One of our most frequently asked questions is “what’s best pump to deal with cellars/basements that periodically get flooded out?” Typically, the flooding occurs after heavy rainfall, if the water table is high or if you live in close proximity to a river/lake. The solution is a submersible pump.
For this type of application, we would normally recommend a submersible pump – a small electric pump, which can be completely (or partially) submerged underwater. The pump sucks the water through a strainer in its base and pumps it from the outlet (normally located on the top of the pump) through a hose to a suitable discharge point (the nearest drain or similar).
For ease of use, most submersible pumps are available with a float switch (it’s the round, black and orange part of the pump in the photo) – this a similar to a ballcock in a toilet cistern – when water is present it floats up and turns the pump on, when the water has drained away the float drops down and turns the pump off. This allows for automatic operation, meaning the user doesn’t have to manually turn the pump on and off when the water rises. However, submersible pumps with float switches work best when installed in a sump (essentially a hole dug in the floor) and need to be of a suitable size to allow the float switch to move freely (typically around 400 mm x 400 mm x 400 mm). They will usually only drain water down to a level of a few inches.
If you prefer not to dig a sump, we can offer an alternative – a puddle pump. These low-level drainage pumps are engineered to pump water from flat surfaces down to around 1 mm deep (hence the name!), and are ideal for cellars, basements, car parks and flat roofs.
Due to their low-level performance, puddle pumps are not supplied with a float switch and as such are normally manually operated.
For fixed installations, such as keeping your cellar/basement dry, we would recommend using an automatic control panel which uses a sensor to detect the presence of water and operate the pump.
For other applications, such as drainage of persistent nuisance water from areas such as flat roofs and car-parks puddle pumps are best manually operated and can be used like a vacuum cleaner to “hoover” up the water – you can even sweep the water into the pump to help it drain away!
Our Submersible Pump Recommendation
Our most popular submersible pump for domestic drainage is the Pedrollo TOP range, these lightweight yet robust pumps are available in a number of different sizes, each offering improved performance (the bigger the electric motor, the faster is will drain the water away).
Pedrollo also offer a puddle pump, the TOP Floor which drains down to 2-3mm, but our most popular model is the JS-Pumps RSD-400. This stainless steel-bodied pump provides excellent performance and superior low-level drainage.