Dataset: Namoi ZoPHC and component layers 20170629


Description

Abstract

This dataset was derived by the Bioregional Assessment Programme from multiple source datasets. The source datasets are identified in the Lineage field in this metadata statement. The processes undertaken to produce this derived dataset are described in the History field in this metadata statement.

Dataset contains assessment units with attributes denoting their inclusion within surface water and groundwater zones potential hydrological change, groundwater mine footprints, reporting regions, and surface water model interpolation allocations. Dataset also contains the river lines containing surface water modelling reaches and a relational table of surface water modelling node to reach ID interpolations.

Dataset History

Namoi assessment units (AUs) copied out to form basis of zone master geometry.

GW zone defined from dmax to AU relational table (where 95th acrd >= 0.2 m).

AUs intersected with GW zone - gw_zophc field = 'yes', otherwise 'no'.

Modelled reaches linework by splitting up RiverStyles by reachID (from Neil's table/diagram), creation of csv look up table (relating reachID to interpolated node).

Additional stream network from Geofab clipped to PAE/subregion.

1 km buffer applied to lower lying streams based on expert judgement of topography and hydrologic connection.

AUs intersected with buffered streams, further editing to include hydrologically connected landscape class features (LCs) using Geofab as a guide:

LC_Class = 'Floodplain riparian forest' OR LC_Class = 'Floodplain riparian forest GDE' OR LC_Class = 'Floodplain wetland' OR LC_Class = 'Floodplain wetland GDE' OR LC_Class = 'Upland riparian forest GDE' OR LC_Class = 'Permanent lowland stream' OR LC_Class = 'Permanent lowland stream GDE'

Permanent upland stream GDE, Temporary upland stream GDE, Permanent upland stream, Temporary upland stream, Permanent lowland stream GDE, Temporary lowland stream GDE, Permanent lowland stream, Temporary lowland stream.

AUs intersected with GW mine footprints for open cut mines only for all futures, mine_pit field = 'yes' otherwise 'no', where yes applies to exclusion areas for groundwater HRVs (crx/cri) and summaries of mine pit areas alone (crm).

AUs intersecting modelled reaches given: sw_zophc = 'yes', alloc_rule = 'Intersecting SW reach - mod_ch', SW_model = 'yes', allocreach = ReachID 'rch_xxx'.

AUs related to modelled reaches but not intersecting reaches given: sw_zophc = 'yes', alloc_rule = 'Nearest SW reach - mod_ch', SW_model = 'yes', allocreach = ReachID 'rch_xxx'.

AUs related to streams not modelled but potentially impacted through hydrological changes upstream either through connection with impacted reaches or with headwaters of permanent streams within the groundwater zone given: sw_zophc = 'yes', alloc_rule = 'Nearest SW reach - ass_chph', SW_model = 'no', allocreach = 'rch_200'.

AUs intersecting and downstream following streams not modelled, of surface water mine footprints (but only for acrd and crdp futures) given: sw_zophc = 'yes', alloc_rule = 'Nearest SW reach - ass_chpx', SW_model = 'no', allocreach = 'rch_300'.

Stream (reach) to AU relationships are 1:1 and were governed by a hierarchical rule set where >1 reach intersected an AU:

  1. Modelled change

  2. Assumed change

  3. Modelled no change

  4. Assumed no change

Further tie-breaks were decide based on stream order or stream segment length.

Three reporting regions ('Basin' field) were initially defined, lower, mid and upper Namoi; these were assigned through expert judgment following assessment and logical grouping of hydrologically connected areas: Basin = 'Lower Namoi' or 'Mid Namoi' or 'Upper Namoi'.

AUs outside (not intersecting) the PAE/AE in north-western corner of the combined zone (total of 79 from the surface water zone) and outside subregion boundary (total of 8 from the groundwater zone) along western edge of the combined zone were re-assigned to outside of combined zone.

An additional reporting region was created to represent the Pilliga and Pilliga Outwash areas (Pilliga) based on IBRA subregion boundaries with the Namoi Alluvium polygon clipped out. GW/SW zone AUs with their centroids within the Pilliga zone were selected and assigned to Pilliga and outwash (Basin = 'Pilliga and outwash'). Some manual editing of AUs near the boundary of the Pilliga area was performed to include or exclude AUs based on their regional hydrological relationships e.g. with main channel.

Output data:

NAM_ZoPHC_AU_Master_20170629.shp - Assessment units with zone attributes and allocated reach IDs.

NamoiRiverStylesReachID_20170601.shp - River line-work split by reaches and assigned Reach IDs based on surface water model interpolations.

NAM_Interpolation_20170601.csv - Lookup table relating node IDs to Reach IDs.

Dataset Citation

Bioregional Assessment Programme (2017) Namoi ZoPHC and component layers 20170629. Bioregional Assessment Derived Dataset. Viewed 11 December 2018, http://data.bioregionalassessments.gov.au/dataset/170e608f-da0d-4fce-889c-cdd0ab137cea.

Dataset Ancestors

General Information

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