven by local geology/hydrology (which is why in large the porous driveway idea is impractical and ineffective).
The SGV is one big sand pit and an easily rechargeable reserve, but that's a rather rare exception. Most groundwater should be considered a non renewable resource since the recharge times are on the scale of a hundred years or so,
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Ken M
Mountain climber
Los Angeles, Ca
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Oct 24, 2015 - 10:21am PT
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TGT, granted.
Except that we are not taking advantage of nearly all the recharge possibilities. Like the SGV, the San Fernando Valley is very porous, and overlies a great aquifer. Currently, 81 BILLION gallons of rainwater a year runs across that land area, and largely lands in the LA River, and thus, the Pacific Ocean. Actually, the surface area is quite a bit larger, when you count the mountains surrounding the SFV that drain into it.
Granted, huge rainstorms need to be evacuated, but most rainstorms are not huge. Most are under 1", and would be easily captured to a large degree. For example, in 2015, only one rain event exceeded .75 inches of rain:
https://www.climatestations.com/wp-content/uploads/2015/10/lacv2015.gif
According to this graph, since 1921, on only two days of the year are we likely to have greater than a 1" storm, and even then, only 7% of the time.
http://www.climatestations.com/images/stories/los-angeles/LACVPDAY.GIF
We, in LA, have already changed the building codes to require any new building to be able to absorb a 1/2' rain event onsite. It is easy to do, and costs virtually nothing to do in new building. The problem, of course, is existing building stock. And roads.
In my mind, the place to start is the northern San Fernando Valley, particularly in flood-prone areas. Build in absorptive structures in upstream areas, and get rid of the flooding in 90% of the rainstorms.
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Ken M
Mountain climber
Los Angeles, Ca
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Oct 24, 2015 - 11:01pm PT
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here is something else to think about: We are heading into this wet season shortly. What can we do NOW that will impact the capture of that water?
How long will it take to build a dam? 20 years?
However, if they got everyone to go out and spread mulch, that works RIGHT NOW. It is FREE, or nearly free.
A city spreads a million lbs. That will capture 6 million gallons for slow infiltration. If it rains 12 times during the year, that is 72 million gallons. If 50 cities do that, it is 3.6 BILLION gallons per year. Free.
In the 20 years, while we wait for the dam to be built, we can save 72 BILLION gallons of water, to replenish the aquifer. No transfer costs. No labor costs. No material costs.
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Dr.Sprock
Boulder climber
I'm James Brown, Bi-atch!
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Oct 25, 2015 - 03:17am PT
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no rain predicted for 300 years, plenty of time to build dams,
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