RIVER CONTROL

Bay of Plenty Beacon, Volume 6, Issue 81, 15 June 1943, Page 5

RIVER CONTROL

RANGITAIKI PLAINS DRAINAGE

DEPARTMENTAL REPORT

Tliq. annual report on the Rangitaiki land drainage fjy the Lands and Survey Department, states that on September -I, 19 J2, flood stage* in the Rangitaiki River from Edgccumbe down-stream were lit to 2i't above tlie 1925 flood levels, and the fact that a recent flood, passed down the- river with only slight overflow above Edgecumbe can be attributed principally to the fact that the lower reaches of the river had been recently cleared of willows. Stopbanking Scheme "There may lie uncertainty as to the economic .soundness of. a comprehensive stop-banking scheme. I'or the Rangitaiki River," states the report, "but there can be no doubt that the annual expenditure necessary to control the willow growth along the. river-bank provides a protection against medium Hoods which the district cannot all'ord to be without. "The mouth of this river moves along the coast eastwards, A direct outlet to the .sea was opened across the sand-spit which formed between the river and the sea in June, Unsuccessful attempts were made to re-open the original mouth in 1942. On September 4, 1942, when the. river was in high flood the mouth Avas reopened Avith very little trouble by a drag-line excavator a few chains east of the direct approach of the river to the sea. LVi a period of live years, the eastward travel of the riA-er mouth, Avas approximately one mile. In regard to the Tarawera River,, the report states: "Mention has been made in previous annual reports of the necessity for a substantial stopbank along the left bank of the Tarawera River. This is required for the protection of the sAvamp area between the river and the western hills and also as a safeguard against the possibility of. the river leaving its present channel.

"The moutli of this river moves westwards, and it is difficult to account for the fact that this movement is in the opposite direction to that of the Rangitaiki River mouth. The westerly movement of the mouth of the Tarawcra lias been prevented for some years by a stone training vail. During_ last winter the river breached this training wall some distance from its seaward end and the river mouth moved rapidly westwards, levelling the Avail l.or a distance of about liOOlt from its outer end."