THE GRAND CANAL
Edenderry and the Grand Canal The Grand Canal passes within a mile to the south of Edenderry Town linking Dublin to the River Shannon and the towns in between. This major feat of engineering was carried out in stages from 1756 onwards reaching Shannon Harbour in 1804.
A major obstacle along the route was the crossing of the Bog of Allen which lay directly in its path. The final route picked for the canal was along the northern edge of the Bog just south of Edenderry.
A branch from the main canal to Edenderry was planned as early as 1786 and built between 1797 and 1802. This canal, which is one mile in length with a cut stone harbour, was financed by the Downshire estate at a cost of £692.
A small hump back bridge was built across the mouth of the Edenderry Canal to facilitate the horses towing barges on the main line. This bridge, known as the Downshire Bridge, was financed by the Grand Canal Company and cost £55.
Another unique canal feature is the Blundell Aqueduct known locally as the “The Tunnel” which carries the Grand Canal over the Rathangan road. This was built in1793 to accommodate the proposed new road to Rathangan and gets it name from Blundell Street later named Fr Paul Murphy Street.
The building of a canal through the bog presented unique engineering problems not previously encountered due to subsidence and the difficulties in getting stability of the canal banks to retain water. A range of construction techniques were employed which resulted in high earth embankments along the stretch of canal south of the town, which was to be a constant source of problems from day one.
Breaches in the canal
Over the last 210 years there have been a number of serious breaches in the canal locally most of which were related to the building of a canal over a bog.
The first breach in the canal recorded was in August 1797 after the canal was completed and operational as far as Daingean. The breach was on the north bank near Blundell Aqueduct and took £10,000.00 and two months to repair.
These repairs gave way in January 1800 which again took several months to repair.
In 1833 a breach occurred on the Edenderry Canal which resulted in one child being drowned and the surrounding land flooded causing considerable damage. A further breach occurred on the branch canal in 1846. Both of these breaches were serious due to the high embankments and the fact that this stretch of canal is over 18miles without locks to stop the water flow.
In 1855 the main canal once again breached at the same site as 1797 & 1800 when over 200 yards of bank gave way. This repair took over 500 men over 4 months to repair. The canal was reopened on the 11th Jan 1856 and held good until 1916 when over 300 yards of canal bank gave way. This repair took 100 men ,11 weeks and £6000.00 to repair. Over 25,000 tons of clay was moved in the repairs which were carried out in extreme weather conditions including blizzards during February/March.
The most recent breach of the Grand Canal was on the 15th January 1989 when a large section of canal bank gave way, half way between the Blundell Aqueduct and Downshire bridge. Over 300,000,000 litres of water, from 18 miles of canal, drained into surrounding lands causing sever damage and flooding. The repairs were extensive and even with modern machinery took over 13 months to repair.
The whole of the canal embankment was completely rebuilt using a modern approach to this troubled spot.
Layers of 2000 guage (polytrap) polythene over compacted peat banks were used to build up the embankment before the canal itself was finally lined with polythene covered with clay and sealed with a thick layer of puddle clay.
Over 15,000 tons of sod peat was used in the building of the banks much to the dismay of locals. OPW employees worked 7 days a week to restore this stretch of canal with the final costs amounting to £1.9m (€2.41m). In recent years the Canal Harbour has had extensive renovations which extended the quay wall mooring.
The landscaping of the raised canal bank in the harbour together with the new population of ducks & swans has extended the interest beyond the traditional boaters and fishermen with many local people enjoying the tranquil walk to the Downshire Bridge or feeding the ducks.
