7 Interesting facts about Submersible Pumps (Sump Pumps)

Sump pumps are usually installed for 3 reasons:

• the water table is equal or above the foundation of the structure
• the structure maybe built in an area which is prone to flooding
• You may have a cavity drain waterproofing system that relies on it.

If your basement has a history of flooding, you live somewhere that experiences large quantities of rain (or snow) or you wish to protect your property from future water damage, then sump pumps should be considered.

A sump pump or pump station is a system which has been designed to collect water ingress or hydrostatic pressure which naturally enters a below ground structure (basement) and safely diverts it. A sump pump is usually installed along with a Cavity Drain System or Type C Waterproofing solution. Sump pumps are usually hardwired into a home’s electrical system and installed inside the building/structure.  As with domestic appliances (hoovers, dishwashers, etc) a 240v single phase power is used.

This is a difficult question as there are various considerations which should be taken into account when designing a basement or waterproofing system for a below ground structure.

An understanding of BS8102:2009 is a necessity along with sufficient structural waterproofing knowledge, knowledge of sources of water and how it flows through soil and interacts with structures. As a general rule the selection of sump chambers and or quantity is based upon anticipated flow and the area of the basement slab taking into account the structure and soil dynamics or typography.

A sump pump is the pump used to remove water ingress that accumulates in a water collection system.

A Pump station refers to the pump(s), pump chamber, internal pipe work and valves.

A pump station for a ground water application should always have two sump pumps.

Typically one pump station such as the Delta Dual V3 is suitable for a basement of 150m² including a light well of up to 12m².

There are two main categories of pumps (submersible and pedestal).

Submersible – submersible pumps are often known as sump pumps. A pump station containing a submersible pump will always be installed below the basement slab level (allowing ground water to gravitate toward the submersible pumps). Submersible pump stations offer visual appeal (they are concealed).  Sump pumps tend to have a longer life than pedestal pump stations.

The sump pump should be installed in a pump chamber (also known as a pump station).  Typically for basement application the sump pump would be anywhere between 500 & 1300mm below the basement slab level or even deeper, in most cases the sump in ground water application is level with the top of structural slab.

This depends on the rate of water ingress. If a new below ground structure has been built, designed well, constructed correctly and care is taken with detailing of construction joints a sump pump should run less than once a day or even not at all, this doesn’t mean that this is an indefinite condition.

Sump pumps must be maintained. We recommend a qualified engineer examines and services equipment every year. Pumps running frequently due to a higher water table, water drainage, or weather conditions should be examined more frequently (we recommend every 6 months). Sump pumps, being mechanical devices, may fail if not maintained which could lead to a flooded basement and costly repairs.

Battery backups offer peace of mind. Battery Backups will keep your pumps running during power failure, ensuring your property is kept dry; a flooded basement can result in costly repairs.  A battery backup will offer hours of additional protection from water damage in the event of power failure.