Decision Set · Rev I · Clearing measured
Lap Pool
Winchester, TX
Two things will bite you, and neither is the pool. Bedrock sits 20–40 inches down, so you are digging into weathered shale — get it priced in the bid, not as a change order. And the tap water is soft, which will quietly strip calcium out of brand-new plaster unless you put it back on day one. Work the sheets in order.
The Gate
BwF Burlewash · bench siteSix conditions decide whether a pool is buildable here at a sane price, and none of them are about the pool. NRCS maps this ground as BwF, 20–45% slopes — but the pool would sit on an existing flat bench inside that polygon, so the wall problem mostly evaporates. What does not evaporate: bedrock at 20–40 inches, and a soil that sheds water instead of absorbing it. Confirm the bench with the survey data from the earlier construction on the property, then set the slider honestly.
The map unit describes a hillside, but the pool would sit on an existing bench cut into it — so read the slope number below as the bench, not the polygon. Two findings survive the correction intact, and they are the ones that cost money. Bedrock at 20–40 inches means you will be excavating into weathered shale — rippable, not blastable, but a real line item. Water table below 80 inches, no ponding, well drained — so the perched-water and floating-shell risk is off the table, which is a genuine win. But Ksat is 0.00–0.06 in/hr and the runoff class is very high: water does not soak into this ground, it runs across it. And the map unit is 20 to 45 percent slopes. And because the bench sits inside a 20–45% hillside, everything uphill of it drains onto it. The drainage problem got more important when the slope problem got smaller, not less.
| Bearing | Good news. The shell will bear on weathered bedrock, not on expansive clay. Once you are in the rock, the structure sits still. |
| Rock excavation | You need ~54″; rock starts at 20–40″. Price rock excavation in the bid, not as a change order. Paralithic = rippable with a large excavator or hammer. |
| Stormwater | Hydrologic Group D, runoff very high. A pool and deck is a large impervious pad on a hillside that already sheds water. You must intercept upslope sheet flow with a swale or French drain above the pool. |
| Erosion | Land capability 6e — severe erosion hazard. Disturbed soil on this slope will move. Silt fence, immediate stabilization, and a revegetation plan. |
| Wall drainage | The soil will not drain, so anything you backfill behind a wall must be drained by gravel and pipe. Undrained walls on impermeable soil fail. |
Running the long axis along the contour is the single cheapest decision on this sheet.
Manageable bench. Rotating this pool to the other orientation would change the wall cost by roughly $6K. That is not a detail — that is the decision. None of this is in the $135K–$215K on sheet A-2 — add it.
6 conditions still unknown. That is the next 30 days: geotech engineer, septic as-built, an electrician on site, and a tree survey. Call it $2–4K to retire the biggest risks on a $150K decision.
Configurations
Same site, same scale, three poolsThe scale bar settles it: the open ground measures roughly 50 × 35 ft, and the shed is about 36 ft on its long axis. A 50-ft lap pool needs a 60 × 20 ft pad, plus room for an excavator to swing and 100+ cubic yards of spoil to sit. It does not fit as the clearing stands. So Option D exists: 40 ft, still a real lane, and it drops in without felling a single pine. A and B are drawn as if the trees came down.
↔ Swipe the drawing to pan
The Shade Structure
Shade is not debris · different problemsTexas heat is a real argument for cover, and the wrong structure charges you twice — once to build it, once to reheat the pool it shaded in March. Toggle through and watch two numbers move in opposite directions. The structure draws itself onto the site view above.
Three or four tensioned HDPE sails on engineered posts, angled to shed water and wind. They block 90–95% of UV over what they cover, cost almost nothing next to the alternatives, and — the important part — they come down. De-rig them in October and the pool heats itself for free all shoulder season. This is the option that respects the tradeoff instead of pretending it does not exist.
- Take them down before severe storms. Fayette gets real thunderstorms, and a tensioned sail is a sail.
- Posts need engineered footings — but bedrock at 20–40″ means shallow piers straight onto rock. That is a rare gift from this site.
- Mesh fabric. Needles go straight through. This does nothing for debris.
- Cheap enough that you can try one, live with it a summer, and add more.
The trap, stated plainly. Shade and debris are different problems, and no single structure solves both. A shade sail is mesh — needles fall straight through it. A solid roof stops the needles by catching them itself, and then you clean a roof, and it drips. The thing that keeps needles out of the water is the automatic cover, which is already inside the build number on A-6. So: buy the shade for the people, and let the cover do the water. And price what shade costs you — solar gain is the biggest free heat source this pool has, and anything you put over it in March is money handed to the heat pump.
Weighted Decision Matrix
Move the weights · scores 1–5Defaults are deliberately neutral, and there is a new criterion: fits the clearing. A and B score 1 on it because they need mature pines felled — and every pine you fell to make room is shade you then pay to rebuild. Watch which weight has to move for the answer to flip.
| Criterion | Weight | A · Lap | B · Hybrid | C · Spa | D · Short |
|---|---|---|---|---|---|
Lap-swim quality True unbroken distance, no turns mid-set | 20 | ||||
Fits the clearing Without felling mature pines | 14 | ||||
Family & social use Grandkids, shallow lounging, gatherings | 12 | ||||
Build cost Capital out the door — lower is better | 18 | ||||
Annual operating cost Chemicals, power, heat | 10 | ||||
Maintenance burden Pine needles, year-round, on all of it | 12 | ||||
Schedule certainty Weather, soil, access, and tree work | 6 | ||||
Year-round usability Swimmable in January without a gas bill | 12 | ||||
Property value Appraisal lift vs. appraised tax cost | 10 | ||||
| Weighted score | 114 | 2.88 | 2.81 | 3.81 | 3.51 |
The Water
Lee County WSC · soft water is not freeSaltwater is chlorine — a cell splits salt to make it. So this was never a chemistry debate, it is a hardware bet, and the fill water places it. The well is sulfuric and out. The tap is Lee County WSC, whose deep wells draw the confined Carrizo-Wilcox — which is why it feels soft on your hands. That is good for a salt cell and bad for new plaster, and the fix costs about forty dollars if you know to do it.
Salt cell — and add calcium
Soft water is aggressive water. It will eat the plaster to satisfy itself.
This is the counterintuitive part, and it is the one that damages pools. Water this soft is calcium-hungry. Dropped into a brand-new plaster shell, it will dissolve calcium straight out of the surface to reach saturation — etching, pitting, and a chalky finish, permanently, in the first weeks. The fix is not exotic: you add the calcium back before the water can steal it.
- Dose calcium chloride at startup to bring calcium hardness to 200–400 ppm. This is the single most important number on this page. Non-negotiable on a new plaster shell.
- Manage the Langelier Saturation Index to between −0.3 and +0.3. Your builder should hand you a startup chemistry plan; if they shrug at the acronym, get a different builder.
- The good news: soft water means no scale plating a salt cell. Salt is genuinely the right call here — gentler water, far less hand-dosing, which matters more the older the owner gets.
- Deep Carrizo-Wilcox wells often run sodium-bicarbonate type — soft, but with high pH and high total alkalinity. If so, expect to be a regular acid buyer. Ask for alkalinity and pH, not just hardness.
What to ask Lee County WSC for. The CCR will not have most of this — hardness is unregulated, so it is not required on the report. Ask the office directly for: calcium hardness, total alkalinity, pH, TDS, and sodium. Five numbers. They decide the sanitizer, the startup chemistry, and whether your parents spend the next decade buying acid.
Ten-Year Number & Schedule
A-2 selection · shade from A-3 sits on topCost of ownership — A · True Lap
| Build (incl. deck, barrier, cover) | $160,000 |
| Chemicals · 10 yr | $9,000 |
| Power, VS pump · 10 yr | $5,000 |
| Heat pump operation · 10 yr | $11,000 |
| Service or DIY time · 10 yr | $18,000 |
| Needle load: cover cycles + skimmer · 10 yr | $7,000 |
| Resurface reserve (yr 12-15) | $14,000 |
| 10-year cost of ownership | $224,000 |
| Plus property tax on appraised improvement | ~1.7–2.0%/yr |
Directional midpoints for Central Texas, 2026. Not a bid. These are flat-site numbers. On this site, add the retaining wall and rock excavation from A-1 on top — they are the three lines most likely to blow past everything: slope, rock, and access.
Schedule — gunite path
Wet clay stops excavation and shotcrete cold. Build a month of weather float into any date your parents are told. Tree clearing has to happen before anything heavy can reach the pad — sequence it early.
Send It Back
No account, no databaseEverything you change on these sheets — gates, soil, pool choice, weights, scores, water — can be packed into a link. Put your name on it, copy the link, text it back. Whoever opens it sees exactly your version.
Planning estimates, not quotes. Verify soils, septic setbacks, service capacity, tree clearing, and the utility's water report before soliciting bids.