The Styx River Boating Reserve provides boat ramp access to Brooklands Lagoon, an elongated tidal estuary near Brooklands, Christchurch.

The lagoon sits at the mouth of the Waimakariri River, is approximately 270 hectares in size, and is sheltered from Pegasus Bay by Brooklands Spit. Spring tides push around 1.

6 million cubic metres of water through the system, making tidal timing important for boaters. The reserve is a popular launch point for kayaking and trailer boats.

A roughly 10-kilometre kayaking circuit can be completed by launching at the Styx River mouth and paddling the lagoon with the tide.

The shallow tidal flats attract a variety of wading birds, and the surrounding reed beds and wetlands offer notable wildlife viewing alongside the open water.