Oops - sorry I meant Webster Street. 2100 block.

I complained same story on new house on Newell. It looked like they were putting in a basketball court underground. The hole was gigantic and the water use unbelievable.
Do we need new houses that go to these extremes so badly?

What about the property on University - it will have the same problem. That property design should be put higher up on El Camino where this type problem would not be so blatant.

The pumping does not permanently lower the ground water, only dewaters the hole for long enough to build the basement and water proof the walls install drain etc. Also the amount of water may appear to be a lot, but it is really just a drop in the proverbial bucket. Once the pumping stops the water returns and surrounds the new waterproofed basement walls. Think about how much water soaks into the ground each time it rains citywide. The amount of water that is pumped on one lot (or even 100 lots) is insignificant versus the amount of rain water that soaks into the ground each time it rains. This topic comes up quite often, but the experts all agree it really is a non-issue.

They are allowed to pump this water because there is no problem with it.

There are online studies of San Francisquito creek and the local aquifer it feeds. It is about 1500 feet deep, starting about 15 feet below surface level. It is not lower than usual this year, and the small amount removed by construction of one home is nothing compared to hundreds of square miles of aquifer 1500 feet deep.

Given the connection to the creek - it would be analogous to bemoaning the loss of a million times more water in runoff during the winter. It is a misplaced concern.

The groundwater is fine. In fact with all the lawns, it is replenished regularly with drinking water from hetch hetchy.

If you want to worry about water - focus on the millions of gallons sprayed on lawns, not the thousand pumped out by construction.

Perspective.

Well, if 100,000 gallons are insignificant, then heck - lets all increase our water usage by a factor of ten. It rains so much around here now....

Ultimately if we pump out all our groundwater everywhere in this city and other cities, our reservoirs will have less water that can be stored in them, because rainfall that would otherwise make it into a reservoir has to refill ground water tables. . I am not questioning the after effects of a lower water table, but I am questioning the absolutely barbaric water of fresh water that appears to be taking place.

Why can't the city require new construction to recapture this water and use it for non-potable uses - of which there are plenty?

Actually I read it was 8 to 13 million gallons per basement. If I am going to be busted for letting a little water dribble down the gutter for over spray, they need to save the water. How many toilets could you lush with that water?

The City already has a pilot program for this:

Web Link

The ground water that is getting pumped due to basement excavation is not safe to consume. Could it be tanked and then deposited in a local reservoir or lake? Definitely an idea to discuss. Not far-flung to require a tank (on wheels) to be stationed at a construction site, bring in an empty tank-trailer when the other is full.

I'm sure there is a local hydrologist who can determine where the water should be re-deposited so that the aquifer can be replenished with its own water.

Extra cost? Such is life in the big city...

Shouldn't be allowed, causes sinking eventually. Aquifers DO run dry eventually. This is happening now in Contra Costa and northeast Alameda counties, as the Tassajara Aquifer and others have run dry.

BTW, when Larry Page built his monstrosity on Waverly Oaks Ct, water pipes drained the aquifer beneath his acre and into a storm drain on Bryant for two freakin' years! What a waste! But, he'll pay the price eventually.

Thank you Bill for starting this conversation.

The house on webster just started pumping yesterday. It's very simple - You do not take fresh water and dump it down the sewer! But until there's new legislation prohibiting this, it will not be stopped.

I am thinking of taking some buckets, filling them up with the water, and dumping it on the thirsty street trees.
The water is clean enough for watering veggie gardens, trees, etc.

Also I heard that some of the aquifers in the central valley have gone dry from the agricultural pumping.

Wow. Can I sink one of those pumps in my backyard and have green lawns again? What would a permit cost to dig a basement with an area of one square foot and twenty feet deep?

@Billl

"I am not questioning the after effects of a lower water table, but I am questioning the absolutely barbaric water of fresh water that appears to be taking place."


Are you angered by the creek water running out to sea at a million times higher rate?

It's the same water.

Not drinking water, and it is not causing subsidence or harm to any aquifer. In fact, one home pumping project for a year might lower groundwater by about 1/100th of an inch over the area of Palo Alto. That much water is dumped on our lawns in a fraction of a day.

It really is not a problem. We do not have a groundwater shortage.

@Aquifer -

Then it should be no problem if every home in Palo Alto spent $5K on their own private well tapping the aquifer to keep their lawns green, their pools full, and use virtually unlimited water in their homes, right?

You seem to feel that aquifers and ground water tables are an infinite resource. Well, the Central Valley is already proving you very, very wrong. Now it is just a few isolated communities whose wells are going dry and pumping up sand or nothing at all. In the coming years, as this mega-drought continues, we will find many more cities and towns that face a real crisis.

We will also find that communities such as Palo Alto will figure out ways to capture and reuse water that traditionally disappears out to sea during rainstorms (or reuse non-potable water in their residences).

This is such an obvious way to save so much water that can be used in residential, commercial and industrial uses (I agree that the uses are all non potable), that it is a shame if the City chooses to overlook it and say 'it does not really matter'. It is attitudes like that which cause the average resident to say 'gee, the City (and the State) are not really serious about this, and it must not be a problem if this person can waste this much water'.

Yes, lawn watering should be reduced dramatically - we are in violent agreement. But people wanting to build luxurious basements should NOT be given free passes to take hundreds of thousands of gallons of water and without thinking send them out to sea. The water being wasted on that one property alone would probably water every garden and lawn on my street for the rest of the year.

If you drill a well for landscaping water, you have to meter the water and pay a usage fee to the Santa Clara Valley Water District. For construction SCVWD has decided water is free.

At the Palo Alto Utilities Advisory Commission I've advocated for metering construction dewatering, but Utilities Staff have argued they don't have local jurisdiction. Let the City Council know if you'd like this issue elevated.

As long as construction water is free, the market can’t sort out if other ways to build basements are cost-effective.

@Bill - "if we pump out all our groundwater everywhere in this city and other cities, our reservoirs will have less water that can be stored in them, because rainfall that would otherwise make it into a reservoir has to refill ground water tables"

Really? What reservoir is at a lower elevation than the water being pumped from under a house in Palo Alto? The groundwater here would and could never end up in a reservoir. The only thing "downstream" from Palo Alto groundwater is the bay, which is where it ends up when it gets pumped. Lets use our famously well educated Palo Alto minds on this before we panic.

Thank you Asher - you have hit the critical issue. I will take this to the Council - it seems simple enough to create an ordinance which establishes fees for use of water for construction purposes, but would waive them in the event the water is 'reused' in some way inside the city. The City does have jurisdiction - the Utility Department does not want to be bothered with this issue it seems.

I think the public's right to maintain and protect its water supply is far more important than an individual citizen's need to construct a monster basement. A price on water will discourage this behavior, and/or result in the creation and funding of reuse programs which mitigate the water loss.

Whenever I see water running off a project or the utilities flushing water down the street, it is wasteful. Of course that water should be collected and re-used. If I am expected to only flush my toilet once a day (please don't nitpick, you know what I mean) while other sources let water run off and go straight to the Bay, then something is very wrong and unfair.

I get very upset when I see all the little things I do to save water which make my life that little bit more difficult, while others seem to disregard their wastage as a drop in the ocean. If my little water saving adds up and makes a big difference, then just think what a difference a few hundred gallons being wasted down the street would make if it was collected and reused.

If I can leave my toilet to mellow when its yellow, at least they can keep some of that water wastage too.

There should be an ordinance mandating that all water pumped out from a residential property has to go into a tanker, at the home owner's expense. That water should be used to water the city's parks and playing fields.

So, if I understand, you want water from a construction captured( at some cost) and put where? Who is going to take potentially contaminated water?

Meanwhile the exact same water flows out our creek EVERYDAY and you don't seem the least bit worried.

It doesn't make sense why you would tax homeowners when the same resource flows freely by a thousand times greater every day.

Oh... And for the record, I didn't say groundwater was infinite. I said it was finite - each home pumps about 1/100th inch of water per year.
AND everyday that amount is replenished with irrigation. It's a reservoir. Conservation of mass. When a little goes out and a lot goes in, there is not a problem.

The last home to pump out groundwater on this street was located across the street from this home under construction on Webster. It pumped out approximately 13 million gallons over a period which exceeded 6 months.
A home under construction a few blocks away pumped out 100,000 gallons of water a day. Pumping out a total of approximately 18 million gallons.

Unfortunately, there is no way to capture and recharge this amount of water into the aquifer, unless there was a way to re-route it to Lake Lagunita.

As it is, the water is going into a concrete lined flood channel, with no possible way for it to make it way back into the ground.

The water and moisture give elasticity to our (mostly) clay soils.
It provides nourishment to many trees.
It will take many years for this amount of groundwater to be replaced, since our recharge comes primarily from rain (upgradient) in the hills.

This is just not true. Studies of the aquifer ion isotope types show that near surface level groundwater is very similar to hetch hetchy - our irrigated lawns go into groundwater.

And have any of you measured the water table lately? I have. It's fine. No effect from drought.

If you hate basements, just say so; there is no need to makeup falsehoods about groundwater.

As for capture and reuse - there is no way to do this without storage. If you really want to capture water, A LOT OF WATER you should lobby for a dam or reservoir on the creek or at the point of storm water release.

There is no difference between pumping groundwater for a basement and pumping creek water into storm drains. Same water same aquifer. Not a problem.

Dewatering a single family lot averages about 7-8 million gallons of water
with some lots much higher as reported. Dewatering causes subsidence and
requires recharging of the aquifer with imported water. And we are not
getting meaningful rain. This area has a history of serious subsidence
without recharging. The adjacent properties and trees and landscaping
are especially at risk. Redwoods and Oaks are protected trees under
City ordinance and should not be subject to risk. The trees all over
Palo Alto are under stress now. Take a look at the magic Forest at
Rinconada Park- many of the Redwoods are dying. The closer to the Bay
the more likely dewatering will be required for basement construction.
FEMA does not allow basements fortunately in the flood zone or we would
be having basement construction all over our neighborhoods because
the City would sign off on all of it without a thought about the impacts.
At the recent Newell/Northhampton corner construction after it was covered by local television news the City for the first time used a small portion of the water for landscaping to deflect criticism and congratulated itself
at a Council meeting the next week without indicating how many gallons
were reused compared to how many were sent into the storm drain. The Downtown office projects with two-level basements are approved subject to
the potential for dewatering which is not known until the site is cleared and drilled.

@Aquifer - My argument really is not anti-basement. We have one in our home that was built 90 years ago. I am not residually angry that new homes get fancy new basements. I don't care about it in the least.

My issue is this. Once this water is brought to the surface, it CAN be reused. And it will replace water that we currently take and pay for from Hetch Hetchy for non-potable applications such as park, school, and residential and industrial watering. This water WILL become much more expensive and will be constrained in supply. We CAN build a storage facility - pretty well understood.

I agree with you that ground water because of the elevation in Palo Alto ultimately all snakes its way out to the Bay. But we are assuming we will have continued access to Hetch Hetchy water at very reasonable prices to do things like water lawns and parks and schools. We won't.

We can do some simple things now to reuse easily recaptured ground water and storm water. Stopping this home's million gallon water waste is not the real issue - though cumulatively the city policy of 'free and unlimited water for all new construction' does add up to some very expensive numbers when you do the net present value of what the water we buy to replace this will ultimately cost us. This issue is we may well need to adapt to a reality of orders of magnitude higher water pricing and sharply constrained supply in the very near future. And setting an example for the public by telling the owner of 2133 Webster that he is free to pump a million gallons of fresh but non-potable water into the Bay does a lot to damage public commitment to water saving in our homes and businesses.

What I find interesting is, after drying out the hole to put in a basement with waterproofing on the exterior, how long will the waterproofing last? At some point there will be a leak and unless there's a sump pump installed, it's indoor swimming pool time.

Because of their depth, both City Hall and 525 University pump a lot of ground water every day. When City Hall was being built they got a grant from the Feds because there was so much water present.

In a heavy rain year the C level parking lot in 525 floods.

"everyday that amount is replenished with irrigation."

I call. Prove it.

My concern is broader than that of basement construction, but would also apply to this construction use. Whenever our neighbors are intensively using their wells, as they do during droughts, our garden and walkways sink until we have to replace soil and fix the walks. This is not only bothersome,but expensive. How can this be addressed?

I live near a house that had to pump for a basement. Unfortunately the pumping continued after the house was complete. Most of these houses have a pumping system setup so the water does not flood the basements. The dewatering of the aquifer continues for the life of the house. It just gets pumped into a drain on the property and into the sewer.

I also know of a house on the 2000 block of of Webster that kept having moisture in the basement walls. Eventually mold grew on the sheetrock and the owner closed up the basement from usage. She was afraid for her children.

It's kinda like building a house in a bathtub! At the World Trade Center in New York they had to prevent water from the Hudson river flooding it. They called it the "bathtub"! It held up and prevented a flood when the towers came down.

Once a house (in Palo Alto) has passed final inspection, ground water cannot be pumped to the street (unless there is an emergency)...it is illegal. You can anonymously report them to the city.

re: Wet basement on Waverly (new or old?). If new, then the contractor did not build the basement properly. If old, this would make sense as homes built in the 30's did not have access to current waterproofing materials for subterranean exterior footings and walls.

Let's see now. If left alone, the groundwater works its way into the bay. If a construction site pumps it out and into the storm drain it ends up in the bay, it just gets there a little faster. I agree that if there wer many thousands of people doing this all the time that it might be a problem, but that isn't happening. I think we have bigger issues to worry about.

If the Canopy folks furnished a tanker to take the water, then the water could be used to be spayed onto the trees we so dearly love. Could all you greenies pitch in a few bucks to pay for the tanker truck?

The new completed house on webster still pumps water out of the land. I have seen this with my own 2 eyes. It has a basin near one of the light wells. When the basin collects enough water it has a pump that pumps the water into a drain on the property.

Again, this is a new house not a 30 year old home. The houses built around 15 years ago pump out to the street's gutter. This method of pumping was stopped by the city because they feared it would have too much water going into the sewer. If you walk around old Palo Alto you will see water in the street gutters from pumping. There is one house on the 2100 block of cowper.

And the other point that it is lousy construction to have water seeping into the basement walls proves my point that they should not build basements that require pumping. It's building homes in a bathtub. You cannot stop the moisture on the walls even with water proofing.

Another new house in old Palo Alto that had this problem - they cleaned the walls with bleach and then sold it.

I have lived in old Palo Alto for 20 years and the pumping is all over this section due to the high water tables. They should start building the houses on stilts instead.

My house is about 80 years old and I have a pumping system in my small basement. When we have heavy rains the water table from the aquifer rises from the ground up and can flood my basement. We have a sump pump that pushes the water out of the basement.

Since living in this section of old Palo Alto I know more about rising water tables than I want to know!

Some of the water in the streams is actually bay water that comes in at high tides. It is a mix of water types.

My take is that water pumped from a house construction is all regular water that has not been treated and is suitable for the garden and trees.

How irritating is it that we are carrying buckets of water outside and watering individual plants with treated water.
The city should be deploying a tanker to the residential sites so the ground water is collected and used in the parks.

Here is what I have learned through multiple sources

1) The property is still pumping massive amounts of water around the clock. We may well be talking 1/2 million gallons per week of water pumped out for this property alone. I have no clue how long this will go on.

2) The City's newly assigned person in charge of handling water waste complaints has not called me back despite two days of repeated calls to his office.

3) I did have a thoughtful conversation with a City Council member, who did express a concern for a medium/long term plan for ground water storage and reuse in the context of the drought, but he did describe the current situation with 2133 Webster and the water waste as 'de minimus' - meaning it is irrelevant. Given this water can be reused presently, I am not sure I agree with him. But I do hope the City is serious about a plan to reuse all this available water sooner rather than later.

4) On NextDoor, another person involved in construction and pumping water on their property, called the City to offer to allow their water to be reused. It took the City 5 days to come out and talk with them, and so the majority of the water is still being dumped in the storm drain.

5) It seems the Pilot Project referenced earlier for reuse was a one time thing designed to issue a press release - the amount of water recaptured was very minor, and there are no plans to continue the program.

There are concerns that massive pumping of groundwater can effect land and building settling and also large landscaping like trees. I am not a hydrologist nor arborist, but it seems to make some sense. The one thing that the Central Valley experience has taught us is that we do not really understand how aquifers work completely, and any assumptions about how they will or will not continue to work should not be assumed to be the gospel truth.

I still feel strongly that the City should require new construction sites to store pumped ground water on or offsite as much as possible and then facilitate its reuse. Perhaps it is impossible to reuse it all, but it should actively encourage this, and not suggest we are worrying about minor things, or fail to respond at all. This will reduce our consumption of potable water that is in short supply, and save us money in the short, medium, and long term.

And the PR implications of this are probably equally compelling. When you are asking people to change their lifestyles, but seem less than urgent about changing how the city does business, you shoot yourself in the foot...

Pumping 100,000 gal/day, as one poster alleges, means that a 34-foot column of water 20 ft square was removed each day. This is ludicrous - why don't people try a sanity check on the so-called facts they promote? Basically, pumping groundwater for construction is routine and not an environmental waste.

If the argument is that we should truck the water to some other location so that it can be used, what about the environmental effects of producing the fuel that the tanker will use? Everything is a trade-off. Where is the analysis of the cost of reclaiming the water?

Too many educated (?) people with too much time on their hands.

Come on, what are you doing? Waiting for the city to do something. Then you will get more arguments. Somebody need to get this organized and collect some $$ to pay for the truck.

Anyone who thinks our current drought is not a big issue needs to read up a bit more. Stanford scientists are cautioning that we may be in for a long drought, so it's time to stop thinking that next year everything will go back to normal.

Web Link

Another great source analyzes drought conditions in the far past that went on for decades, and even centuries.

Web Link

I understand the arguments about how much runoff goes into the Bay versus the amount of water pumped out for basement construction, and I think it's time we started figuring out how to capture and reuse both! The obvious first step is gathering the water that is being gratuitously pumped out of the ground and into the Bay simply for one property owner's desires.

Tell me, why would we NOT want to capture this non-potable water and use it for appropriate irrigation, car washes, etc? We need to protect all of the water resources we possibly can. (And if the water is possibly contaminated, all the more reason we should capture it and treat it, not just dump it into the Bay!)

"Pumping 100,000 gal/day, as one poster alleges, means that a 34-foot column of water 20 ft square was removed each day. This is ludicrous - why don't people try a sanity check on the so-called facts they promote?"

Glad to. 100,000 gal per day / 1440 min per day = 69.44 gal per minute. Nothing extraordinary about that, easily within the capability of even a 70-year-old electric pump design.

And thanks for the graphic image of the magnitude of this waste of water.

Perhaps we need to raise attention to this matter at the state level. Given the Governor's reduction mandate, there is no excuse for ignoring this issue...

The economics of this are pretty simple @Jack. I can buy a refurbished gas truck that would otherwise carry gasoline to retail stations, and repurpose for water. 10,000 gallon tank for $25K or less. Each truck if filled up twice a day every business day would save five million gallons a year. At the one cent per gallon current market price for commercial water use in Palo Alto, that is $50K, which would probably pay for the driver, depreciation on the truck and gasoline. You could also probably charge the homeowner for this as well. We do not need to repurpose all the water these projects generate, but 5 million gallons is a lot more than a drop in the bucket, and since water prices are going up and fast in the next few years, the economics will be even more attractive. Scale it up by adding trucks - not so hard really.

I will be glad to work with you or the City on the economics. It can easily work. I will bring in hydrologists and arborists who will tell you this is a very bad idea to take this much water from the ground. And when it hits the front page of the Daily News and Post and Mercury News, and when the City's Water Police (who will not return my calls) start issuing $500 fines for wasting a few dozen gallons to average homeowners, people will get very upset, and the spotlight will be turned on the City. I thought the City was going to be slowing development somewhat after the last elections - but more commercial buildings, and large residential homes with two level basements and indoor swimming pools on the second basement level are not going to slow water use.

2133 Webster will probably spew out 5+ million gallons of water over the next 3-4 months that could be reused in the City at a very small expense. I think right now the City Staff has made their own internal decision that they do not want to address this issue. This is unfortunate. I think public pressure is what is required. I hope they take the Governor's mandate to reduce water usage in any way possible by 25% seriously, and not just issue press releases, send us letters, and build cool new apps for our iPhones.

Some reading for laymen on our local aquifer at the link below about the groundwater under Palo Alto. Too much pumping for the fruit trees in the last century caused up to 14' of subsidence in the ground level as the aquifer compacted. And, when that happened our groundwater's aquifer doesn't pop back up to hold as much water as it used to thanks to its high clay content.

About the mid-1960's urban pumping started to overtake agricultural pumping here. In Santa Clara County, we now use more ground water for urban use then we ever used in the old agricultural days. Thanks to surface water imported from elsewhere to recharge our groundwater we have enough groundwater in Palo Alto to back up our Hetch-Hetchy supply to blow on those basement projects but maybe not for long if we lose our quotas of surface water imported from elsewhere.

Web Link

I have over 40 years of living in northern Palo Alto. Lived through the bad drought in the 1970's. Interesting experience. I can't let water run anywhere I travel while brushing teeth, know how to stop old plumbing leaks, and for decades after still feel guilty taking long showers. This time around I'll learn all about drought resistant plants.... and maybe go over to my neighborhood basement pumper tank and tap in a spigot for my watering can! (Or just fill the can at the storm drain where the dewatering line empties at night. A small moral victory.)

A study session on groundwater would be helpful. Allowing construction to pump thousands of gallons of water into the storm drain when irrigation is restricted does not look good for anyone.

If there are no negative effects from pumping the shallow aquifer and the water is good for irrigation, then we should promote drilling shallow wells. If there are negative effects from pumping, then we should either price the water or ban the practice. If the argument is there are no negative effects from just a few sites pumping, then we can ask why we preference pumping for new construction versus existing landscape and trees.

We should try not to jump to conclusions about what to do with the pumped water (store it, truck it, dump it, etc) or whether pumping has anything to do with allowing basements. Those are technical and economic questions once we've set the policies and the water price.

Engineer: The calculation of gpm is elementary and misses the point entirely. A 20x20 ft hole in the ground (nominal size) is not going to produce daily seepage equal to a 34-ft water column. (I'm speaking of a construction hole in Palo Alto, not some hypothetical worst case.)

Bill: Your estimate for the cost of a used tanker is on the low side, by a factor of about 2. Regardless, unless you're planning to go into the water transportation business, you won't be buying any capital equipment. Instead, you'll pay someone to provide the labor and equipment each day.

Do you have a buyer in mind who will pay one cent per gallon? Unlikely, but if so, using the SWAG figure of 100,000 gal/day, the water is worth $1000/day. I do not believe you can get a quote to move 10 tanker-loads per day for less than $1000/day. If the service is required 24/7, you will also have to pay time-and-a-half and double time. If the service is to be only during normal work hours, then on-site water storage up to two days' worth (200,000 gal) is needed.

To be clear, I am not against conservation or reclamation of the water, but the issue has not been quantified. Basically all we have are seepage numbers pulled out of thin air and no cost analysis of the proposed solution. (Cost analysis is a basic skill for those in the business - it's more than simple math but not much more.)

The price is already set. Agricultural water rates from SCVWD charge $19/acre-ft.


The hypothesized (excessive estimate ) of 6million gallons dewatered for a project is ...17 AF.

Total water cost: $323.

Mice nuts. In fact, it is often much less water for many projects. If you time it with the end of the dry season, there may be no dewatering at all.

You guys couldn't truck away a single tanker for that money. How are you gonna make that work economically? Heck for $323 I doubt SCVWD would even roll a truck to meter the problem.

Perspective.

Ah yes, but we don't pay "agricultural" rates do we? What does it cost me to flush my toilet in Palo Alto? What does an Acre Foot cost me to water my lawn? That is the number we should be working with.

I think you'll find that groundwater from construction dewatering varies from murky grey-water to EPA Superfund site water . The ag rates are the best price anyone would value this water.

Comparing it to your drinking water you use in your household is a very different quality, delivery, reliability and pricing.

If you read this whole thread, you'll see the only use anyone could dream up is watering parks and trees.

Perspective.

I could easily replace over 80% of the water I use with this ground water so I figure the correct rate should be what I pay for Palo Alto water. What does an acre foot of Palo Alto water cost??? That would be on the order of 300,000 gallons. We all should have two water sources, clean drinkable water and recycled/ground water coming to our homes.

@ Midtown - Nothing is stopping you from drilling a well, go get the permits and hire a contractor. If you used 80% less water, everyone would benefit.

Reusing our own gray water is becoming a serious consideration. So much water from laundry, dishwasher, showers, could flush toilets at the very least. The costs of installing a grey water system should be something we could get rebates for.

At another level, new homes may soon be required to have these as well as hotels.

On the business level, there has been posts from someone on Town Square who is trying to set up a business to use reclaimed unpotable water for lawn maintenance so at least one person things this is a viable option.

A system of desalination could also supply a secondary water delivery system to at least coastal communities.

Water will become the new gold for California. Pricing at various tiers and other options will become affordable as clean drinking water becomes more precious. With the California population expansion continuing, looking into efforts other than just water conservation is going to have to be looked at seriously.

"Engineer: The calculation of gpm is elementary and misses the point entirely. A 20x20 ft hole in the ground (nominal size) is not going to produce daily seepage equal to a 34-ft water column. (I'm speaking of a construction hole in Palo Alto, not some hypothetical worst case.)"

It is you that is hypothesizing. I speak from experience.

Common wells yield much greater volumes from far, far smaller collection areas. I have personally watched a three ft diameter 30 ft deep hand dug well sustain 900 gpm in an area with a climate much dryer than Palo Alto's.

"What does it cost me to flush my toilet in Palo Alto?"

About a penny if low-flush. Maybe 3 cents if old-fashioned.

"What does an acre foot of Palo Alto water cost?" (400 units of 750 gallons)

About $2000 at tier 1 rate, but you'd most likely be in tier 2 so call it $3000.
Takes me a decade to use an acre-foot, but my crops are tiny -- mostly zinnias.

I'm surprised nobody has suggested banning beef sales in Palo Alto.

Yesterday i went to the roaring water going down the sewer and filled up some buckets. The buckets filled up in about 2 seconds! The water is beautifully clear.

There was also another neighbor fillings up some buckets too.

I used it to water some dry and thirsty plants on my property. I know the water is clean because a friend of mine captured the water pumping from the house on Bryant and it tested very clean. She also drank it. This was a few years ago.

It almost made me cry to see so much water going down the sewer. I don't have facts and figures about the cost of this water. Just looking at it roaring down the sewer while some nearby magnolia trees are bone dry just makes no sense.

Tell all the local tv stations. You can email the news stations and/or the individual reporters.

This water is NOT going down the sewer as several people have claimed. The sewer pipes take waste water from your toilets and sinks and deliver it to the water treatment plant. Water in the street goes down storm drains and into creeks that take it directly to the bay. These two water systems were separated decades ago. If you want to address the issue intelligently you really should show some knowledge of the situation by using the proper terminology.

I do agree that these sites should be setup to make the water available to anyone who wants grey water free. The cost to add hoses and a fill valve to load a truck is cheap.

But if would have to be pretty fail safe, so that left unattended the construction site is guaranteed dry. Probably a simple engineering problem.

We can ignore the effects on adjacent structures and landscaping and trees from even a temporary draw down of the water table from dewatering, viewing it as simply collateral damage to allow basement construction, OK I get that; the water table is fine and we can continue indefinitely to import water sufficient to recharge and maintain the water table to avoid subsidence despite the drought, no problem there; and we can reuse some of the water which is pumped out. So for some there is no problem here. But for some reason trees are dying all over Palo Alto. Do they know something we don't know? Uncontrolled dewatering looks peculiarly like uncontrolled
underparked office construction Downtown. The trees are telling us something.

I am surprised that no one has brought up the re-use of the sewage treatment plant's treated water that goes into the bay. This water is fairly close to, if not, sterile and if we are really interested in recycling all sources of the water we use then we would be looking at every house and building having a secondary water system using this water to flush, shower, launder, water our plants and lawns and wash our cars. Costly? You bet. But in many areas of Germany this is exactly what they have - two separate water systems - potable and recycled.

Last year I watched a construction project on Bryant pump water 24 hours a day for MONTHS, many months. This is insane to drain the aquifer so people can have these basements. When I bought my first house in Palo Alto we always looked in the basement (which were really basements, not fully finished living space) to see where the high water mark came during the rainy season. Hopefully those days will come again. I bet the people with huge basements who have waterproofing failure will be complaining loudly.

Seems that we all agree that groundwater pumped from a construction site has a value, but disagree on whether the value is high enough to merit reclamation of the water. So why not let the market decide? Offer the water for free to all comers and see if the economics can support private removal and reclamation. A poor outcome IMHO would be if well-meaning but uninformed "conservationists" were to pressure the city into setting itself up in the groundwater reclamation business.

To the Engineer who speaks from experience:

Please focus on the issue of seepage in a construction hole in Palo Alto. For consistency, let's exclude the Baylands and hills.

1) At what depth do you expect to first encounter measurable seepage? (It will vary, of course, on how much rain we've had, so let's say we're talking about the ground condition today.)

2) How deep would you estimate is the excavation for a typical basement? (Single-level basement, again for consistency.)

3) How deep is the water table?

Although you may have personally observed a three-foot diameter, thirty-foot deep, hand-dug well sustain 900 gpm in an area with a climate much dryer than Palo Alto; that is no more applicable than the fact that I have contracted for 1200-foot wells with similar output in the middle of the desert. Or that I personally witnessed someone in Woodside strike water at a depth of only four feet. (He was drilling holes for fruit trees and cut through his water main.)

Thanks.

I built a house with a basement in Palo Alto, so I can answer some of these. They are in geology reports filed with most building documents.

1) At what depth do you expect to first encounter measurable seepage? (It will vary, of course, on how much rain we've had, so let's say we're talking about the ground condition today.)

About 12'- 20' below grade. There is a layer of clay on top of a layer of clay-sand that runs different depths in Palo Alto. These numbers are not uncommon in town. The seepage is extremely low even half a foot above this level. Clay transmits very little water.

2) How deep would you estimate is the excavation for a typical basement? (Single-level basement, again for consistency.)

Using a typical design that has the first floor 1' above grade, and 8' ceilings below grade, with a 3' concrete slab, and 6" working slab, you get an excavation level of ~12ft depth.

3) How deep is the water table?


The aquifer starts at the sand level - as above it is something like 14' - 20' down and varies by location. However, if you drill such a hole all the way into the sand, and wait a while, the water level rises to 11.5ft (as of last week) due to hydrostatic pressures. (even though this is above the clay-sand line) Different times of year, this water level will range from 10 - 13'.

If you are pumping from the clay layer, very little water will come out. If you are pumping from the sand-clay layer, more, and if you are pumping from the sand layer, the water seepage can be high.


If you build the basement in Sept - Dec the water table is the lowest, and you need pump very little, or none at all.

I left this alone for a couple of days. A cold interfered.

We may well find ourselves in a a situation very shortly where will not have access to all the Hetch Hetchy water we need. And/or the price rises dramatically. In either case, the value of the ground water will rise equally dramatically.

The City is moving in many directions to become more 'green' - for example, now requiring all new houses to be 'solar ready'. It seems like it would be a very small investment to truly begin to investigate how to incorporate water reuse into the equation for a sustainable water solution.

Jack, I am sure my numbers on trucking and transportation are a bit off - and maybe at the current price it may be a marginal breakeven proposition. But if the price of water goes up 5x (not an impossible scenario for volume users), I am sure someone could build a very profitable business pumping out free groundwater and reselling it. Even better if the city got ahead of the curve, and 'nudged' the market along in a positive direction. The day the Governor bans all lawn watering is the day someone buys a truck and starts making money hand over first.

None of us - PhD's, wildcat drillers, or arborists know exactly where we are treading here. The rules for what we think we know on water may well be completely wrong as this drought continues. So, we had better start conserving not just potable water - but ground water as well.

And the PR aspects are just the worst of all. I really do believe that California could learn to make do with 50% less water than they use - but when they see things like this that appear so wasteful, their willingness to sacrifice may well fall short of what is required.

I once inquired about having some foundation work done on my home. The company (located here in Palo Alto) immediately tried to talk me into having a basement constructed. I felt this guy was using hard sell pressure with me in his sales tactics.
I told him that I didn't want a basement. I then told him I lived on a small lot with a really high water level. He continued to pressure me. I told him that the homes on my street were close together; and I would not want to damage my neighbors homes.
He continued to try to convince me.
I told him I didn't need the extra space.
He told me that I SHOULD do it to increase the value of my property.
I told him that I was leaving the home to my son, and that he didn't want a basement either.
I told him that I did not want to give my son a home, or sell a home with a potential for failure down the road.
He would not give up.
I felt like I was at a car dealership.
Finally I got out of there (exasperated) by telling him that the cost was a factor, and that I would have to think about it.
The point I am trying to make is how easily people could get pushed into something like this.

To My Thoughts:

Thanks for providing the info. Two points in particular:

1) A single-level basement may not be much of a problem. A permit for a two-level basement should be contingent on minimal waste of groundwater.

2) An incentive of some sort could be used to promote construction during Sep-Dec.

To Senior Resident:

I agree that people can be pushed into things that sound good. So we should be diligent (and neutral) as we gather the facts about water resources and usage, and then we can build a plan that actually is solid.

I love the idea of a TV station filming Palo Alto residents with buckets in their hands or pots on their heads walking water supplies from dewatering ops into storm drains. Right up there with the Californai Avenue glass shards in the sidewalks hilarious visuals.

Web Link

A great article about what we can do to survive the MegaDrought as a state.

No dewatering probably falls under Idea 2.

Bill -

Thank you for highlighting the issue of water conservation in Palo Alto. While this thread has been primarily concerned with groundwater losses due to construction, the "elephant in the room" is the drought that may continue for several more years. More likely than not, harder times are coming. Snowpack in the Sierra was 5% of normal until last week's late season storm and now it is only 8% - with no more precipitation expected until the fall.

For reference, water from a coastal desalinization plant costs about five cents per gallon, and since ocean water is essentially unlimited, we can take that cost as being the upper limit of value.

I agree with your summary statement: "It seems like it would be a very small investment to truly begin to investigate how to incorporate water reuse into the equation for a sustainable water solution."

Here's my start - feel free to modify:

1) Identify water sources (precipitation, aquifer, Sierra...)
2) Identify major water losses (construction holes, creek outflow...)
3) Look for ways to reduce consumption (watering the sidewalk...)
4) Look for ways to prevent or reduce major water losses

Discussion of costs, which can get in the way of a good idea, can be held until later. (We'll still want to bring up some numbers now.)

Changing the subject, apparently Pleasanton has recycled water that they give out for free. And all new homes built in Livermore have 2 water systems ( I may be wording this wrong). One is for recycled water the other is for drinking water.

Web Link

Here is the presentation that describes the Pleasanton program. They recycle millions of gallons per year and have residential and commercial users. Won several awards, and it is heavily used....

@Bill Glazier - Palo Alto already has a water recycling program:

Web Link

"The Regional Water Quality Control Plant Water Reuse Program has historically brought a reliable, sustainable and drought-proof supply of water to the South Bay and Santa Clara County. The treated water is suitable for landscape irrigation, commercial and industrial use and habitat restoration. This program serves the cities of East Palo Alto, Los Altos, Los Altos Hills, Mountain View, Palo Alto and Stanford. To date over 10 billion gallons have been reused since 1980! (Which equals the amount of water used by approximately 2,500 families of five per year for the past 23 years)"

@Slow Down. Well, let's peel back the onion here. That is 10 billion gallons over 35 years, spread across many cities. I estimate over the same time period, Palo Alto alone has wasted over 5 billion gallons by allowing dewatering of residential construction sites. Probably Palo Alto has wasted more water from dewatering to build big basements than it has saved from its part of the recycling program.

The point is that 1) our reuse potential is substantially higher than the current program, and 2) the waste of dewatering for our basements is in fact staggering.

We need to reuse far more reclaimed water, and we need to stop this insane pumping of our ground water for something that frankly is a luxury item - the need for 1500 square foot basements.

@desert had some very simple and good ideas - no basements beyond a maximum depth, and no construction during periods of high water tables (if people can't wait 6 months to build their dream home/basement so they don't need to pump 10M gallons of water out, then they might be out of luck).

The good news from my reading of the SCWVD reuse program is that their is already a holding pond in the Baylands for recycled fresh water, so that can be reused...... we could do something similar to Pleasanton in less than 6 months if that were the case...

I've been told by the Department of Public Works that they have agreed with the homeowner at 2133 Webster to provide a water storage facility on site which will enable street sweepers and trucks to reuse the water. It should be in place by the end of this week! This is similar to what they did on one earlier similar project. It will not reuse all the water, but will provide the opportunity to reuse as much as possible. I do not know if it will be accessible to individuals as well as the commercial trucks - but it is a good start, and I appreciate that the homeowner was willing to do this, and the City encouraged them.

I do think that we need to thoughtfully revisit this issue of dewatering in many contexts, and I believe that water reuse is going to have to be a big part of our future water strategy as a community. People on this thread have already come up with some interesting ideas, and I think as this drought continues we will be forced to rethink how we acquire and use water.

@Bill - You keep saying it is waste, but it isn't waste because 1: it was never going to be used in the first place, 2: it isn't gone, it just being moved. The only thing you could argue is waste is the electricity used to pump the water. If you banned basements, we'd be no better off than we are now. You'd just feel better about unused ground water.

You might like this though, Stanford Prof Buzz Thompson talking about water pricing, and some innovative ideas like harvesting the methane from waste water to power the recycling.

Web Link

Speaking of pumping water, I thought it might be of interest to some here to know that Raindance started operations in Palo Alto today, and is watering residential landscapes on Channing, Edgewood, Forest, Chaucer, Hamilton and Dana as we speak. Raindance is a monthly subscription service that trucks recycled H20 from PA's H20 treatment plant to homes and then irrigates yards/landscapes with it.

Raindance can be found on Facebook!

Coming soon, new hotel replacing Ming's: "We need to dig deep underground for the hotel parking lot. That means draining all the water underneath this building and dumping it into the Bay." -- Web Link

It takes about 5 years for the groundwater under Gilroy to flow down to the Bay (factoid from a USGS report, IIRC). So, yes, dewatering a basement is just moving the groundwater a bit faster to the Bay to join the wastewater runoff we pump to the Bay everyday. As water penalties start to bite this summer.... every drop does help, so good news on that Webster dewatering resuse.

The local leader in reuse of "wastewater" is Sunnyvale. Palo Alto is quite a few years behind our southern neighbor.

I got an email today from the City's Recreation Department in charge of fields, saying that field watering was going to be substantially restricted this summer, and some 'ornamental' grass would be left to die.

I immediately pointed them to 2133 Webster, where we can retrieve enough water to water many fields around town at low to no cost.

I will follow up to make sure they do.....

Just watched a story about the dewatering in Palo Alto on KTVU channel 2 news.

The reporter was on Webster street and another location.

She was in front of the locked valve on Webster. The city utility spokesman said if you want the water via the valve you need to have a pickup truck with a barrel in it and the city will unlock it.

I have not seen any trucks getting water from the valve on Webster.

The news story will probably be repeated at 10pm.

Just another thought about the KTVU piece...

The city utilities spokesman did not say anything about city plans to use the water via the valve. He only told the reporter that you can obtain the locked water via the valve if you call the city and you must have a water truck or a pickup truck with a barrel in it.

Yup we all have a water trucks!

Web Link

That is the link to the piece on KTVU that ran tonight. Basically said 3 sites in town are pumping 70,000 gallons each per week into the storm drains. Said it was an insane waste of water. Phil Bobel, City Public Works Assistant Director, was interviewed and said it looked bad, and did indicate they are 'looking' for ways to reuse the water. They have required the residences to put in place a device which would allow someone to come by and load up a truck or large container.

This on the same day I received a letter saying water rates were going up, and then an email from the Rec Department saying they intended to substantially cut back watering of fields this summer...

So why aren't they collecting this water and using it to water our parks and fields?

So why are they putting up our water rates?

If they were putting up our rates to cover the charge of collecting this water and using it to water the verges, the parks, etc., it wouldn't be such a bad thing.

I live smack between two of the dewatering properties now lowering my local aquifer's water level. If my trees start dying this summer (or thanks to aquifer subsidence when the drought breaks and I get never before pooling of surface water) do I sue the City and/or the dewatering property owners to fix the problems created directly by others' actions?

The funny thing is thanks to almost fifty years experience living here and watching in heavy rain years hoses come out to curbs to drain basement sump pumps in the mostly still 80+ year old houses with tiny basements I know it will take 3-5 days for water under the highground dewaterer to flow to the lowground site since that's the way the aquifer here flows down to the Bay ..... so the Highgrounders are really pumping for both..... and our nearby neighbor with the well might have to drill deeper to keep his well alive.... a well drilled around the time of the last big drought.

Oh, yeah..... as long as groundwater laws are the Wild West, heaven help us when the well drill rigs start pounding.

The only way this building practice will stop is to ask our city to disallow residential basements to be built in areas with known high groundwater. Even though there is some seasonal fluctuation of this flow (depth and path), most areas are fairly well know.
The problem over these past years has been that realtors are telling prospective buyers that they can build basements out to the lot lines of these small properties. Many of these buyers may be unfamiliar with the hydrology and geology of our area. We live on a peninsula with the sea on one side and the bay on the other. Our groundwater is replenished by rain activity in the mountains, and insignificantly by landscape watering.
Since we are in extreme drought, this would be a the perfect time for the city to suspend basement dewatering permits until we are out of drought. During this time, the re-study this practice which (somehow) is allowed in the Green Building Code.
We really don't know what the future holds in regards to the amount of rainfall in the mountains, so we should preserve what we have from here on.

In 2008 an Old Palo Alto homeowner brought this issue to the city.

The city did a study and rejected any end to the dewatering and basements.

This issue was was a result of a basement being built on 2164 Webster street.

The Palo Alto Weekly wrote an extensive piece about this story on 5/28/2008.

The story is still online via Palo Alto Weekly

Web Link

P.s. I think the current project on Webster street may be a 2 story basement requiring more dewatering.

And the 2008 city study for a basement ordinance is still available on their website. tt is a 56 page document and takes awhile to load.

Web Link

Maybe that means that there is actually plenty of water, to the point that you just need to excavate a few feet to find thousands of gallons of it... and that this all drought story is blown out of proportion.

Bill Glazier's link above to the KTVU story was run several times during this morning's broadcast too.

It seems that they feel this is fundamentally wrong too.

Why should I let my lawn go brown when all this water is being wasted let alone curtail showers and laundry, are fair questions that somebody needs to answer?

@Resident - because it isnt the same water? And the stuff getting pumped was never going to end up in your shower? And it isn't being wasted it is just being moved?

NBC Bay Area TV News was out at the Webster site today. They came at the same time the City brought out one of their tank trucks to load water that will be reused in the Palo Alto Landfill (Mike Nofizger with the City was helping to facilitate since he was involved in the original pilot project earlier this year). It seems that the City will be using this water extensively to help 'damp down' all the dirt they are managing at the landfill. This will replace otherwise potable water they would use in its place. The Landfill Project Manager was there and he said he was going to try and bring his trucks (he has many of them - 3900 gallons) over as much as possible. He suggested there were many opportunities for reusing water in the City, that they could have tanks coming to Webster constantly to load up and reuse water. It takes 10 minutes to load the tank - they could reuse a very large percent of he water

I also told Mike this water needs to be reused to help Recreation water the fields this summer....

Now the challenge is to get the City, at a minimum, to pass an ordinance mandating reuse of water for all dewatering situations in the City of Palo Alto. Then the issue of whether drywells can be created to return this water to the ground/acquifer can be evaluated.

The PR will only get worse for the City, and so I hope they will be a bit more receptive to acknowledging this is more than just a minor situation.

It appears that 2133 Webster is another one of these double depth basements, where the water will need to be pumped for a very long time.

NBC Bay Area TV News was out at the Webster site today. They came at the same time the City brought out one of their tank trucks to load water that will be reused in the Palo Alto Landfill (Mike Nofizger with the City was helping to facilitate since he was involved in the original pilot project earlier this year). It seems that the City will be using this water extensively to help 'damp down' all the dirt they are managing at the landfill. This will replace otherwise potable water they would use in its place. The Landfill Project Manager was there and he said he was going to try and bring his trucks (he has many of them - 3900 gallons) over as much as possible. He suggested there were many opportunities for reusing water in the City, that they could have tanks coming to Webster constantly to load up and reuse water. It takes 10 minutes to load the tank - they could reuse a very large percent of he water

I also told Mike this water needs to be reused to help Recreation water the fields this summer....

Now the challenge is to get the City, at a minimum, to pass an ordinance mandating reuse of water for all dewatering situations in the City of Palo Alto. Then the issue of whether drywells can be created to return this water to the ground/acquifer can be evaluated.

The PR will only get worse for the City, and so I hope they will be a bit more receptive to acknowledging this is more than just a minor situation.

It appears that 2133 Webster is another one of these double depth basements, where the water will need to be pumped for a very long time.

Talk about a very long time to dewater: when Larry Page's home was being built at the end of Waverley Oaks Ct, long, long pipes drained water from the aquifer under the basement down a gutter on Bryant to a storm drain on the corner of Bryant and California for TWO SOLID YEARS! No one said or did anything, nor was there any media attention. What a dreadful waste!

Now this is making the local and national news-- there was an article about the stupidity of California governments and residents during an historically severe drought in the Wall Street Journal and the New York Times last week.

Between this and the suicide cluster, Palo Alto looks like the last place anyone should live! We are an embarrassment to ourselves.

Tonight I saw this story on KRON 4 news. The reporter was live outside another dewatering site on waverly street.

The owners of this property were nice enough to install a valve that is open . The valve was not hidden behind a lock, wooden structure and chain link fence! It appears that it is open to neighbors to get water.

It's too bad the owners on Webster street are not that considerate and generous to their neighbors. It always seemed funny that the water is safely guarded to go down the storm drain.

Homeowners in other states have reported that their foundations and basements began to crack and leak after severe drought when their clay soils dried out.
Web Link
Web Link
We can expect the same thing to happen to the homes in our community, since we are allowing some people to intentionally pump out the groundwater under our homes to build basements in areas with known high groundwater.

A home under construction on Harker started pumping water for a basement a couple days ago. Based on how quickly a neighbor filled a 5 gallon bucket, water is going down the storm drain @ 75 gallons per minute which is 108,000 gallons per day. That's 14,400 cubic ft per day, or 144 CCF per DAY. If an average household uses 10 CCF per month, that's 14 months worth of water wasted EVERY DAY, or a month's worth of water for 14 homes. I was told the pumping will continue for 4-8 weeks. That would be nearly 400-800 home' monthly water down the drain.

It's time for an immediate moratorium on basement construction that requires ground water pumping, followed by a review of zoning and construction regulations. I favor banning basement construction if if requires ground water pumping. Until recently, Palo Alto didn't allow basement construction, but with skyrocketing property valuations and lot coverage limits, new buyers pushed for basements to increase floor plans while staying within the lot coverage requirements. I think we need to put a stop to this now.

If you agree, please write the letter to the City Council.

@SS - what do you propose be done with water under a homeowner's house after a basement ban? It just sits there unused anyway.

If there really is all that water sitting underneath Palo Alto, perhaps we should get some wells dug in the parks to water them and then we can all stand in line with our buckets and get some to water our own lawns.

When the drought gets real bad, we may need them to flush the toilets too.

OK, stupid comment, I know.

But at the same time I seriously question why ground water is being removed and put in the Bay. The ground water should really be staying in the ground to keep whatever it does to our ground bed safe. If it is being removed then something is not as it should be. It seems to me that keeping it in the ground albeit at another level makes sense. So yes, get tankers to fill this water then use it to irrigate parks, lawns, etc. This is basically returning the water to where it needs to go, back into the ground.

@Resident You can dig a well right now, anyone can. Just get the permits. Even if your neighbor drains for a basement, you can still get your well water. It isn't worth doing though, it is cheaper to just get rid of your lawn.

@Slow Down

Groundwater is an essential resource. Trees need water, and it's best for their health - and our safety - when their roots grow deep. When the water table drops, the roots grow horizontally seeking surface water. That buckles sidewalks and roads, and increases the risk of trees falling during wind storms.

Ground water also prevents subsidence of the land around buildings. Subsidence can damage foundations and walls, and when at it's worst result destroy entire buildings. Look at what's happened to the islands in the Sacramento Delta and agricultural land in the San Joaquin valley as a result of persistently high pumping over decades.

Deserts are dry not just because it rains less there, it's also because there is little or no groundwater. When it does rain the ground is either so packed (like pavement) the water runs off in arroyos to rivers, or so porous it very quickly drains until it hits clay or bedrock. Do you want Palo Alto to look more like Palm Springs or Las Vegas? I sure don't.

@SS - That pumping some ground water will turn Palo Alto into Palm Springs is beyond an absurd proposition. You are confusing aquifer pumping the central valley with ground water under a house. The temporary removal of a few hundred cubic feet of ground water is irrelevant to the ecosystem, and won't affect yours trees either because the pumping is localized.

You can go back to posts in these forums 4-5 years ago complaining about the same things. Except now we can go back and see the tree death claims were wrong. Unless you were going to plant a tree in your basement, there is no issue except people's feelings.

>> The temporary removal of a few hundred cubic feet

You mean a few million cubic feet. Do the math.

@Slow Down - You're saying that pumping on a single property doesn't draw groundwater from the surrounding area? That makes no sense. Look at the calculation included in my first post. If all of the water running @ 75 gal/min were just localized from one property, or only a few neighboring one's, all the home would be floating on a lake!

108,000 gal/day (75 gal/min x 60 x 24) is the equivalent of three swimming pools 20' x 40' x 5'. A month's worth of pumping is the same as draining 90 of those swimming pools - that's a lot more than a soil moisture in the ground where someone wants a basement.

Less than a century ago, most countries treated the planet's oceans as if they were a bottomless cesspool and an endless source of fish. Too many countries still treat the atmosphere in a similar way. Groundwater isn't an endless resource either, and pumping millions of gallons to enable one house to have a basement is ludicrous, and perpetuates a view that the water is free and there are no consequences for wasting it.

I'm for individual freedom, but wasting shared resources is not freedom - it's neglect, irresponsibility and theft.

When water is removed from clay soils, it causes desiccation.
Please read this web link about how drought has caused cracks in homeowners foundations and basements.

Web Link

If you have ever built with clay or mud you know that as it dries it is prone to cracking. The moisture in our clay soils support our homes, sidewalks, and streets.
Pumping out groundwater at this shallow level can also cause localized subsidence.
I have seen it in our home, and I have spoken with many people here over the years here who have seen and felt a difference in their homes after a nearby property has pumped out groundwater.

Clay soils are known to be prone to desiccation, consolidation settlement, and compaction. Consolidation is a process by which soils decrease in volume.

Most civil engineering books were written for large commercial projects on larger parcels of land; not small residential lots.

There is an old mansion in our neighborhood that was sold in 1996. The then-new owners added a large wing and expanded the basement greatly. At a block party that year, they explained that they wanted additional living space in the now 2-story deep basement that they would not have to pay property tax on. They put two bedrooms, a large jack-and-Jill bathroom, and a game room/media center down there. At that time, the bill for all of this was exceeding one million dollars and required a huge refinancing of their new mortgage.

Then came the sixty days of non-stop rain in January and February of 1998. The new owners had dewatered the basement for several months in 1997, but still the basement flooded. And flooded. And flooded. They used several pumps and we're still pumping out water in July of 1998. Due to the fact that floods are an "act of God", their homeowner's i surance covered NONE of the necessary repairs and replacements. They hadn't bought flood I surance because the lenders told them it was unnecessary, since the house was not in a flood zone.

As in a previous post, they ended up closing off this huge basement because the smell of mud and mold could not be gotten rid of.


I suppose that the moral is: if you insist on having a deep basement, buy flood insurance, regardless.

Just because the City of Palo Alto has been allowing groundwater pumping in their Green building code does not mean there are no impacts (both immediate and long term) to our community.

Write to individual council members, come in and speak (3 minutes) to the City Council and City Manager to tell them how you feel.

We have a Green Building Code for new residential construction and I don't think there is anything "Green" about digging a deep hole and vacuuming out about 75,000 gallons of water a day to put in tons of concrete, and then replant the property with drought resistant plants. A home which has withdrawn 13 - 18 million gallons of groundwater during severe drought can never be green. Think about it.

Again, please write to a city council member or come in on Monday night.

" At a block party that year, they explained that they wanted additional living space in the now 2-story deep basement that they would not have to pay property tax on."

This is bogus. If they said that, your neighbors most assuredly had a huge surprise once they finished the project and the new property tax bill showed up in their mailbox.

Property taxes (not counting parcel taxes) are based upon two assessments - the value of the land and the value of the improvements. When a homeowner takes out a permit to build/expand/remodel, the cost of that project is declared in the permit...that additional cost is added onto the property improvements portion of the property tax bill. Above or below ground - improvements are taxed.

Perhaps you misunderstood their statement. As in most cities, Palo Alto has a formula that determines the maximum square footage, as well as the maximum footprint a dwelling may have - based upon lot size. Basements do not count towards that calculation...probably what your neighbors meant...

treepeople.org in LA is doing amazing work. We should do the same. Web Link

I have not seen any trucks/ vehicles from the city filling up with the water via the valve. So I guess the owner and the city did a good job making us think the water will be reused!

It breaks my heart seeing this precious resource going down the storm drain while our beautiful street trees struggle to live.

"Property taxes (not counting parcel taxes) are based upon two assessments - the value of the land and the value of the improvements. When a homeowner takes out a permit to build/expand/remodel, the cost of that project is declared in the permit...that additional cost is added onto the property improvements portion of the property tax bill. Above or below ground - improvements are taxed."

That is only partially true. The improvements value is not simply taken from the building permit. The county assessor does a reassessment to determine the value of the structure only.

The CBS camera guy and his van are on Webster street right now covering the dewatering story. And the reporter is currently driving to the different dewatering locations.

This should be illegal! I thought we had a Green Building Code in Palo Alto.
How can the city allow people to do this? This amount of fresh water going anywhere at this time is sickening.

I bet the homes around it crack from having their properties dry up. This water is coming from a large area around this construction site.

I bet that the trees and plants prefer clay filtered groundwater over our imported treated water.

This shallow aquifer belongs in the ground to provide moisture to our trees and support for our homes.

Put your tv on tonight at 6pm CBS for the dewatering story.

It seems the builder Drew Marin is defending the dewatering on Webster street.

Just saw the piece on CBS. The city spokesperson defended the dewatering by saying the water just goes down to the bay - so it is not a waste of water.

So i guess when we water our landscaping it just goes down to the aquifer, gets pumped out by our dewatering neighbors, and down to the bay!

The shallow groundwater layers protect our our deeper groundwater (aquifers)
The shallower groundwater supports our foundations by providing moisture to our primarily clay soils, and of course it provides needed moisture to trees and landscaping.

Just because the city has allowed this does not mean there are no impacts to the environment.

We may need to use this shallow water in the event of an emergency, and also in the future.

This is misuse of water which belongs to all of us.

Take a look at the excavation sites which are vacuuming out our water.
Notice the clear demarcation line between the (intentionally) dried upper layers, and the naturally moist lower layers.

The city is saying pretty much that punping out water and let it go down the drain is business as usual. That was the old way when water was abundant. Why not set up an infrastructure to re-use the water for landscaping, street sweeping, spray over the landfill, etc? Or even set up a relief valve that neighbors can hook up a garden hose and use the water for non-potable purposes?

Here's the web link/video about the dewatering on Webster and other sites...run on CBS local news last night


Web Link

Quick. Let's hire more Sustainability Officers, consultants, pr people and community outreach folks to tell us to conserve, conserve etc. and that all this wasted water is really really ok.

No one who makes the rules in this city cares. No one in the city cares if the foundations of our homes and streets are damaged. No one in this city cares if trees die of drought stress. It's hard to prove years later, but you know it's true ... trees can't survive without water. People in our city government think groundwater is a waste product that should be discharged to the bay. Rich new homeowners think as long as they get underground bunkers in their dream homes, it's okay to build them in land which was once marshy or has water close to the surface.

No one who manages this city has ever cared about this. After years of trying to stop this, residents now no longer care because they are planning to flee soon.

I care.
This appears to be a loop hole in our Green Building Code.

The video from the news makes me want to cry. This city is OUT_OF_CONTROL.
I haul a bucket of water to help my plants. The trees just have to reach down to wherever to see it they will survive.

Given the direction from the governor of California the city Public Works does have the legal authority to force the construction crews to put the water in tanker trucks so that it can be dispersed throughout our park system. Our parks and trees need to be watered.

The Governor trumps city Pubic Works. If the city cannot get it's act together then there will be hell to pay in 2016 elections.

Goodness ... this is really a total non-issue.

Except for the fact that when they do all this sump-pumping they send vibrations out into the ground and you can hear it and feel it 24 hours a day for however long they do it for. I was not sure where it was, but I had one going for over a year in my area.

It is a dishonest argument to compare pumping dirty water out of a hole in the ground to fresh treated drinking water.

If we want to have appropriate parking ... wish that is what they were doing actually ... then people are going to need a way to make their houses bigger ... but in a basement or underground garage. Everyone complains about them going up in levels.

We have to make sensible decisions and choose our priorities, not go off on every fearful story someone wants to tell.

If the water level was falling around here they would not need to do the pumping would they?

This is an environmental issue, below the ground.

I was born and raised in Palo Alto. For all of the progressive titles this city likes to identify by I am beyond disappointed that such a "green" city would allow for insensible water loss. The issue is obvious. How is pumping water in a time of drought by any means acceptable/benign? NO EXCUSES.

I live next to a new construction site that has been pumping for a month. The root systems of these redwoods, hundreds of years old- bordering the property...it is the long term impact that concerns me. Is this worth the luxury of a basement? No. Matters/disruptions below the soil are serious - take it seriously, just as we do fracking. End this hypocrisy. A peak 50 gallons a minute being diverted - referencing KTVU.

The next question is, can we collectively change this? If we are getting subpar solutions, who do we report to next beyond the city?

Sensational or fearful? Concerned. We should be concerned. When has disrupting the earth ever been benign, besides an immediate-human created situation? Environmental studies 101.

@Disappointed, born and raised -

Roots of the redwood trees are shallow so they are not being harmed by dewatering. Our current drought and lack of irrigation is doing any damage you may see.

"You would think that a 350-foot-tall tree would need deep roots, but that's not the case at all with the Sequoia sempervirens. Redwood tree roots are very shallow, often only five or six feet deep."

And yes, Environmental Studies 101(I took that class too). Contrary to popular belief the groundwater being pumped is not wasted. It is still flowing towards the bay (where it was headed anyway) and helps maintain the marshlands that is habitat to many species, including the California Clapper Rail which is an endangered species. And to bring up fracking in this discussion? Fracking is at depths of thousands of feet and at extremely high pressures. Here we are talking about less than 50 feet deep and a pump you or I could buy at a supply store. Once the basement is finished and the pump is shut down the water table will return to normal levels in a short time.

We can write to our state assemblyman, Write to the governor, and contact AP News and larger news bureaus.

It is time for this practice to end before it spreads.
The city has downplayed this situation and tried to mitigate it, because it does not have the power to say "No" in the residential "Green Building Code" until council votes on it to disallow it.

We have a green building code, and this loophole has been open since it's inception.

If the city can't/won't change this to protect our properties and resources, we must move to city which would disallow it to happen in their residential neighborhoods. We need to move to a place where are property assets are protected.

The city does a good job protecting and regulating everything else, but not our shallow groundwater.

Good points Mizu.

But this thread has covered old ground twice now. Many fears have been raised, and answered with logical, reasoned responses, except one: why does water cause irrational fear and rage?

"Insert name here" has more-or-less ignored all the answers to his questioning and still insists construction must stop. And he is not alone. Why are logical, reasoned answers impotent in the face of water rage ?

Will we all write the governor and regulate our neighbors to death over non issues?

Where does water rage come from?

I'm generally leery of green fear mongering.

But I am having a hard time understanding two points in this argument.

First - "it goes to the bay so it doesn't matter."

All water goes somewhere, mostly to be evaporated and rained again. So? Therefore we shouldn't worry about using water? The point is what the water use or movement does, not where it "ends up."

Second, "this is deeper than the water you care about in the ground, so it doesn't matter."

Doesn't moisture levels under soil impact that soil? Such as dry soil under moist soil drawing the moisture down?

Also, moisture heavily impacts the density of earth; does this not change the volume of this earth as well? Does the density change of this deep earth not matter?

The impact of all dewatering projects in Palo Alto will lower the groundwater about 1/4 inch or less.

It's not going to affect soil moisture.

A worker at the dewatering site at 2133 Webster was taken away in an ambulance yesterday. The fire fighters/EMTs had to go down into the steep slope of the "basement" and carry the worker out. Bless our First Responders.

And please say a prayer for the injured man. These men work in dangerous conditions to support their families. They climb up and down makeshift steps into a very deep "basement".

I'm confused as to why there are no regulations against allowing this to happen! You would think people would know that the drought conditions have worsened in the Western part of the US over the last 10 years.

I learned that shallow groundwater works like a protective barrier to deeper aquifers. The soil has a certain holding capacity, and the moisture works it's way downwards over time due to gravity.

I thought that our city, like many other cities, was urging people and businesses to install permeable driveways and landscape so that rain water could percolate into the ground instead of flowing to the storm drain. Now they permit that same water to be pumped down the drain! Go figure.

And I thought that people were taught never to pour chemicals into the earth so as not to poison the land and water for others.

I also learned that our clay soils have a holding capacity which provides strength, dependent on the level of moisture. When it dries, it cracks! Doesn't it?

SB - As Aquifers said, "this thread has covered old ground twice now," but let's address your concerns.

"You would think people would know that the drought conditions have worsened in the Western part of the US over the last 10 years."

Agreed. Certainly in California in the past couple of years.

"I learned that shallow groundwater works like a protective barrier to deeper aquifers. The soil has a certain holding capacity, and the moisture works it's way downwards over time due to gravity."

OK, and the shallow aquifer is still there doing fine. And, yes, water obeys the laws of physics. Water tends to go downhill.

"I thought that our city, like many other cities, was urging people and businesses to install permeable driveways and landscape so that rain water could percolate into the ground instead of flowing to the storm drain."

I'm not sure about his one as far as the city goes, but it's usually good for water to go enter the ground. Agreed.

"And I thought that people were taught never to pour chemicals into the earth so as not to poison the land and water for others."

100% agreement here. Dead solid perfect.

"I also learned that our clay soils have a holding capacity which provides strength, dependent on the level of moisture. When it dries, it cracks! Doesn't it?"

OK, and when the project is done and the pumps are turned off and the water table rapidly returns to its historic levels, what happens? Surprise, the soil gets wet again.

So, as CrescentParkAnon stated "Goodness ... this is really a total non-issue." All that's really left was articulated quite well by Aquifers when he/she stated "why does water cause irrational fear and rage?"

"Why does water cause irrational fear and rage"?

Ask the farmers with aquifers that are now dry, that are pumping deeper In order to get water, that fields are being left fallow.

Ask the immigrants that no longer have work in the fields to support their families.

Ask the many residents that are taking quick showers, putting buckets in the shower, flushing toilets only when necessary, letting landscaping go dry, watching every drop that is used.

Ask any child if it's okay to have our precious water being pumped down the storm drains.

Ask the 1% that waste a resource that belongs to all of us in order to build a monster house with a basement.

Ask our neighbors that are running water hoses from 2133 Webster to capture the water that is being pumped.

Then ask yourself if this a justified rage or an "irrational" one...

Mini wrote the aquifers are fine and all will return to normal when pumping is done. Where is the evidence for this or are we supposed take the claim on faith?

If this were true under all circumstances then why worry about the lack of rain? The argument that pumping 50 gallons a day from multiple sites for months has little or no impact requires data to contradict the intuition that it does indeed matter.

“Ask the farmers …
Ask the immigrants …
Ask the many residents …”


Okay - sure. We are short of potable drinking water and irrigation for farms. It’s not like this is a new fact. However, if you shut off the dewatering, does that help the farmer?


No. It doesn’t. The problem is not water, the problems are costs. Costs of distribution, purification, maintaining reliable drinking water infrastructure. Water is just 100 yards off the shore of Palo Alto - you can desalinate all the ocean water the state needs if you have the funds. Costs are what separate your drinking water from irrigation water, and what separate irrigation water from sea water.

Rage against the machine all you want, but unless someone is willing to pay for the costs of managing water, that water itself has very little value. Local groundwater in particular has a very very low opportunity cost. Let’s say we shut off the dewatering. Then what happens?

Nothing. That water flows to the bay, and goes unused. You haven’t achieved anything.
So stopping the construction doesn’t help your farmer or immigrant or anyone saving water.


“Ask any child if it's okay to have our precious water being pumped down the storm drains.”

Okay ‘child’ (with ideologically framed question): is it okay to pump water through path A to the bay, or path B to the bay? Think carefully, because both end up at the bay. Let’s draw a diagram: see - they both go to the bay. Does it really matter?

No. That is the problem with groundwater - it’s opportunity costs are low because it is not harvested, not going anywhere else, except the bay.

“Ask the 1% that waste a resource that belongs to all of us in order to build a monster house with a basement.”

Good question. It shows your real issues are with the 1%, not with rational economics of water.


“Then ask yourself if this a justified rage or an "irrational" one…”

Irrational. Until you propose a cost effective means to opportunistically use this water, it’s value is low. Raging about it all you want still makes no difference. You can boil the ocean for fresh water, and it still comes down to this: costs. Including opportunity costs.

"I thought that our city, like many other cities, was urging people and businesses to install permeable driveways and landscape so that rain water could percolate into the ground instead of flowing to the storm drain."


There are two reasons for this - I don't think either have to do with groundwater.

First, our storm drain system has historically been overloaded in large storms. Any water that can be percolated locally into soils is less water we have to deal with in a storm. Lessens the chance of flooding.

Second, trees really suffer when their surface is paved over. Giving trees access to permeable surfaces allows surface water and oxygen to get to the roots. For an example, I noticed that Town & Country has some large oaks in the parking lot by Trader Joes, and they have put down radiating brick patterns in the asphalt to allow rainwater to get to the roots. Trees get all their water from surface water; very little from groundwater (unless it is VERY VERY shallow groundwater ~1' - 7'). They need this surface water to survive.

SS -

"Mini wrote the aquifers are fine and all will return to normal when pumping is done. Where is the evidence for this or are we supposed take the claim on faith?"

I'll assume you were referring to me. The name is Mizu, which is the japanese word for water. There is no need to rely on faith when we have science and history.

Water obeys the laws of physics. The pumps create a temporary depression in the water table. When the pumps are turned off this depression is filled because of higher water levels on all sides. Water tends to go downhill. It's not a perfect analogy, but think of a water bed. Push a finger down onto the water bed and create a depression. This is what the pumps are doing. Now remove the finger (remove the pump). Water seeks level.

Palo Alto used to rely on well water for potable water prior to receiving Hetch Hetchy water from the SFPUC. The water table was lowered in Palo Alto during that time of well water use. Once Palo Alto started receiving Hetch Hetchy water, the demand on groundwater caused by wells was reduced significantly. Soon after the water table recovered to its normal levels. I imagine the USGS has information on this if you desire to do further research.

OK, I get the fact that this pumping is/might be of little to no significance. But, the defense is that the aquifer is replenished from water uphill, correct? That's assuming that there is water that is being replenished uphill, correct? If you go to an extreme situation where it doesn't rain for the next year, there won't be as much water to flow downhill, correct?

As Mizu says, when PA used well water, the water table lowered. It lowered because there was water being sucked out of the ground. It was replaced when PA switched to Hetch Hetchy water.

If this drought continues for 3, 5 or 10 years, will pumping still not be a problem?

Even if the pumping isn't a problem, it is, at a minimum a PR issue. Makes it hard to tell people to not use water when they see how much is available to pump out of the ground, no matter where it ends up.

USGS estimates put the groundwater inflow at 3000AF/yr

My estimates of ALL dewatering projects in town is at most, in wildly exaggerated cases no more than 180AF/yr

Much more water is going in than going out through dewatering. So the groundwater is not really affected - maybe 1/4". ( inch) for a full year for all dewatering projects.

Even the most severe drought would still see inflow far in excess of dewatering.

The PR problem comes from irrational fears. Very real, I agree. But why? Can't people who care pick up a usgs report and read it? Or educate yourself on groundwater and estimate the relative scale of this non-issue?

We have real water problems to worry about, and complex problems to solve. Focusing on the wrong priorities is a real distraction, and potentially a political mistake. And water mistakes are costly.

Mizu - Apologies for the typo; the font appeared so tiny on my phone that I didn't realize the error.

You offer no evidence that dewater pumping doesn't negatively impact surrounding trees or cause subsidence of adjacent properties. We're also expected to take on faith that the removed water will be replenished and ground water levels will be restored to previous levels. That makes sense with normal rainfall, but we haven't seen that for 4 years; the water has to come from somewhere.

I understand that groundwater eventually makes its way downhill to the Bay. But while in the ground it does provide benefits such as preventing subsidence and replenishing the down stream water that has made its way to the Bay. Without data that clearly shows that the water removed by dewatering pumping is a tiny fraction of all the groundwater flowing to the Bay in the same vicinity, any claim that the pumping doesn't matter is mere conjecture.
I rely on facts and reliable data from which solid conclusions can be drawn, not hand-waving arguments that may sound plausible to some. I think we got the same type of response earlier in this thread, that pumping the water down the drain is inconsequential with no evidence to back it up. In the absence of evidence, it's prudent to assume that dewatering might have an impact.

I also think the premise behind allowing dewatering so that (mostly) new buyers can erect maximum lot coverage houses to extract the maximum value for the staggering price they've already paid for their property is misguided. Taking this to the extreme, Palo Alto would become a city of 2-story 4000-5000 sq ft homes with minimal yards but extravagant basements. The result will be property values even higher than what we currently see, and city that only the very wealthy can afford to live in.

Is that what we want for Palo Alto? As a community, I think we have a choice and curtailing the construction of basements on land where below ground construction is at least partially 'under water' is a reasonable course of action. Basements are a relatively new phenomenon in PA, in my experience, and the recent increase is the result of a positive feedback loop on property values. New buyer pays a high price for an existing property, then demolishes the old house and builds the biggest replacement structure possible to leverage the property value higher. I'd prefer that people motivated that way buy their homes in Atherton, Portola Valley or Los Altos Hills, rather than turn Palo Alto into maxed-out 6000 sq ft lots with few or no trees.

SS - I offered no evidence that dewatering doesn't negatively impact surrounding trees or cause subsidence of adjacent properties because it has already been covered in this thread and the other groundwater thread. I addressed the topics that you mentioned and offered the USGS as a potential source for more information if you desire to do the research.
You state "I rely on facts and reliable data from which solid conclusions can be drawn, not hand-waving arguments that may sound plausible to some." Same here. Prove me wrong. If you show me reliable facts and data that dewatering does harm and I will readily admit I am wrong. I have no problem with that. In the absence of such evidence I prefer to rely on science and historical data. As for the rest of your post, please read Aquifers post directly above yours.
So now the subject gets changed to quality of life issues in Palo Alto. May I suggest you start another discussion with that as a topic? This discussion has largely been about the water some individuals perceived to be "wasted" by dewatering.

Aquifers - A link to the USGS report and your calculations of the volume of water pumped by dewatering activities would be greatly appreciated. This is an opportunity to inform many skeptics on this thread. My quick search hasn't turned up the undated Santa Clara subsidence report (which I have seen before) and 2 reports that are 18-30 years old.

A few sources

Web Link


This one is quite useful

Web Link

As for dewater flows I took as given the quote on another post as 50gal/ minute from a dewatering critic.(although when I looked at a few sites I don't believe it is that high everywhere)

Assuming basement construction lasts 6 months

Assuming there are five active sites requiring active dewatering.

You get 180AF/yr.

Here are the addresses of four active dewatering sites:

2133 Webster
713 Northampton
2230 Louis
804 Moreno

Thanks, Aquifers. I found the 2004 EIP report commissioned by the City.
There's a 5th house on Harker that has been pumping for at least 2 months, probably a bit longer. When I first encountered it at the end of April, a resident filled a 5 gal bucket at the pipe outflow to the storm drain in 5-6 sec, so 50 gal/min is a good estimate.

Ground water pumping started recently from the lot at the corner of Parkinson and Newell, across from the Rinconada branch of the library.