Cumulative Impact Model
The Cumulative Impact Model (CIM) examines how the $89.9 Billion major project pipeline may drive future workforce growth, population change, housing demand, infrastructure requirements, and community service needs within the City of Karratha.
The Cumulative Impact Model
The Cumulative Impact Model (CIM) provides a structured framework for understanding how major projects (Stage 1) drive workforce and population growth (Stage 2), which in turn increase demand for housing, infrastructure, and essential services within the City (Stage 3).
GROWTH SCENARIOS
DRIVES WORKFORCE AND POPULATION GROWTH
WHICH LEADS TO DEMAND FOR ADDITIONAL HOUSING, ACCOMMODATION AND SERVICES
GROWTH SCENARIOS
DRIVES WORKFORCE AND POPULATION GROWTH
WHICH LEADS TO DEMAND FOR ADDITIONAL HOUSING, ACCOMMODATION AND SERVICES
Stage 1: Major Project Pipeline Growth Scenarios
The City has a project pipeline of $89.9 Billion, ranging from early stage concepts to shovel-ready projects, located within and surrounding the City of Karratha Local Government Area. The project pipeline is based on information available as of June 2026, and subsequent changes to project scope, timing, value, or status are not reflected in the model.
In addition to the baseline, two growth scenarios were developed to reflect different levels of project delivery, infrastructure availability, and certainty within the major project pipeline.
Baseline
The Baseline scenario reflects the continuation of long-term population and economic growth trends under current market conditions and infrastructure capacity. Historically, growth within the Karratha region has been highly cyclical, with periods of rapid expansion driven by major projects followed by periods of slower growth as project activity declines. The Baseline scenario captures the region's longer-term growth trajectory by drawing on trends that incorporate both boom and downturn periods, rather than reflecting any single project cycle.
Throughout the CIM, baseline demand refers to the workforce, population, housing, utilities and service demand generated by this continuation of established growth trends. The Green-lit and All Projects scenarios represent additional growth above this long-term trend by incorporating the impacts of future major developments. As a result, they illustrate periods of accelerated growth that are more comparable to the elevated growth experienced during previous resource and infrastructure booms.
Green-lit Projects
The Green-lit Projects scenario represents approximately $28.8 Billion in approved, funded, or development ready projects. These are mostly under construction or committed projects with a high likelihood of proceeding. For modelling purposes, projects are weighted based on project readiness and their relative likelihood of proceeding, resulting in a weighted project value of approximately $27.2 Billion. This scenario reflects the level of growth expected to occur and highlights the known demand for housing, accommodation, utilities and services that need to be delivered to support these already committed projects.
All Projects
The All Projects scenario represents the broader $89.9 Billion project pipeline, including projects at earlier stages of development, as well as all projects within Green-lit Projects. For modelling purposes, projects are weighted based on their relative likelihood of proceeding, resulting in a weighted project value of approximately $55.2 Billion.
Stage 2: Workforce and Population Growth
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The City currently has a very low unemployment rate. Delivery of projects under the Green-lit Projects and All Projects scenarios will therefore require a significant additional external workforce comprising both residential and FIFO workers, reflecting limited spare capacity within the local labour market to meet projected labour demand.
The figure below illustrates the projected workforce required under each growth scenario.
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Under the Baseline scenario, the City's population is projected to continue growing at its long-term rate through births, deaths, and migration.
Under the Green-lit and All Projects scenarios, additional residential workers and their families are expected to relocate to the City.
FIFO workers are not captured in the resident population shown in the figure below. However, they will still create demand for short-stay accommodation, services and utilities within the City, as a non-residential population temporarily residing in the city and contributing to accommodation and service requirements.
The figure below illustrates the projected population under each growth scenario.
Stage 3: Housing and Services Demand
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Under the Baseline scenario, housing demand is projected to grow in line with existing market trends and serviced land availability. The City currently has limited housing stock available for sale or rent within the general market.
Under the Green-lit and All Projects scenarios, additional residential workers and their families relocating to the City are expected to significantly increase demand for new private dwellings.
The figures below illustrate projected additional dwelling demand and housing supply required under each growth scenario.
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Additional workforce and population growth under the Green-lit and All Projects scenarios is expected to increase demand for health, education, emergency, and community safety professionals within the City.
The model estimates service demand generated by population and workforce growth under each scenario. The existing relative undersupply in several service areas under the Baseline scenario is a broader service provision context and is not closed by, or included in, the additional project demand shown in the figures below.
The figures below illustrate the projected number of additional health, education, emergency, and community safety professionals required under each growth scenario.
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The Green-lit and All Projects scenarios demonstrate the significant economic opportunity associated with continued project delivery within the City.
Without sufficient housing, accommodation, infrastructure, utilities, and essential services to maintain a high level of liveability, major projects may be delayed, scaled back, or unable to proceed. This would reduce employment growth, economic output, and value-added across the regional economy.
The figure below illustrates the estimated economic opportunity cost associated with constrained project delivery resulting from housing, accommodation, infrastructure, and service shortfalls under the Green-lit and All Projects scenarios by 2046.
Employment (Jobs)
Output
Value-Added
The model only quantifies the economic impacts associated with constrained project delivery. It does not capture broader opportunity costs such as lower revenue to all levels of government, including reduced Council rates revenue, lower State royalty revenue, and lower Commonwealth GST and income tax revenue.