Creating the Horizon Pool

A Contractor’s Guide to Perfecting the Infinity Edge Pool

The infinity edge pool—also known as a zero-edge, vanishing edge, or negative edge pool—is the ultimate statement in luxury aquatic design. It creates an illusion that the water merges seamlessly with the surrounding landscape, whether that's the ocean, a desert horizon, or a cityscape.

However, designing and constructing a perfect infinity edge is one of the most technically challenging projects in aquatic contracting. It requires surgical precision and specialized engineering.

1. The Essential Engineering: The Catch Basin (Surge Tank)

The defining feature of a vanishing edge is that the water flows over one or more sides. This overflow must be collected, and this is where the catch basin comes in.

Function: The catch basin (or surge tank) is a secondary underground holding tank positioned immediately below the vanishing edge. It collects the overflowing water and holds the necessary volume to cover the weir wall perfectly.
Volume Calculation: The basin must be correctly sized to accommodate the water displaced by swimmers (the "surge") and the volume of water required to fill the entire gutter and weir system. Miscalculation here leads to either overflowing the basin or breaking the vanishing illusion.
Integration: The water is collected in the basin and then pumped back up to the main pool body for re-filtration. This loop is critical to maintaining the visual effect and water chemistry.

2. Achieving the Perfect Level (The Weir Wall)

The visual magic of the infinity edge hinges entirely on the top of the weir wall being perfectly level.

Precision: The weir wall must be engineered to a tolerance of no more than 1/8 of an inch (3 mm) difference across its entire length. Any greater deviation will cause the water to sheet unevenly, ruining the smooth, reflective look.
Construction: This typically requires meticulous leveling of the Gunite shell, followed by a final, precise coping or tile application along the wall's top edge.

3. Waterproofing and Plumbing

Infinity pools have more surface area exposed to movement and different pressures (between the pool body and the surge tank), making waterproofing paramount.

Dual Waterproofing: Both the main pool and the surge tank require robust, high-quality waterproofing membrane applications to prevent leakage into the surrounding soil.
Specialized Plumbing: The plumbing system is more complex, requiring pumps to move water out of the pool (over the edge) and separate pumps to move it back from the catch basin through the filtration system.

Conclusion: Trusting the Experts

An infinity edge pool is an investment in architectural drama. Given the zero-tolerance requirements for leveling, the complex hydraulics, and the critical waterproofing needs, it is vital to entrust this project only to contractors with specialized experience in these systems. When executed flawlessly, the result is breathtaking.

Ready to elevate your property with a signature aquatic feature? Contact us to discuss the engineering perfection of your infinity edge design.