Adjustment to Salinity in Irrigation Regions: Ex Post Evaluation of the Tragowel Plains Plan

An early-mid project evaluation of the benefits and costs of the Tragowel Plains Salinity Management Plan estimated the net cost after six years at A$ 5.5 million. The cumulative cash flows for the water transfer, drainage and halophyte programs were all positive with benefit to cost ratios (BCRs) of 3.2, 1.3 and 1.1. Inclusion of estimated future benefits and costs to year 30 gave BCRs of 13.7, 1.3 and 4.0 with net present values (NPVs) of A$ 18.8 million, 2.5 million and 0.4 million respectively. Net costs for other integrated programs including salinity survey, whole farm planning, facilitation of structural adjustment, revegetation and coordination of implementation reduced the NPV of the first six years of implementation to A$ 12.1 million. The water transfer program NPV was comparable to the market value for water right over the period. Only a small proportion of water right was transferred to land outside the plan area, indicating that the Tragowel Plains remained competitive for resources.