Well Water 101
On 4 Oct 2025 by MikeTo unpathed waters, to undreamed shores.
— Camilo, Twelfth Night IV, 4. Shakespeare
Before taking up the ranch life, I lived in a world in which I turned a faucet, water came out and I didn’t give the rest much thought. (Well, except for earthquake risk but more on that in a moment.) Now on the Scahill Ranch, as with just about anywhere with acreage, our water comes from a deep hole in the ground on our property. It’s been a learning experience and so, with the expert help of our friend Ron Drew from Drew & Heffner Wells, here I’ll share those learnings with any fellow city slickers considering ranch life.
Drinkable Water Comes from a Hole in the Ground
As so often, xkcd summed it up better than I could have:
Just about anywhere on Earth, if you dig a hole, you’ll find water within a few thousand feet of the surface (usually much closer). Water in these layers, called aquifers (Latin for “water bearers”), pools in porous rocks, sand and soil in a complex equilibrium. Below, the pressure from overlying rock collapses pores into a dense, solid slab. Above, soil is so porous that gravity pulls rainwater right through. Thus, many local factors vary the depth, number & quality of aquifers, but they’re everywhere. In the US, far more water is in aquifers than in all the surface rivers & lakes combined. Seeping through all that rock is nature’s giant Brita charcoal filter, and so miraculous as it may seem, xkcd is spot on. Dig a deep hole, drink what comes out and it refills like magic. (Mostly…more on this in a moment, too.)
Perks & Precautions
The obvious perk is if you want to live in a place like the Scahill Ranch, which we sure think is awesome, you’ll almost inevitably join the 13M American homes with a private well. We are far from any municipal water supply (even housing developments in our areas are, I believe, on large well systems), so it’s embrace the well or live in the city.
The other great perk is the robustness of the system. When we lived in the Bay, a close friend was an engineer with the local water utility, neither of which will be named. She admitted that in the event of a substantial earthquake, we’d be without water for days, maybe weeks. With a well in the backyard, so long as the house is standing, we should have water. (The catch is electricity. This is a big reason we invested in solar batteries and a generator – topic of an upcoming post here.)
The downside is the standard when you go from customer to owner – everything is your problem. Hence the rest of this post I hope helps you understand your well and solve common problems. If a city slicker like me can figure it out, anyone can.
Before we get there, it’s worth clarifying the big owner risk everyone worries out – will we run out of water?
Water Flows…For Better or Worse
To a city slicker, at first a private well seems like a long straw of water just for your house. It’s scary to contemplate the long summer months with zero rain. But that’s not quite how it works. It’s more like a straw stuck in a giant subterranean lake (the aquifer) under our house but also under all our neighbors and the farms miles away. Certainly the almond orchards that surround us, beautiful as they are, use far more water than our 4 human, 2 dog, 11 chicken homestead ever could. Thus, the amount of water accessible is a complex function of runoff from nearby rivers, snowcap in the Sierras majestically overlooking our house and the water consumption of everyone for miles around. Water seeps slowly through aquifers (highly variable but a few feet a day is typical). Thus, we could dry our well if, say, a broken pipe triggered our pump to run non-stop. That would be bad, but over the coming days, water would seep back in to refill the well.
In the big picture, then, this is a classic tragedy of the commons problem. Just like overfishing ocean tuna, no individual on the aquifer is responsible for its conservation. (Except the electricity cost of running a 240V pump, which is not trivial.) There is much political debate on addressing the economics of water rights in CA and other states. All that’s beyond the scope of this humble post, but it’s a very real societal concern in part because in the short term, all our houses will be fine.
Well 101
Fundamentally, the well itself is just a deep hole in the ground. Ours is about 500 ft because local experts like Ron know our local aquifers are a little under that. After reinforcing the walls of the hole with concrete, they “airdrop” a suitably long pipe with slits in the sides down the hole. (Ron said “airdrop”, and while I’ve never seen a 500 ft pipe dropped from a helicopter into a well, that sounds awesome. Ron, if you’re reading this, please send a video of a helicopter.) Thus, water from any aquifers above drops into the bottom of the pipe where, not coincidentally, is your submersible pump – an electric motor in a waterproof cylinder topped by a series of fan blades. Heavy 240V wires run from the control box at the top of the well down to the pump where spinning the blades generates enough pressure to drive water all the way to the top of the well and voila! Everything from here is accessory & control.
The main problems the accessory & control components solve are 2:
- The submersible pump runs at its one optimal speed. But water consumption in our house is highly variable. Indeed, between peaks for showers and my elaborate garden drip irrigation, our modal minute water use is 0. To boot, we want our water pressure to be roughly constant. How the heck can you accomplish such a thing from a single speed pump?
- Buried 500 ft underground, the submersible pump is a huge pain to service or replace. How do you minimize its wear to maximize its life?
The answer to both is to use a capacitor or, in our case, multiple capacitors.
The basic setup is a bladder tank with a pressure switch. The well pump pressurizes the tank, and that pressure feeds the house. When the switch mechanically detects pressure below 30 PSI, it closes and so sends power to the well pump until it hits 50 PSI. E voila! Steady pressure to the house with less wear on the pump. So good indeed many of our neighbors get by on just this.
We’re fortunate to have 2 more parts that do the same thing but better – a 2600 gal holding tank and a booster pump. Our well pump connects to that huge tank instead of the modest bladder. Two floating valves inside the tank turn on our well pump when the tank gets low, then off when full. Filling a 2600 gal tank instead of a 30 gal bladder means the pump runs longer but much less frequently. On / off cycles are really what wear the pump (just like an air conditioner), so this is a good thing. The bladder switch measuring house pressure, thus, is triggering the booster pump to draw water from the tank. Fixing or replacing the booster pump, 3 inches above the ground, would be way easier than fixing the well pump, 500 feet under it.
Troubleshooting
While our well would be highly resistant to the zombie apocalypse, smaller things need attention.
Obviously #1 is electricity. I figured the giant holding tank could be tapped manually in a pinch like a water heater. Turns out that’s not true (at least not at our house). Losing power would relegate us to the 19th century with no lights, no internet and no water. All the more reason we invested in solar, batteries and a generator.
#2, surprisingly, is ants. The bladder switch gets warm, and this draws ants and similar critters. Unluckily for all involved, if they crawl into the metal contacts, they can get zapped and stuck there. A big enough ant will prevent the contacts from closing when the pressure drops, and you’ll suddenly lose water once the pressure in your pipes runs out. Annoying but an easy fix. Some just kick the switch to knock the bug loose. I prefer to open it and, carefully with a nonconductive tool, flick the contacts. If the contacts need more cleaning than that, definitely cut the breaker first as a 240V jolt is no joke. Ron recommends applying dilute vinegar periodically in the summer to keep the ants away.
#3 weatherproofing. Historically here, winter nights have gotten cold enough to freeze pipes. Thus, as fall cools off, you’ll want to buy flexible foam wraps for exposed pipes (mostly above ground hose bibs). Ditto styrofoam hats for the hose bibs themselves. Probably wouldn’t be enough for my friend Z in Alaska, but here it keeps the pipes from freezing and so from cracking the pipe. Once it thaws, you’d have a massive hemorrhage. The circuitry above will detect the pressure drop and dutifully pump water until you shut it off manually or your well runs dry. (As above, this won’t drain the entire regional aquifer, but it will be a major bummer until water gradually seeps back from surrounding rock into your well.)
#4 fancier tools. As the broken pipe catastrophe illustrates, the basic pump hardware is vulnerable to a major leak going undetected – perhaps it’s way off in a corner of your ranch or you’re on vacation. Fortunately, you can install a “pump saver” to shut down the well pump if it runs dry or there’s an electrical fault. It won’t stop all the water in your tank / well from flooding your ranch, but you won’t also have to shell out mucho dinero to replace the well pump at the same time. At a commercial scale, Pumpsight from our good friend Morgan is the way to go as not just catastrophic pump risk but even the simple efficiency of irrigation is a big deal when you’re managing hundreds of acres of orchards scattered around the Valley.
However, Ron’s #1 tip – and despite his conflict of interest I definitely agree – is to get a well inspection. They’ll check your water level and hardware. The seller should pay for this essential due diligence before you buy a ranch in our neighborhood, which I sure hope you will now that you know getting water from a well is kinda cool!