It is easy to blame the pump when a flood system underperforms. Often, though, the pump is fine and the real problem can lie somewhere else in the installation. This case study is a good example: a sump pump that could not move water as effectively as it should, not because of the pump, but because of the hose.
The setup
This homeowner had a surface water sump chamber with a pump, sized to activate during flood conditions and discharge water away from a vulnerable area. The idea was sound. The problem only came to light later: the builder had originally fitted layflat hose as the discharge line, and inside the chamber it was kinking and choking the flow.
The problem
A sump chamber is only as good as its ability to get water out. The pump can only perform if the hose lets water leave the chamber freely, and here it could not. The photos show the original hose bending and folding inside the chamber, which cuts the effective flow rate and limits how much water the pump can actually move.
This is the classic drawback of using layflat hose in the wrong place. Layflat can be excellent in the right place, easy to store, quick to deploy, and ideal for temporary pumping, emergency flood response and moving water across flat ground. But because it flattens when not under pressure, if it is constrained, folded, sharply bent or routed through an awkward space, it can collapse or kink. A chamber is exactly that kind of awkward space. We have also discussed before how an elbow hose tail can be used on certain puddle pumps to reduce kinking, which you can read here: Using an EVAK Residox Puddle Pump Behind a Flood Barrier.
The pump arrangement
The chamber had a Tsurumi POMA installed, which suited it well thanks to its narrow tube float switch. In smaller chambers, float design really matters: a wide or tethered float can catch on the chamber walls, pipework or cables and stop the pump switching on and off correctly. The POMA's compact float avoids that.
The homeowner also had an APP HD-15, as a robust high-flow option for managing water on site.
The solution
We supplied a new green reinforced suction and delivery hose to replace the layflat. At 2 inch / 50mm it matched the pump's discharge, and because it holds its shape under both suction and pressure, it does not collapse or kink the way layflat had. It was fed through the existing conduit, giving a reliable discharge route and removing the restriction that had been throttling the flow.
The existing conduit is made this straightforward.
Why the conduit mattered
This case highlights a wider point about sump installations: it is not just the pump that matters, it is the route for the discharge hose and the route for the electrical cable. A conduit is important for the cable, giving it a protected, accessible path, and here the same principle paid off for the hose, because there was an accessible route, the homeowner could upgrade the discharge without excavating or redesigning the system.
It is the same theme we have covered in our blog on common sump pump mistakes which included a situation where the cable had been concreted in without a suitable conduit - which would make replacement very challenging.
Layflat hose is not a bad product, it is the right tool for temporary pumping, emergency response, construction sites and moving water across open ground.
The mistake is using it where it will kink, collapse or be hard to inspect. For a sump chamber or any more permanent discharge route, a reinforced suction and delivery hose or rigid pipework is usually the better choice. Browse all options in our water pump hoses range.
The outcome
The homeowner improved the performance of the sump arrangement without replacing the system. The upgraded 50mm reinforced hose removed the main restriction in the discharge route. It also allowed them to install their APP HD-15 pump, which had the optional 50mm outlet.
