Cill Mhuirbhigh, Inis Mór is classified as achieving Excellent Water Quality in 2025 based on the assessment of bacteriological results for the period 2022 to 2025. Cill Mhuirbhigh, Inis Mór has achieved an Excellent Water Quality rating for the 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.

Cill Mhuirbhigh beach is a sheltered sandy shore bounded by rocky shore to the west and east. There is a small area of marram dune which supports a variety of vegetation. The habitat of Machair is located within Cill Mhuirbhigh and this form of coastal grassland supports a variety of rare plants. There is also a variety of animal and bird species including rare species. The rarer plants are listed in the Irish Red Data Book and legally protected under the Flora Protection Order (1999). There is a UNESCO World Heritage Site on the island, the prehistoric fort Dún Aonghusa. The whole island is significant in terms of cultural and environmental value.