Table 4.4 Salinity risk assessments for hydrozones (numbers in parentheses relate to hydrozone numbers in Figure 4.1) % of zone % of zone within Land within Hydrozone Monitor A O Land Dominant Likelihood Consequence Timing of name & C L P in Monitor A groundwater of future of future future Salinity number 1996–98 H A V F trend salinity salinity salinity risk Comments Kalbarri Less than 1 the Land variable possible moderate medium moderate Variable groundwater trends occur Sandplain (1) Monitor term throughout this hydrozone. Rising mapping trends occur where groundwater is product less than 15m deep. Falling and did not stable trends occur where produce a groundwater is deep (more than reliable 15m). The salinity risk is moderate estimate because of the extensive areas of for this flat plains. hydrozone Northampton the Land 17 mostly rising unlikely minor short low Prior to 2000, this hydrozone Block (2) Monitor appeared to be in hydrological mapping equilibrium. In 2001–07, drought product did led to significant groundwater not produce decline. Since 2007, groundwater a reliable levels have been rising but estimate for generally remain below pre-2000 this levels. Salinity is unlikely to hydrozone expand, the consequences will be minor because the incised topography would restrict the extent. Rising groundwater trends East Binnu less than 1 the Land mostly rising almost moderate medium high dominate. Consistent rising Sandplain (3) Monitor certain term groundwater and extensive areas mapping where groundwater is less than product 10m deep make it almost certain did not
Table 4.4 Salinity risk assessments for hydrozones (numbers in parentheses relate to hydrozone numbers in Figure 4.1) Hydrozone name & number % of zone within Land Monitor A O C L P in 1996–98 % of zone within Land Monitor A H A V F Dominant groundwater trend Likelihood of future salinity Consequence of future salinity Timing of future salinity Salinity risk Comments Kalbarri Sandplain (1) Less than 1 the Land Monitor mapping product did not produce a reliable estimate for this hydrozone variable possible moderate medium term moderate Variable groundwater trends occur throughout this hydrozone. Rising trends occur where groundwater is less than 15m deep. Falling and stable trends occur where groundwater is deep (more than 15m). The salinity risk is moderate because of the extensive areas of flat plains. Northampton Block (2) the Land Monitor mapping product did not produce a reliable estimate for this hydrozone 17 mostly rising unlikely minor short low Prior to 2000, this hydrozone appeared to be in hydrological equilibrium. In 2001–07, drought led to significant groundwater decline. Since 2007, groundwater levels have been rising but generally remain below pre-2000 levels. Salinity is unlikely to expand, the consequences will be minor because the incised topography would restrict the extent. East Binnu Sandplain (3) less than 1 the Land Monitor mapping product did not mostly rising almost certain moderate medium term high Rising groundwater trends dominate. Consistent rising groundwater and extensive areas where groundwater is less than 10m deep make it almost certain
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