Bertra Beach, Murrisk is classified as achieving Excellent Water Quality in 2025 based on the assessment of bacteriological results for the period 2022 to 2025. Bertra Beach, Murrisk achieved an Excellent Water Quality rating for four consecutive years 2022 to 2025. Annual water quality ratings are generally calculated using monitoring results over a four-year period and are assessed against stringent bacterial limits to protect bather health.

Bertra beach consists of a sandy dune area with the centre of the designated bathing area enclosed by caged stone. Bertra Beach is an exposed beach and can be subject to rip tides/strong currents. The sand dunes consist of embryonic dunes and marrram dunes both of which are listed under Annex I of the EU Habitats Directive. Restoration work on the sand dunes due to erosion has taken place over the last decade and has reduced the extent of the erosion. Bertra Beach forms part of the Clew Bay Complex (SAC & SPA) Site Code 001482. In close proximity to Old Head Beach is Old Head SAC/pNHA (Site Code 000532). Bertra Beach lies at the foot of Croagh Patrick. Activities include swimming, surfing, canoeing and angling. The bathing water is approximately 1km2 in area. The medium and the maximum water depth within the designated bathing area is 0.5m and 5.0m respectively depending on the tides.