Bunmahon Beach is classified as achieving Excellent Water Quality in 2025 based on the assessment of bacteriological results for the period 2022 to 2025. Bunmahon Beach achieved a Good Water Quality rating in 2024 and Sufficient Water Quality rating in 2023 and 2022. 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.

Bunmahon is a sandy gently sloping beach with a dune area along the roadside. Currents can be variable. The Dune area supports a variety of plant species and wildlife. The rock pools which are accessible during low tide support a variety of marine wildlife and plants. The United Nations Economic Social and Cultural Organisation (UNESCO) has recognised the south coast of the county between Garrarus and Ballyvoyle Head as a GeoPark; one of a network of European sites of exceptional geological interest. The coastal area is also a Special Protection Area (SPA) under the E.U. Birds Directive. The designated bathing area is approximately 500 metres long and 100 metres wide (at low tide).