I did a bit of research the last few days. I’ve had a lot of conversations with engineers, with residents in around the waterways and even walked (with the landowners) across farmland in the Kerdiffstown area bordering the Waterways development. Consensus is now building as to what went wrong and it doesn’t appear that it was the Waterways at fault.
Basically a canal feeder stream took water from the Morrell river and others, ran along the back of Monread road, took onboard Naas Town Council surface water, took on N7 motorway spilloff, seemingly took some Naas waters from as far away as Lakelands.
All of this followed a trajectory entering the canal past Sallins school and behind the waterways.
Where the water entered the canal there was a double culvert arrangement, with one drain under the railway line, and another under the Kerdiffstown road. The second of these became blocked last week with the result that this very large volume of water had nowehere else to go but spill over into the surrounding fields and farmland. In addition to the immediate vicinity miles of surrounding farmland lay undrained whilst the flow could not escape.
To tackle this, the road was dug with a temporary relief trench, as per last post and a fine job was done there. To prevent this happening in future this temporary fix must become permanent with a full fledged, adequate capacity four way culvert put in there before they close the road again. The railway culvert should also be checked and probably upgraded.
The question arises how did this happen? Whilst the drainage has been historically present (since the canal was built), unquestionably the strain on these culverts has increased every year, or every decade as more and more infrastructure (such as roads with surface water) and housing has sprung up in the catchment area. Ironically the Waterways itsef was not allowed feed into here as the drain was considered at capacity. It is clear these drains should have been subjected to far greater maintenance than they were (none?) but it is less clear who is responsible. The council probably but also Irish Rail, Waterways Ireland and other agencies are in the mix. A quick annual clean should have been a basic and uncontroversial task but upgrading or replacing such works crossed more lines perhaps why it was put on the long finger.
There has been speculation in recent days that the site was a victim of poor planning and or that inappropriate rezonings were involved. I’m not sure of this. In fact the site seems to have suffered from external factors being flooded by overflowing drains from much further afield. I believe there were some blocked gullies in recent weeks but nowhere near enough to cause the flooding without massive external overload. The OS map shows flood drops, again however these are confined to one small triangle where the stream turns and which remains to this day farmland. The site itself seems an ideal location for development in many ways, being adjacent to public transport (Sallins Railway Station bang in the middle), minutes from the motorway and in the heart of commuter belt. As a mixed use development the site also features much commercial activity and has brought welcome local employment. It is an awful shame the site has not realised its potential and that some key anchor buildings remain unoccupied but fundamentally my view that it remains a good development and I hope to see it succeed as a residential, commercial and leisure hub eventually.
