Substruck Ltd. was employed by a homeowner, through the directions of a consulting engineering firm, to complete a general investigation of the drainage at her property in Bishopstown. This was in response to recommendations of a structural survey which identified no signs of subsidence.
On arrival, we noted that the drains were completed blocked. On unblocking, we learned that the drain entering the front chamber had an obvious backfall. In fact, on surveying, we learned that the majority of this primary drain had a backfall, hence the back-up. The section between both chambers was found to be leaking at a rate of 12 litres over ten minutes which is why the homeowner did not notice the problem. A lot of the water was simply escaping from the drains!!!!
Furthermore, the drain to the public sewer was found to have settled deposits of up to 40% cross sectional area loss. We are of the opinion that these originated from the laying of the brick paving driveway some time back. Nowadays, the drain becomes a sewer at the boundary so in theory, Irish Water is responsible for this. However, as the problem originated from the private property, it would be difficult to argue that Irish Water should have to pay to clean it.
Settlement of the driveway was also noted above the line of the drain at some locations. This was most probably due to poor quality backfill and/ or poor compaction methods.
Overall, the drains were found to be constructed to a very poor standard and it highlights the requirement to ensure that competent contractors are employed to complete work and that independent supervision by an engineer or surveyor will provide extra protection for the homeowner.