Why is my Basement Cellar Flooding?

Why is my Basement Cellar Flooding?

Waterproofing articles

The basics of why your cellar/basement may be flooding, and thoughts on what questions to ask, and what steps to take, in what order.

Why is my cellar flooding - Q 1

If the space is suffering water ingress, does that ingress continue constantly and at a constant rate, or is it in association with rainfall?


If the ingress is constant, it can indicate that the water is lost from pressurised services such as water mains (speak to a drainage specialist or the utilities provider). If it occurs in association with rainfall, then it is related to rainfall (more on this below).

Why is my cellar flooding - Q 2

Does the water have an oily sheen floating upon it?


Water with an oily sheen and in some cases, a black colouration, usually indicates escape of water from drains handling foul content. Either source a drains survey is the affected drains are likely private, or contact the utility provider if they are public.

Why is my cellar flooding - Q 4

If the issue occurs in association with rainfall, are the surface water drains defective?


It could be related to escape of water from surface water drains, i.e. those that remove water collected by roof's etc., it may be prudent to have the drains surveyed and repaired if necessary (we have advised this in the past when taking phone enquiries and people have called us back advising success). You could potentially introduce drain dye available from builders merchants and see if any shows within the cellar. Note that issues with drains can still arise in association with issues of groundwater pressure, and so fixing.

If you are experiencing problems get in touch with a Structural Waterproofing Contractor who will investigate the problem.

Why is my cellar flooding - Q 4 & 5

What's the topography? What type of soil is the structure in?


There are some other factors which can influence water accessing the ground, such as the rate of surface water infiltration through finishes, things like gravel driveways for example will not prevent water readily accessing the ground, but topography and soil type are bigger influences. If suffering water ingress, is the property on low lying ground? At the the bottom of a hill or river valley? Such property has chance of sitting within true water table. If the ground is clay, the topography is less of an implication because water can 'perch' within cohesive impermeable soils such as clay, and as a result basement property on top of a hill can still come under hydrostatic pressure. To understand more about water tables, you can read our article here.

If you can ask and answer, these questions, and you reach the point where what you have is an issue of groundwater penetration, and you require assistance with this, get in touch.

Other related Trace articles which you may find of assistance

Understanding Water Table and Basements.

Groundwater pressure and basements.

About Trace Basements

We are Waterproofing Design Specialists in dealing with flooded basements, if you've answered the questions above and need assistance with a groundwater ingress issue, please contact us.

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We work across the full range of commercial property, with particular specialisms in retail, offices and warehousing. Our team is built around expertise and knowledge, providing clients with premier independent advice.

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