Here we are at the springs and the little bay they flow into. It stays fresh water for quite a ways.

Kawa'a Springs, located on the Big Island of Hawaii, is a natural spring that feeds a brackish pond at Kawa Bay, known for its sandy bottom and suitability for wading and swimming.
Repeatedly a flash-point for coastal-access and land-rights issues, Kawa Bay is now a quiet, pebbly cove. It's bounded by a creek and cliff-top heiau (temple) on one side, and Kaʻalaiki, the island's second-largest freshwater spring system and fishpond estuary, on the other.

be careful as there are a number of strong currents, which pull people off shore, most recently in March of 2003 a local man, harvesting 'opihi (a type of limpet) from the rocks, was sucked out to sea and drowned.