The Binnian Tunnel was constructed between 1948 and 1952 and is located in the Mourne Mountains in Northern Ireland

Northern Ireland

Northern Ireland is one of the four countries of the United Kingdom. Situated in the north-east of the island of Ireland, it shares a border with the Republic of Ireland to the south and west...

. The main purpose of the tunnel is to divert water from the Annalong river to the Silent Valley Reservoir

Silent Valley Reservoir

The Silent Valley Reservoir is a reservoir located in the Mourne Mountains near Kilkeel, County Down in Northern Ireland. It supplies most of the water for County Down, surrounding counties and most of Belfast. It is owned and maintained by Northern Ireland Water Limited...

 underneath a number of mountains including Slieve Binnian

Slieve Binnian

Slieve Binnian is the third highest mountain in Northern Ireland at . The name comes from the rocky tors situated around the top of the mountain. These very rugged crest of rocky tors makes it easy to identify in views around the Mourne Mountains....

, which the tunnel was named after.

A high degree of engineering skills were employed in the building of the tunnel. Two teams of people worked at each end of the tunnel and met in the middle. The tunnel was created using drilling and blasting

Drilling and blasting

Before the advent of tunnel boring machines, drilling and blasting was the only economical way of excavating long tunnels through hard rock, where digging is not possible. Even today, the method is still used in the construction of tunnels, such as in the construction of the Lötschberg Base Tunnel...

techniques.

The tunnel was designed to carry 90 million impgals (409,148.1 m³) of water per day, be 2.5 miles (4 km) long, 7 feet (2.1 m) high and 8 feet (2.4 m) wide. When the two teams met in the middle on the 6th December 1950, they were only two inches out.

The tunnel was officially opened in August 1952.

External links

• A Century of Water from the Mournes - Part 4 (BBC)