for chief surveyor
Joseph Thomas|254x254px Sumner is nestled in a coastal valley separated from the adjacent city suburbs by rugged
volcanic hill ridges that end in cliffs that descend to the sea shore in places. Sumner Bay is the first bay on the northern side of
Banks Peninsula and faces
Pegasus Bay and the
Pacific Ocean. Because of its ocean exposure, a high surf can form in some swell conditions. The beach is gently sloping, with fine grey sand. It is a popular surf beach for these reasons. Sand dunes have filled the river valley behind the beach. This has made housing construction relatively easy, although flooding at the head of the valley has been a problem in the past due to the reverse slope caused by the sand dunes filling the front of the valley. This has been addressed by a flood drain. A sea wall and wide esplanade have been built along the length of the beach to prevent coastal erosion. The rocky volcanic outcrop of
Cave Rock, or
Tuawera dominates the beach. Until the mid-1860s, this feature was known by Europeans as Cass Rock, after the surveyor
Thomas Cass. There are other rocky outcrops in the area and the volcanic nature of the geology is readily apparent from several of the exposed cliffs around the valley.
Shag Rock, or
Rapanui, is another large volcanic outcrop at the western end of the beach and sits at the mouth of the Estuary formed by the Avon and Heathcote rivers. This landmark was shattered by the Christchurch earthquakes in 2011, which reduced the iconic rock to a pile of boulders. The outlet of the
Avon Heathcote Estuary, at the western end of the beach, forms the Sumner bar off shore of Cave Rock. The Sumner bar presents a major hazard to shipping, while the fast currents, strong rips and undertows in the area can be a danger to swimmers. In December 1854, Commander
Byron Drury, in
HMS Pandora, surveyed the Sumner Bay, including the bar and mouth of the
Avon-Heathcote Estuary for the
Canterbury Provincial Council. Drury wrote a report and produced a detailed chart of the area, with soundings. Commander Drury's 1854 chart locates several buildings on shore, including a store at the foot of the hill in Clifton Bay, Day's house, which is set well back from the foreshore on a bend in the road, as it turns away from the foot of Clifton hill, and Dobson's house, which is shown at end of the spur at the foot of Richmond Hill. Compared to a modern-day map, the Day's house would have been near the corner at the top end of Nayland Street while Dobson's house would be near the intersection of Nayland Street and Wakefield Avenue. The earliest recorded accident crossing the Sumner Bar occurred in May 1845 when a whaleboat capsized, without loss of life. The cutter
Hawk broke up crossing the Sumner Bar in rough weather at the end of June 1851 and wrecked on the beach, though the crew survived, the cargo was plundered. Fifteen more vessels were recorded as stranding on the bar between 1851 and 1867, with 7 being total losses. One regular vessel crossing the bar in the early days was the
Mullogh, New Zealand's first iron hulled steamer. On 25 August 1865 the
Mullogh ran onto Cave Rock, Sumner, in violent surf. Her cargo of liquor created keen interest on the beach. George Holmes of Pigeon Bay, the contractor for the
Lyttelton Rail Tunnel, then bought the ship, refitted and used her until 1869. The
NZ Trawler Muriel was stranded on Sumner Beach in 1937 and was a total loss and had to be dismantled where she lay. ==Community==