Landcare - Warburton Project

Stage 1 - February '91           Stage 2 - February '92      <<Quick links

This project (Feb. 91 and Feb. 92) has been one of the most successful Landcare projects across the Ngaanyatjarra, Pitjantjatjara and Yankunytjatjara lands. Warburton, which is on the Ngaanyatjarra lands has a very low rainfall of approximately 80 to 90 mm. per annum.

The land management adviser with Pitjantjatjara Council (Mike Last) first visited Warburton in the spring of 1974. At that time he was living with his family at Ernabella on the Pitjantjatjara lands, approximately 650 kilometres to the east in the top end of South Australia. Mike had been studying the micro-catchment system which was being used in the Negev desert in Israel. This system of farming depended on collecting storm water run-off in small catchment areas (approximately 100 sq. metres) and using it to irrigate trees planted in the lowest part of the micro-catchment area.

Most soils on the Ngaanyatjarra, Pitjantjatjara and Yankunytjatjara lands are porous and soak up storm water quickly rather than collecting it as surface water. Hence the micro-catchment system used in Israel was only partially successful, when used on these soils.

During Mike's visit to Warburton, heavy rain prevented himself and his family from returning to Ernabella. While waiting for the roads to open, he observed the capacity of the soil to collect storm water. It had a high clay content and yet remained friable. The potential for this soil type to collect storm water was very encouraging and this location would be an excellent site for further trials.

In his role as Land Management Adviser for Pitjantjatjara Council, Mike worked across all the Ngaanyatjarra, Pitjantjatjara and Yankunytjatjara lands, including Warburton. Toward the end of the 1980's the adviser at Warburton, Mr Damien McLean talked to Mike about the community's concerns re-the local flooding being experienced within the community.

In the 1940's much of the mulga (acacia aneura) had been cut down to produce charcoal to fuel the trucks which brought supplies into the area. This reduction in trees, exposed the soil surface, resulting in the dry, surface vegetation being blown away and losing the environment in which to germinate new plants. The cattle around the community compounded the problem by eating the small amount of vegetation which grew after rain. Generally people had a concern for the degraded land that surrounded them.

A levee bank was built around the housing area which diverted the storm water but didn't prevent the cause of it. The cattle were sold off allowing the area to revegetate again.

The problems that remained were to:

1. Reduce the local flooding.
2. Revegetate the area.

An old disused airstrip which extended for several kilometres from the community toward the Warburton range to the east, collected much of the water which flowed into the town area and caused the flooding. A drain had been cut across the airstrip, however the catchment was too large for one drain to manage the resultant storm water. Damien asked Mike what could be done to solve the local flooding problem and begin a revegetation program. The experience of the Land Conservation Unit in Alice Springs was called upon once again. Mr Rob Keetch was able to visit Warburton with Mike and make a plan to build ponding banks for the first square kilometre to the east of the community.

The ponding banks were sown with grass and tree seeds and collected storm water to assist the germination and growth of this vegetation. Previously the area was covered with trees, around which accumulated a mulch of dried vegetable material which helped trap storm water, resulting in the germination and growth of trees, shrubs and grasses. Without the trees and shrubs the mulch and seed blew away and the soil surface became bare and hard, shedding storm water rapidly. This water accumulated and caused local flooding. The ponding banks acted in the same way as the trees and shrubs did ie. to collect airborne seed, dry vegetable material for mulch, and storm water. This provided an environment which sustained the revegetation process.

The project was managed over a two year period with funding being made available from the National Soil Conservation Program. The Land Conservation unit agreed to provide equipment, seed and personnel, while the Warburton community provided a grader, fuel and accommodation.

Stage 1 - (February 91)

In February 1991, one week was set aside for the construction of ponding banks, spirals and staggered furrows by Land Conservation staff. Fourteen ponding banks were constructed on the eastern side of the community. Staggered furrows and spirals were ploughed on approximately two hundred hectares around the community. Above average rains (250 mm) were received within three months of completing the work.

The following sections demonstrate the techniques and results gained from building ponding banks. Spirals and staggered furrows were also used to assist the revegetation process:

Stage I - Constructing Ponding Banks (February 91)
Stage I - Staggered Furrows and Spirals (February 91)
Stage I - Storm Water Collection (June 91)
Stage I - Revegetation Results (February 92)

Stage 2 - (February 92)

The result of heavy rains on stage I of the project, precipitated the need to add more ponding banks, build a diversion bank, and plough more staggered furrows to assist the revegetation process and further reduce the risk of local flooding. The revegetation which resulted from stage I, provided encouragement, hence the Land Conservation Unit agreed to bring their equipment for stage II. On this occasion the community provided equipment, fuel and accommodation again and Pitjantjatjara Council Land Management brought their new tractor and opposed disc plough. Land Conservation staff were able to train Pitjantjatjara Council staff in the used of equipment for direct seeding work.

The following pictures demonstrate the techniques and results gained from building a diversion bank, re-seeding ponding banks constructed in Stage I and constructing more staggered furrows.

Stage II - Diversion Bank (February 92)
Stage II - Staggered Furrows (February 92)
Stage II - Revegetation Results

Concluding Comments

The magnitude of the land degradation problems in this project were large and the results demonstrate that solutions are possible and the environment can be repaired. Land degradation usually occurs over many years and hence many years are often needed to repair the damage. Rainfall in the arid zone is not very dependable, however it came at the right time for this work. It wasn't possible to record all information relating to the project nor was it possible to record all the results eg. rainfall, however it was possible to keep a photographic record. Hence, if further information is required about this project, please use the contact details provided.

Plant List

Seed of the following plants were direct seeded in stages I and II.