McCarrs Creek is located on the western side of the Pittwater peninsula in Sydney's Northern Beaches region, flowing into Pittwater and providing access to Ku-ring-gai Chase National Park. The creek and its surrounds are characterised by natural bushland and secluded waterfront settlements that are not accessible by road — the only way to reach them is by boat across Pittwater or on foot through the national park.

The primary access point for paddlers is McCarrs Creek Reserve, which offers free parking and an easy put-in. Church Point, on McCarrs Creek Road, also serves as a convenient hand-launch location, though parking there is limited and planning ahead is advisable. The Church Point ramp is particularly useful for those heading toward Scotland Island, Elvina Bay, or Lovett Bay.

A popular route from McCarrs Creek Reserve is the paddle around Scotland Island, approximately 9 kilometres return. Paddlers can also continue further up into Pittwater, past The Basin and toward Palm Beach, a one-way distance of around 9 kilometres. These options place McCarrs Creek within a broader network of Pittwater routes that can be extended or shortened depending on conditions and preference.

Canoeing, kayaking, and stand-up paddleboarding are all permitted on the water. The surrounding Pittwater area includes moored yachts and boat traffic, which paddlers should be aware of when planning routes. The creek itself opens into the broader Pittwater estuary, where conditions can vary depending on wind and tidal movement.

The area's appeal lies largely in its access to foreshore-only communities and undeveloped bushland within the national park, making it possible to explore parts of the Sydney region that remain largely untouched by road infrastructure. Wildlife in the broader Pittwater and Ku-ring-gai area includes white-bellied sea eagles and brahminy kites, species noted in the region's paddling literature.