TopTank 5000L Underground Spherical Water Tank

TopTank 5000L Spherical Tank

The TopTank 5000L Underground Tank serves as a high-capacity subterranean reservoir for potable water storage, rainwater harvesting, and borehole backup systems. This heavy-duty polyethylene vessel utilizes a spherical geometry to distribute external soil pressure evenly across the hull. It provides a reliable alternative to concrete cisterns in residential and commercial plumbing layouts.

Built for the Job

Plumbers and site supervisors select this spherical unit for sites with limited surface space or where aesthetic requirements demand hidden utilities. The rotationally molded construction eliminates seams, significantly reducing the risk of leaks or structural failure under hydrostatic load. Contractors must install this unit on a level, compacted sand bed to prevent point-loading. The design accommodates standard inlet and outlet piping sizes common in Kenyan construction. Its robust ribbing provides the necessary grip for backfill material, preventing the vessel from shifting or floating in areas with high water tables when properly anchored.

• Subsurface rainwater collection for large-scale landscaping and irrigation systems.

• Primary water storage for residential developments where ground-level space is restricted.

• Industrial gray water recycling reservoirs for facility management and maintenance.

Product Highlights

Structural Integrity

The spherical profile naturally resists crushing forces from surrounding earth and groundwater pressure without requiring internal bracing.

Material Specifications

• Manufactured from food-grade, high-density polyethylene for safe potable water storage.
• Corrosion-resistant material prevents degradation from acidic or alkaline soil conditions.

Technical Specifications

What’s Included

• 1 x 5000 Litre Spherical Underground Tank

• 1 x Heavy-duty lockable manhole cover

• Pre-molded inlet and outlet connection points

On-Site & Workshop Notes

• Always perform a pressure test on all pipe connections before final backfilling to avoid costly re-excavation.

• Use clean, washed sand for the base and initial 300mm of backfill to ensure uniform support around the sphere.

• Ensure the manhole remains accessible for periodic cleaning and inspection of the float valves or pump systems.

• Verify local building codes regarding setbacks from foundations and property lines for subsurface storage vessels.