1960-61 VICTORIA SOIL CONSERVATION AUTHORITY ELEVENTH ANNUAL REPORT FOR YEAR ENDED 30TH JUNE, 1960 PRESENTED TO BOTH HOUSES OF PARLIArviENT PURSUANT TO ACT No. 6372. (App,....imate Oost of Repo.-1:-Preparation--Not Given. Printing (1,400 copies), .\1395. By Authority: A. C. BROOKS. GOVERNMENT PRINTER. MELBOURNE. No. 30 --[2s. 9d,]-9497/60. SOIL CONSERVATION AUTHORITY Chairman: G. T. THOMPSON, L.S., A.M.I.E. (Aust.) Members: R. G. DOWNES, M.Agr.Sc., M.A.I.A.S. R. G. THOMAS, M.Agr.Sc., M.A.I.A.S. Secretary: ARTHUR TIDD The Hume Reservoir near Bethanga Bridge. Soil conservation is vital to the continued efficiency of the State's water storages. SOIL CONSERVATION AUTHORITY ELEVENTH ANNUAL REPORT FOR THE YEAR ENDED 30th JUNE, 1960 Under the provisions of the Soil Conservation and Land Utilization Act No. 6372 (1958), the Soil Conservation Authority has the honour to present to Parliament its Annual Report for the year ended 30th .June, 1960. Several events of particular significance to soil conservation have occurred m Victoria during this year. The Parliamentary Public Works Committee, as a result of its enquiry into the need for the enlargement of the Eppalock Reservoir, recognized the urgent need for soil conservation and erosion control work to be undertaken in the catchment to protect the proposed new water storage. Accordingly, it recommended that £50.000 a year should be made available for this work for a period of ten years. This will be the first time in Australia when funds have been made available for conservation works throughout the whole of a catchment to a new reservoir. The same Committee, when considering the establishment of a Glenelg River Improvement Trust, came to the conclusion that the success of any river improvement work to be undertaken by such a body would depend on soil conservation and erosion control work being carried out concurrently in the catchment. 4 These recommendations indicate that there is a growing appreciation of the advantages of co-ordinated soil conservation and erosion control work over large areas in catchments and the Authority now has the opportunity of applying principles of co-operation in soil conservation which were put forward in the last Annual Report. Another event of particular interest to the Authority was the enquiry by the State Development Committee into the use of timber resources in the catchments of the State. Many emphatic statements on this subject have been made by various parties in dispute. The Authority considers that the resolution of the dispute can only come from an expanded programme of hydrological investigations carried out by a completely impartial body. The Authority is such an impartial body established to consider and determine land-use within water supply catchments and to undertake any investigations needed to provide information for making such determinations. PROCLAMATION OF CATCHMENTS. The decision to proclaim an area as a water-supply catchment is made following consultation with the Land Utilization Advisory Council, which was constituted for the purpose of making recommendations to the Authority regarding definition and constitution of catchments and the land-use policy within the proclaimed area. A proclamation thus gives the Authority the power to determine the most suitable use in the public interest of all lands in the area. It can also determine the conditions under which various forms of land-use are to be permitted. During the past year, six more catchments have been proclaimed and two others were reproclaimed after revocation because of boundary considerations. The land-use determinations which have followed proclamation during the yeaT or are to follow shortly, are meant to serve particularly the interests of the various Waterworks Trusts administering the domestic supplies of towns round the Macedon area, Kyneton and Geelong. An earth flow in granite country near Berringama in the Hume C<ftchment. 5 CONSERVATION IN WATER-SUPPLY CATCHMENTS AND LAND USE DETERMINATIONS. Work was commenced in September, 1959, on land-use determinations in the water supply catchments on the Macedon Range. Two preliminary surveys had already been made on Riddell's Creek Catchment and Lancefield Catchment. The first allotment-by­ allotment survev had been made with the aim of land-use determination in the Riddell's Creek catchment. At the same time general ecological and land-use observations were made over the whole of the Macedon Range catchments to obtain an overall concept of the environment. With the completion of a detailed survey in the Riddell's Creek Catchment, and with additional field work in the other catchments, a general approach to land-use determination was formulated. This approach was based primarily on the needs of the community for a " clean, adequate, and reliable " water supply. The criteria involved are quality of water, the quantity, and its rate of release from the catchment. The land-use must, therefore, be determined in relation to its effect on turbidity and contamination and on the hydrologic cycle. Conditions should favour maximum absorption into the soil, and release of water as subsurface flow rather than surface run-off. Such conditions automatically create the lowest erosion hazard, and thus favour the clearest flow of water. More knowledge is needed of the effect of various types of land use on infiltration, water-holding capacity, and erosion. It must, therefore, be expected that the Authority's determinations will be on the conservative side to ensure adequate protection of water supplies. Keeping the relevant clauses of the Soil Conservation and Land Utilization Act in mind, there are two main stages:-- (1) General Stage-the determination of suitable forms of land-use, e.g., forestry, pasture, and agriculture. (2) Specific Stage-~the conditions of each form of land-use, e.g., methods of clearing, rotations. The natural timber has been retained wisely on this steep slope which could easily become seriously eroded if ~ompletely cleared. 6 Stage 1, therefore, lends itself to the formulation of general categories which could be used to indicate the form of land-use for each part of the catchment. In a catchment devoted to forestry only, where the land is designated as State or Reserved Forest, such diverse categories are not necessary. However, in most water-supply catchments, there is Crown land, State :Forest, and alienated land, either cleared and being used for pasture or agriculture. or under forest, scrub, or bracken. The determination must cover the land devoted to roads, reserves, and residential areas if any, and special consideration is required for the streams and the adjoining land. For the .M.acedon catchments, eight general categories have been formulated to cover all forms of land-use. These categories are to be used as a basis for the specific conditions which will be imposed on properties where necessary. For mapping purposes on an allotment basis, these categories are probably only suited to small catchments of the order of 2~5 square miles, or sub-catchments within a larger catchment. The categories are as follow :- 1. Land which should be permanently used for forest purposes where forestry operations shall be restricted to the minimum required for proper forest maintenance to keep the forest in good condition as imposed by the Authority, or as required by the Forests Commission acting as agent for the Authority. 2. Land which should be permanently used for forest purposes where commercial logging operations may be carried out under the supervision and control of the Forests Commission acting as agent for the Authority. 3. Forested land, which if approved by the Authority, may be used for pasture or for agriculture, subject to conditions imposed according to the particular circumstances, the conditions to include, among others, the degree of clearing permissible and the specification of those areas where timber shall be retained. 4. Cleared land at present carrying bracken or other protective vegetative cover on which there shall be no change of land-use except with the approval of and under conditions imposed by the Authority. 5. Cleared land suitable for pasture or for agriculture, subject to conditions imposed by the Authority for the particular circumstances. 6. Land within one chain, or such a greater distance as the Authority may specify from specified streams, springs, o:fftakes, and storages on which land-use shall be subject to conditions imposed by the Authority, but in no circumstances shall cultivation or erection of buildings be permitted. 7. Land which may be used for residential purposes, subject to provisions of other relevant Acts. 8. Land reserved for roads and other public purposes on which any changes from the existing nature and conditions shall be made only after consultation with the Authority. Categories 1-3 deal with forested land, and require additional comment. In No. 1, forestry operations are restricted to a minimum but may, nevertheless, involve the extraction of some trees with the aim of maintaining a satisfactory stand of timber. Many areas around Macedon were logged in rather haphazard fashion in the past, leaving a small percentage of tall trees and a large amount of young regenerating timber or coppice growth, with low, useless scrub. Category No. 2 implies that there is a significant amount of millable timber at the time of determination, and conditions are suitable for some extraction. Category No. :3 implies that some part(s) of the forested area could reasonably be cleared, under supervision, for some form of agriculture, the remainder of the area to be kept under permanent forest. During the year, joint meetings have been held between members of the Waterworks Trusts, Forests Commission representatives, and the District Conservation Officer and Investigating Officer dealing with the catchment determinations. These meetings are aimed at keeping all relevant bodies informed on the Authority's work, and to enable discussion and criticism.