Work on the northern junction of the new Co Monaghan bypass was postponed for a few days last week when a bird's nest with unhatched eggs was discovered along the route.
The discovery was made on a bank of the Longfield River in Carrickmacross close to the new bypass northern interchange, just off the Castleblayney Road.
Contractors Jons Moneley said yesterday it estimated the delay cost "a considerable sum" but it had not quantified the figure.
The nest was discovered by officers of the Eastern Regional Fisheries Board. Ms Trina Finnen, a National Parks and Wildlife Service conservation ranger with the Department of the Environment, said the contractors did not have to stop work but they agreed to hold back for up to a week or so to see if the eggs would hatch. She said all the workers onsite took an interest in the water hen's welfare.
Last Friday the eggs hatched. The nest, newly hatched chicks and mother hen were later successfully moved down stream.
"The fact that we waited for the eggs to hatch was, in fact, good for morale and for the overall goodwill of the project," a Jons Moneley spokesman said.