ARAPUNI LAKE

Waikato Times, Volume 124, Issue 20841, 27 June 1939, Page 6

ARAPUNI LAKE

RAISING THE LEVEL ELIMINATING WATER SHORTAGE FULL LOAD TAKEN AT WEEK-END In a further attempt to conserve flood waters on the Waikato River so that the supply of water to the turbines at the Arapuni power station may be more constant, flashboards are being erected on the spillway. The work is expected to be completed within three weeks. The new work will make provision for raising the level of the Arapuni Lake about four feet, because flood waters which may be expected during periods of heavy rain in the winter will be prevented from flooding over the spillway. Swollen waters from the Spring thaw at Ruapehu will also be conserved in Arapuni Lake. In addition to giving a bigger storage at the lake, the flashboards on the spillay -will increase the head of water on the turbines, with the result that a little more power will be generated with the same amount of water as at present. Eliminating Water Shortage The new scheme is subsidiary to the project for the erection of control gates at Lake Taupo, which have also been planned to regulate the flow of water in trxe Waikato River so as to eliminate, if possible, a recurrence of the shortage of water which reduced the output of the station during the dry spell in the summer. The raising of the level of Arapuni Lake may mean that many boat-own-ers will And that sheds built near the normal lake level will now become partially submerged. Owners would be advised to check the level and situation of sheds before the new scheme is completed about the second week in Sulf. Water Flows Over Spillway For the first time for many months water of any appreciable amount flowed over the spillway for a few hours on Sunday. Heavy rain during the week had raised the level of the river considerably and about a foot of water was lost. The steam plants in both Auckland and Wellington, which have been used far more this year than ever before, were shut down for a time and Arapuni generated at full capacity. Even then some water was lost. It Is to preserve the extra flow- in such cases that the flashboards are being erected, for the extra head would be valuable when the flow returned to normal, as it has this week. It is the intention of the engineers to waste as little water as possible at Arapuni, for with the ever-increasing demand for power and the enlarging of the power units at the station, the plant will require the full capacity of the Waikato River. Bringing Scheme to Completion The work of Increasing the capacity of Arapuni is now under way, a start having beeu made on boring the two additional penstock tunnels which will bring the strength of the station to eight units. Tunnelling will he slow, however, and the work is cx- ! pected to occupy a year. The con- ! tracts have been let for the two addi- | tional turbines and the two extra j generators. Six turbines are at prei sent operating. ! With the installation next year of j the two new units, the full scheme at ! Arapuni will be completed. Then the j public Works Department will have Ito consider the establishment of a j new hydro-electric scheme on the ! Waikato River to meet the ever-in-creasing power demand in the North Island. Already several sites have been considered and this week tenders close in Wellington for the task of boring to take rock tests at various sites. At the present time Cambridge appears to be one of the favoured sites for a new power station.