Property of RL (Ray) and NT Gunn, Tammin, Western Australia, Australia - 009

Surveyors Report on WISALTS Conservation System created by B (Ben) Davey.

Comments: This is a rough draft of the preferred option for this site. Extensive testing has to be done before deciding if it is the most viable option. Basically the laterite based hill slope is shedding onto salmon gum soils which continue to shed water through the town, plus onto the flat which has from 4 inches to 14 inches of sandy loam over clay, consequently it suffers from severe waterlogging. Throughflows are feeding from several directions causing the flat to collapse.

Review Comments: In consideration of the fact that most of the catchment above the level bank constructed to the dam has been treated with a level bank system, I would consider the bank to be adequate. Though if the catchment hadn't been treated I would have had the bank constructed to twice the width for more capacity. The section of bank constructed by the 25 could have been deeper only being constructed to 85 centimetres. One clay section just next to the dam should of have had 2 more rips for the second push. This would have broken the compacted clay up more making it less likely for the water to leak between the large lumps of soil. 50 metres from the dam end of the bank is a section of (60 metres) red and white mottled sandy material which does concern me. I question the wisdom of trying to seal the dam with the plastic. Also there is no provision for overflows, plus there is another throughflow leaking through the bank on the north side of the dam. In my opinion a better option would have been to pick up the overflow where these areas join with a grade line sealed with plastic cutting all off in one hit.

This document is part of the WISALTS (Whittington Interceptor Sustainable Agriculture Land Treatment Society Incorporated) Collection.