Skip to main content


Altnaghree Burn

Altnaghree Burn is a tributary of the River Dennet. It has some of the Foyle area’s highest densities of native fish including Atlantic salmon, sea trout and brown trout.

The lower reaches of Altnaghree are dominated by a series of small waterfalls which limit the movements of migratory fish to certain flow conditions.

Typically, returning salmon and sea trout begin ascending the Altnaghree in suitable spates from July and stay in deeper water until spawning time. Spawning usually starts in September for brown trout, in October for sea trout and December for Atlantic salmon.

Over the past ten years, Loughs Agency has undertaken a number of pre-spawning sea trout surveys. A better understanding of fish numbers, distribution and habitats has helped us to develop a series of habitat improvements.

At Altnaghree, these include:

  • erecting riverside fencing
  • installing pasture water pumps
  • hard and soft bank protection
  • trimming trees and bushes
  • adding stones to narrow over-widened areas and providing fish cover
  • pinning large wooden debris to protect banks, and scouring and cleaning gravel.

Loughs Agency is always eager to develop collaborative projects with local partners. If you belong to an organisation which is interested in protecting and improving local aquatic habitats, please contact

Her Majesty Queen Elizabeth II

21 April 1926 to 8 September 2022