The system
Four pieces make up a water system like this one: the well, the pump and the power that drives it, the storage that decouples supply from demand, and the buried line that carries water to where it is used. Leave any of them out and you own a project, not a water system.
| Location | Torrance County, New Mexico |
|---|---|
| Completed | July 2026 |
| Well | 200 ft, 6-inch steel casing — drilled by a licensed New Mexico well driller |
| Pump | RPS 800 helical-rotor solar pump |
| Pump power | Dedicated 1,200 W array with MPPT boost controller |
| Backup | Generator auto-switch |
| Storage | 2 × 2,500-gallon NSF-61 cisterns (5,000 gallons) |
| Water line | ~520 linear feet of 1.5-inch HDPE (NSF-61), minimum 30-inch depth |
| Inspection | Water line inspected by New Mexico CID |
| Contract value | About $55,000 |
| Payment terms | 70% deposit / 30% on completion |
Why the pump gets its own array
The RPS 800 runs off a dedicated 1,200 W array through an MPPT boost controller rather than sharing the property's household power. That separation is deliberate. A pump on its own array is not competing with the house for stored energy, and a boost controller lets a modest array keep the pump turning across a much wider range of light than a direct-wired panel string would — through morning, late afternoon, and passing clouds instead of only under full midday sun.
A helical-rotor pump suits the duty: modest volumes against high head, and tolerance for the variable input power any solar-direct pump sees all day. The system is not trying to deliver house pressure on demand — it is moving water steadily into storage whenever the sun is up.
The generator auto-switch covers the rest. Water is the one load on an off-grid property you cannot defer: a stretch of heavy weather, or a cistern that needs filling faster than daylight allows, and the pump needs a source that is not the sky. Automatic switchover means nobody has to be home to make that happen.
Five thousand gallons of buffer
Two 2,500-gallon NSF-61 cisterns give the property 5,000 gallons of stored water. Storage is what turns a slow, sun-dependent pump into a system that behaves like plumbing. The pump produces on the sun's schedule; the house consumes on the household's. The cisterns absorb the difference, and they carry the property through cloudy stretches and any day the pump is down for service.
The NSF-61 rating is worth asking any contractor about by name: it certifies the tank and the pipe as approved for contact with drinking water. Both the cisterns and the buried line here carry it.
The 520 feet nobody ever sees
Roughly 520 linear feet of 1.5-inch HDPE ran from the well and cisterns to the point of use, buried at a minimum of 30 inches. Depth is freeze protection first and mechanical protection second; a shallow line in New Mexico is a line you will dig up again.
HDPE earns its place on runs this long: flexible, tolerant of ground movement, and far fewer joints than rigid pipe — and every joint you do not install is a leak you will never chase across 500 feet of desert.
The water line was inspected under New Mexico CID jurisdiction, with the permitting and inspection sequence handled through Torrance County. Counties vary in how they run that process, which is why we scope inspection time into the schedule rather than treating it as a formality at the end.
What a well actually costs
The well was drilled to 200 feet with 6-inch steel casing by a licensed New Mexico well-drilling contractor. We manage the schedule, coordinate the driller against the rest of the scope, and carry the pump, storage, power, and distribution — but the borehole is drilled by a licensed driller. We do not hold a drilling license and do not claim one.
Depth is the one number nobody can promise in advance. You are drilling until you find water, and the ground decides where that is. This contract was priced to 200 feet, with drilling beyond that billed at $75 per additional foot. We would rather write it that way than quote a flat number padded with contingency the owner pays for whether or not the hole needs it.
The payment structure follows the same logic. Terms were 70% deposit and 30% on completion, because a water system is front-loaded with material — casing, pump, cisterns, pipe, and the array all get bought and the driller mobilized before there is anything to look at on the property.
What we would do differently
Two takeaways from this build, both about the ground rather than the equipment.
- Walk and probe the whole trench route before pricing it. When trenching is billed by the day and the terrain is rocky, the route itself is a cost driver worth investigating along its full length — not just at the endpoints. More upfront information about what is under a 500-foot run means a tighter estimate and fewer surprises for the owner mid-job.
- Have the site ready before the driller mobilizes. Cistern pads, material staging, and access for heavy equipment are all cheaper to sort out ahead of time than to work around once a rig is on site. The more of the property that is prepared before drilling day, the fewer mobilizations the job needs.
Both reduce to one principle: on a water job the expensive uncertainty is underground, so spend the cheap effort up front learning about it.