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Shallow Drains For Reducing Waterlogging And Salinity On Clay Flats, Don Mcfarlane, Tim Negus, Arjen Ryder

Journal of the Department of Agriculture, Western Australia, Series 4

Flooding, waterlogging and salinity are problems which commonly occur together on the broad valleys of the wheatbelt. Drainage lines often become poorly defined once they reach the valleys and flood waters spread out, causing inundation and waterlogging. This excess water needs to be controlled because it contributes to salinity

Seepage Interceptor Drains For Reducing Waterlogging And Salinity, Don Mcfarlane, Jim Cox

Journal of the Department of Agriculture, Western Australia, Series 4

Shallow interceptor drains can reduce waterlogging on sloping sites. Such drains will more than pay for themselves from the increased crop yield. Recent work has shown that these drains also decrease salinity so that they are cost-effective in the long as well as the short term.

Level Banks Used To Decrease Waterlogging Can Increase Salinity, Don Mcfarlane, Richard Engel, Arjen Ryder, Maurice Eales

Journal of the Department of Agriculture, Western Australia, Series 4

Some farmers have used level W1SALTS banks to control surface zvaters above areas affected by ivaterlogging and salinity. Because the amount of waterlogging has been reduced, crop yields have increased downslope of some banks. However, the banks divert fresh surface water into deeper salty groundwater and, in the long term, worsen salinity. This article details an investigation of the effect of level WIS ALTS banks on saline groundwaters and discusses alternative methods of preventing the waterlogging of saline areas.

Economics Of Interceptor Drains : A Case Study, Andrew Bathgate, Ian Evans

Journal of the Department of Agriculture, Western Australia, Series 4

This case study determines the most likely rate of return to capital invested in constructing seepage interceptor drains to reduce the effect of waterlogging on crop and pasture yields. The analysis of a farm in the Denbarker region, west of Albany, determined what increases were needed in pasture growth to justify the cost of constructing drains across four adjacent paddocks. The benefits of changing rotations to include lupins were also determined, as growing lupins was unprofitable before the construction of drains.

Mogumber Drainage Works Succeed, L K. Lenane

Journal of the Department of Agriculture, Western Australia, Series 4

The loss of arable farmland from soil erosion, waterlogging and salinity is a severe problem on some Western Australian farms.

When the arable land comprises only 40 per cent of the total area within the Mogumber Soil Conservation District, this loss is a real cause for concern. So too is the resulting damage to roads, siltation of railway culverts, and deaths of roadside trees from rising saline watertables.

However, drainage, contour and other works undertaken by the Mogumber Soil Conservation District have halted this degredation. Badly eroded areas that were fenced off now have a satisfactory ground cover. A wheat …

Seepage Interceptor Drains And Topsoil Salinity, T R. Negus

Journal of the Department of Agriculture, Western Australia, Series 4

The Department of Agriculture established 121 trials in its Narrogin advisory district starting in 1972 to measure the effect of bulldozer and grader built seepage interceptor banks and drains on the topsoil salinity of the land downslope of them.

After 14 years of moniterin, there was no evidence that seepage interceptor drains and banks reduced the top soil salinity on 10 of the 11 sites in the Pingelly, Brookton and Wickepin Shires.

Draining Irrigation Areas, K S. Cole, J P. Middlemas

Journal of the Department of Agriculture, Western Australia, Series 4

Many irrigation schemes throughout the world have turned into unproductive saline flats and swamps. This dramatic change can occur within a few years of irrigation starting and has been part of irrigation schemes from earliest times up to the present day.

The main cause of this salinisation is normally excess irrigation water use combined with poor drainage. Any form of waterlogging will have an adverse effect on plant growth.

Drainage To Control Waterlogging, D J. Mcfarlane, T R. Negus, J W. Cox

Journal of the Department of Agriculture, Western Australia, Series 4

Drains can be classified in several ways. Drains on flat land have similar drainage effects on either side of the drain and are called relief drains. Drains on sloping land intercept seepage water moving down hillsides and therefore have most effect on the downslope side. They are called interceptor drains.

Drains can also be classified as being open drains (that is, open at the ground surface) or buried drains (for example, tube drains).

Drainage Prospects For Saline Wheatbelt Soils, P R. George

Journal of the Department of Agriculture, Western Australia, Series 4

Sub-surface or groundwater drainage by buried tube drains or open ditches can reclaim saltland in the Western Australian wheatbelt. However, this method is expensive and not all sites can be drained cost-effectively. Each drainage site is unique, so careful investigation of each site is essential before recommendations on drainage method and design can be made.

Draining A Saline Seep, W J. Burdass

Journal of the Department of Agriculture, Western Australia, Series 4

Sub-surface drains have dried out a salty seep on farm land in the Katanning district. Capeweed and clovers are now growing on more than three-quarters of the land that was previously bare or carried only patchy sea barley grass.

The drains are still running water after five years. The salt content of the surface soil has been reduced markedly and the salt content of the effluent water is decreasing.

However, to complete the reclamation, further drains will be necessary. Both existing and any new drains will have to be flushed periodically because blockages of pipes cause problems.

Interceptor Drains And Waterlogging Control, J W. Cox, T R. Negus

Journal of the Department of Agriculture, Western Australia, Series 4

Department of Agriculture trials of seepage interceptor drains from 1972 to 1983 primarily assessed the effects of such drains on salt encroachment. Although these trials showed that the drains had little influence on salt storage within the topsoil, they did reduce waterlogging downslope.

To investigate this drainage effect further, the Department's Narrogin office surveyed 35 drains on 14 properties in the winter of 1981, followed by detailed crop measurements in December that year. Provided the drains were properly designed, surveyed and constructed, and well maintained, they could be expected to increase crop yields during a waterlogging year by about 1 …

Drainage And The Law, G A. Robertson

Journal of the Department of Agriculture, Western Australia, Series 4

Drainage is being increasingly used in Western Australia as an attempted cure for land salinisation and waterlogging. This is nor surprising as drainage is a technical approach that has, in some cases, improved saline land and reduced the effects of waterlogging. However, drainage is not always successful or cost-effective. A detailed site assessment is required before any large or costly drainage system is attempted. Articles in this issue of the Journal of Agriculture discuss that aspect in detail.

Soil Types And Drainage, Eric Bettenay, N. J. Schofield

Journal of the Department of Agriculture, Western Australia, Series 4

At least 90 per cent of the phosphorus entering the Peel-Harvey estuarine system comes from land cleared for agriculture, most of it from the coastal plain. These soils are naturally deficient on phosphorus and sulfur and this is supplied in superphosphate, which contains about 10 per cent phosphorus and 1 percent sulphur.

However, rain leaches some of this applied phosphorus from the land into drains and rivers which flow into the estuary. In 1981, farmers in the Harvey River-Mayfields Drain catchment lost the equivalent of 1,300 tonnes of superphosphate into the estuary. Between them they have in effect spent $120,000 …

A Central Midlands Catchment Study : The Prospects For Land Drainage, B J. Hillman, B. J

Journal of the Department of Agriculture, Western Australia, Series 4

Flooding, waterlogging and salinity problems in Western Australia are complex. Usually broad areas of land are affected, thus it is hard for one farmer alone to combat the effects because the problem so often starts and finishes off his farm.

Deep Drainage As A Method Of Treating Saltland, Eric Bettenay

Journal of the Department of Agriculture, Western Australia, Series 4

In some situations, deep drainage may be warranted to return salt-affected land to full production.

This method is being investigated at CSIRO's Yalanbee Experiment Station.

Landform, Natural Drainage And Salinity, Eric Bettenay

Journal of the Department of Agriculture, Western Australia, Series 4

An understanding of salt movement in streams and groundwater may lead to better methods of control and prevention of salinity.

Flooding And Salt Problems In The Wheatbelt, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

VALUABLE land has become salty in parts of the West Australian agricultural areas because most of the surrounding land has been cleared and developed for agriculture.

This salting of a small proportion of the land is part of the price paid for the development of agriculture in this State.

Drainage is not the answer to the wheatbelt flooding and salt land problems.

A more practical approach is to limit runoff from sloping land, and to make good use of salt-affected land by growing salt tolerant perennial pastures on it, says the Soils Division of the Department of Agriculture.

Orchard Drainage, R G. Cahill

Journal of the Department of Agriculture, Western Australia, Series 4

UNDERGROUND drainage of orchard land is an essential feature of fruitgrowing which is overlooked by many orchardists.

Soils should be adequately drained to cope with all winter rains.