Building MASSIVE Swim Pond with Old Equipment ep. 3

Natural Swim Pond Backyard Build (Progress + Key Solutions)

• Dug and shaped the pond to exact measurements, creating an “earth pool” intended to blend into the landscape.
• Solved the groundwater-under-the-liner problem:
  • Installed a French drain that routes to a sump pump in a culvert beneath the area where the liner goes.
  • Goal: prevent water from sitting beneath the liner to avoid failure/settling issues.
• Hardened/strengthened the wet, clay-heavy base before liner installation:
  • Used Portland cement (plain cement, not concrete).
  • Raked cement into the wet/squishy areas to create a firmer “water bed” that would harden.
  • Added a little water to help the cement set properly.
  • Purpose: prevent settling that could rip the liner.

Earthworks, Slope Prep, and Compaction

• Built stable pond walls (with noted concerns):
  • Existing wall materials were at risk of crumbling as material was added.
  • Plan: rake the entire pool, remove sticks/rocks (using a wheelbarrow), and “give the hill a haircut” so debris wouldn’t undermine stability.
• Created a level base using limestone screenings:
  • Hauled in roughly 80,000 lb of dirt/sand-like material (described as a huge load).
  • Coated the pool with limestone screening to flatten and remove bumps.
• Wetted then compacted the limestone screenings:
  • Wetting helped compaction.
  • Used heavy equipment, including a large compactor/tamper/“whacker”, with a mention of a 12,000 lb compactor to reduce future shifting.

Geotextile / Liner-Underlayment Installation (Critical Protection Step)

• Measured and cut geotextile fabric based on roll length and pond dimensions.
• Noted geotextile comes in different “ounce” weights:
  • They selected 10 oz geotextile intended to go beneath the pond liner for improved puncture resistance and durability (compared to driveway use in the past).
• Installation method to avoid pulling debris into the pond:
  • Used long chains (with neighbor help) to thread/pull the fabric horizontally across the pond without dragging exterior rocks/soil underneath.
  • Overlapped seams by at least 4 inches across the pond.
• Seam finishing:
  • Smoothed wrinkles/creases by folding and gluing/melting seams, taking care not to burn through.

Liner Timing + Boulder Preparation

• Did not install the liner immediately after geotextile:
  • A liner this size typically needs many people; they estimated ~10 (expecting ~5)—so they waited.
• During the wait, they focused on rock hunting and hauling boulders from their 65-acre property to create the pond’s natural look while reducing liner-related issues.

Rock Selection, Hauling, and Design Guidance (Speaker / Contractor Insights)

• Collected massive boulders, with a note to avoid buying stone if the property already has enough.
• Visited a quarry / rock hunting area and consulted Derek (Quiet Nature).
• Boulder selection guidance included:
  • Choosing rocks with the right sizes/height/width for natural appearance.
  • Using some rocks as “bedrock” looking features.
  • Building a realistic cross-section that works with filter-box heights and allows cobble layering on top.
  • Example rock density math: roughly ~180 lb per cubic foot to estimate weight.
• Notes on function and aesthetics:
  • Rocks can provide natural seating/steps inside the water.
  • Variety matters: some single large stones, some double-stacked, and different sizes especially near the edges.

Liner Placement + Seam Melting (Major Milestone + Issue)

• Liner details:
  • Heavy-duty liner around 50 ft x 70 ft, folded up on pallets.
  • Confirmed direction arrows and planned to roll from one end to the other (70 ft), then unfold to the sides.
• Pre-liner final check:
  • Crawled/walked under/around to confirm no rocks were beneath the geotextile.
  • If a rock was found, they cut out and patched the geotextile.
  • Patched the fabric using a method involving cutting and heating/melding the seams.
• Liner installation and smoothing:
  • Placed the liner with an excavator.
  • Pulled rocks toward the edges to help remove wrinkles and distribute material smoothly.
  • Continued smoothing until shelves/sides looked close enough for final shaping.
• Seam melting over heat:
  • After placement, they had to melt/seal liner seams similarly to the geotextile seams.
  • Warning: the liner was very hot (“could cook an egg”), making seam work stressful because it was expensive.
• Problem encountered:
  • One seam required a patch during finishing.
  • They suspect the issue may be related to wet ground water, making it difficult to see/dry properly.
  • Planned to get pro help from Derek’s team, with Tiffany arriving the next day.
• Status:
  • Despite the seam issue, they still ended the week with a dramatically more complete pond—“the pond looks completely different… It’s done.”

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Notable Locations / Products / People Mentioned

Locations / Setting

• A backyard natural swim pond on a property with 65 acres
• Canada mentioned as a comparison

Equipment / Materials

• French drain, sump pump, culvert
• Portland cement (plain cement)
• Limestone screenings
• Geotextile (10 oz fabric) beneath liner
• Heavy-duty pond liner (50 x 70 ft)
• Excavator, dump truck
• 12,000 lb compactor
• Walk-behind tamper/“whacker”

People / Speakers

• Chris, Josh/Joshu(a), Crystal, PJ, Tony, Bella, Iszy, Tiffany, Derek (Quiet Nature)