Instream Structure Prioritisation (Protected areas)

The objective of this method is to assist those undertaking inventories of instream structures that impact on fish habitats, wetland condition and movement of fish and other aquatic species in declared Fish Habitat Areas and Ramsar sites. This method scores and prioritises structures and provides a Response Action Plan (RAP) that includes a list of priority structures and identifies management actions for every type of structure.

This method implements a framework and guidelines developed by Fisheries Queensland (Targeted collection of inventory data for wetlands fish barriers in the Great Barrier Reef catchment ), and the former Department of National Parks, Sport and Racing (NPRSR) (Guidelines for conducting an inventory of instream structures in coastal Queensland) (The Guidelines).

This method employs the framework and guidelines above to develop inventories of instream structures including fish passage, and identify priority structures impacting on wetland condition and fish habitats in declared Fish Habitat Areas and Ramsar wetlands.

The baseline information, together with guidance on prioritising which instream structures to remediate, assists with decision making when assessing future development impacts on Ramsar sites and adjacent areas, including coastal declared fish habitat areas.

Barriers to fish passage such as dams, weirs, causeways, culverts, earthen bunds and floodgates can impact the health of aquatic systems by altering natural flow regimes, and causing impassable barriers to aquatic fauna, especially fish. Many high value fish species require unimpeded access between habitats (i.e. between inland freshwater habitats and estuarine/marine habitats).

Instream structures such as jetties, pontoons, boat ramps and revetments can impact fish habitats by causing physical disturbances that result in direct habitat loss or fragmentation.

Urban development and the modification of natural wetland systems present potential threats to the ecological character of Ramsar wetlands from linear infrastructure without appropriate culverts, which can interrupt natural surface water and groundwater flow paths.

By identifying and assessing the impacts of instream structures on Ramsar wetlands and recording wetlands inventory information, structure inventory project data supplements the Ecological Character Description and forms a baseline against which to measure future impacts.

The first stage in the process is the inventory protocol for instream structure identification via a desktop assessment using GIS data and existing approvals information (fisheries development approvals, boat ramps, prescribed tidal works).

Structure types in this method included barriers (physical and large barriers such as bridges, culverts and causeways) and non-barriers such as pile supported structures (jetties, pontoons), rubbish/wreckage, stabilisation structures (revetments and groynes) and fill and slab structures (boat ramps, houses, wharves).

Aerial surveys, boat-based surveys and ground surveys are conducted of each project area to confirm identification of barriers and non-barriers. Field assessments are conducted where possible at low tide. Consultation with working groups also is conducted.

The second stage of the method is a Response Protocol to identify management priorities by scoring the instream structures.

The criteria scores are assigned a position in a prioritisation matrix based on habitat value and fish-friendly scores. The four matrix quarters are:

• Less fish-friendly structures in high value habitat
• Less fish-friendly structures in low value habitat
• More fish-friendly structures in low value habitat
• More fish-friendly structures in high value habitat

Part 1: Remote risk assessment:

Structure identification using GIS:

• Watercourses
• Vegetation
• Infrastructure
• Waterholes
• Bores
• Land tenure
• Existing approval information

Structure identification using field collection:

• General information
• Spatial location
• Site details
• Non-barrier type
• Barrier type
• Barrier details
• Fish passage details
• Habitat
• Vegetation
• Threats/impacts
• Location
• Ownership

Part 2 Risk assessment/scoring of structures:

• Habitat value criteria
• Habitat class
• Extra fisheries value
• Habitat condition
• Relation to declared Fish Habitat Areas

Fish friendly criteria for barriers:

• Barrier type
• Barrier impact

Fish friendly criteria for non-barriers:

• Structure type
• Disturbance area

• Physical and spatial data fobarrier and non-barriers (i.e. bridges, culverts, road crossings, infrastructure), including disturbance area
• Barrier characteristics in relation to fish passage (i.e. culvert level)
• Non-barrier characteristics in relation to physical impacts on fish habitats and disturbance area
• Water infrastructure information (i.e. bores, ownership)
• Tenure information
• Development approvals in and adjacent to study area
• High quality imagery
• Wetland mapping (wetland area)
• Barrier  and non-barrier types
• Habitat condition
• Fish species information (habitat requirements, economic (fisheries) significance)

Expert knowledge of aquatic fauna ecology including habitat requirements and fisheries value. Field assessment skills and GIS data analysis skills. Knowledge of fisheries in the study area and current development activities.

• Geographic Information System for structure identification.
• High quality imagery (satellite/drone)
• Mobile data collection device (e.g. Personal Digital Assistant (PDA))
• Boats and associated equipment
• Cameras

Inventory Protocol and Field Assessment/Structure Identification:
All potential barriers and non-barriers in the study area are identified and an inventory is produced. A list of relevant fisheries development approvals in and adjacent to study area. Aerial, boat and ground surveys together with field assessments inputs further refine list of potential barriers and non-barriers.

Response Protocol (prioritising of structures):
Structures from the list from Inventory Protocol and Field Assessment/Structure Identification scored and placed into the prioritisation matrix. A list of highest priority structures in accordance with a structure's position in the matrix (Quarter 1 - highest priority).

Response Action Plan:
A Response Action Plan (RAP) which identifies the priority structures and contains recommended management actions for the study area.

• Can be used as an input t prioritise remedial actions for barriers to fish passage non-barriers impacting on fish habitats used by region Natural Resource Management (NRM) groups, local catchment groups and government.
• Input into development of investment strategies for fish barrie non-barrier remediation works.
• Input into decisions regarding fisheries development approvals adjacent to, and in, Ramsar sites.
• Threat and risk identification.
• Decision support.
• Inform priorities of management interventions required to reduce risks to ecosystems from different threats and improve ecosystem condition.

Designed for federal, state or local government agencies, catchment management groups and NRM groups.

• Comprehensive instream structure identification for large physical structures and other structures that impede fish passage that are not normally recognised (i.e. rubbish build up)
• Sound method from GIS desktop analysis to field truthing for identifying structures
• Provides many comprehensive recommendations for barrier and non-barrier management
• Recommendations focus on fish life cycles and behaviour
• Provides a measure of current development pressures which is included in the inventory of structure
• Provides a baseline of existing infrastructure useful to assess future development impact
• Prioritise barriers and non-barriers for management

• Not whole of catchment scale – focussed on study areas which have been based on Ramsar sites and declared fish habitat areas
• Largely developed for application in tidal areas and lower catchment
• Does not undertake a socioeconomic assessment or assessment of economic viability of recommendations

Enhanced management of Ramsar site wetlands within the Great Sandy Strait catchments site wetlands within the Great Enhanced management of Ramsar site wetlands within the Great Sandy Strait catchments

Inventory of Instream Structures Impacting on Ramsar Wetlands

Targeted collection of inventory data for wetlands fish barriers of the Great Barrier Reef catchment fish barriers of the Great Barrier Reef catchment

This page should be cited as:

Department of Environment, Science and Innovation, Queensland (2021) Instream Structure Prioritisation (Protected areas), WetlandInfo website, accessed 18 March 2024. Available at: https://wetlandinfo.des.qld.gov.au/wetlands/resources/tools/assessment-search-tool/instream-structure-prioritisation-protected-areas/