means a body of surface water—
| (a) | that is permanently or periodically open to the sea; |
| (b) | in which a rise and fall of the water level as a result of the tides is measurable at spring tides when the body of surface water is open to the sea; or |
| (c) | in respect of which the salinity is higher than fresh water as a result of the influence of the sea, and where there is a salinity gradient between the tidal reach and the mouth of the body of surface water; |
[Definition substituted by section 1(n) of Act No. 36 of 2014]