Historic Poverty Bay and the East Coast, N.I., N.Z.
Gisborne's Water Supply Problem
Gisborne's Water Supply Problem
Gisborne's misfortune in not being blessed with a plentiful, nearby supply of water for domestic purposes was first noted by Captain Cook. A spring near the site now occupied by the Wi Pere memorial in Read's Quay had to be relied upon by the pioneer residents when their tanks and wells failed. Many water supply schemes have since engaged the attention of the civic rulers. At the outset it was believed that an artesian supply could be obtained, but all the bores that were put down were a failure. Waihirere, as a possible source of supply, was first suggested in 1886. A poll taken in 1902 (in conjunction with a sewerage scheme) to draw water from that locality was carried, but, when the issue was voted upon again in 1903, it was rejected.
The contract in connection with the Te Arai supply was let in May, 1906, the ratepayers having approved, by 583 votes to 156, the raising of £75,000 for the purpose. By 1912 it was found, on account of the steady growth of population, that the supply, during dry spells, was not equal to the demand. Whilst a settling tank was being constructed at Waingake in 1913, a tunnel collapsed, and three workmen—Harry Fletcher, Robert Houston and Frank Wild—were killed. This was the worst accident ever experienced in connection with a Gisborne borough undertaking.page 393
To augment the supply a pipeline was laid, in 1917, from the Mangapoike stream over the watershed to the Te Arai side, and a pumping plant was installed. Within a few years, however, the demand exceeded the combined supply during drought periods. A service reservoir (850,000 gallons) was built on Taumata Hill in 1934, and proved helpful chiefly for firefighting purposes. In October, 1942, the ratepayers agreed to the raising of £45,000 to enable a low-lying area (including some ponds) in the Mangapoike watershed to be converted into a 40-acre reservoir, with a capacity of 246 million gallons. This scheme was designed by G. F. Clapcott (borough engineer).
Upon the advice of a consulting engineer, a start was made to construct a 6,000-foot tunnel to allow the water from the dam to be led direct into the Te Arai watershed. As the formation proved unstable, it became necessary to lay a pipeline 3¼ miles in length from the dam to a point where the ridge required to be pierced by a tunnel only 80 feet long. A reinforced tank (capacity, 420,000 gallons) in Lytton Road was, at this stage, added to the scheme. These extra works called for a supplementary loan of £30,000.
So desperate did the supply position become during the drought early in 1946 that the need to draw water from the Waipaoa River was obviated only by a narrow margin. Prior to the start of a drought of five months' duration during the spring and summer of 1947–8, only 40 million gallons of water had accumulated in the dam. In March, 1948, two pumps were installed alongside the Matawhero bridge to pump water from the Waipaoa River into the town mains. On the day before pumping was to have begun the awkward position was relieved by soaking rains. A torrential downpour in May, 1948, filled the dam to capacity.
Laid down in 1907, the 15-inch main from the Te Arai headworks was guaranteed only for between 25 and 30 years. In June, 1948, G. M. Beaumont (borough engineer) estimated that a 20-inch main capable of delivering 2,350,000 gallons of water per day, together with the work of extending the Taumata Hill reservoir so that it would hold 5,000,000 gallons of water, and other necessary work, would cost £211,320. His plan, he said, would provide for the needs of a population of 23,500, which, at Gisborne's rate of progress, should be reached between 1965 and 1970. With the aid of booster pumps, the capacity of the proposed larger main could be increased to supply a population of 40,000 on a consumption basis of 100 gallons per capita per day.