Mitigating Overland Flooding Risks Through Proactive Surveying

"We are an all-inclusive shop for land development requirements”

Flood risks are an unfortunate reality for many properties, especially here in Queensland. When heavy rains overwhelm rivers and stormwater systems, floodwaters can cause substantial damage. As climate change brings more extreme weather events, flooding may worsen. 

Understandably, councils have regulations about building and renovating in designated flood zones. Determining those zones requires detailed mapping and modelling of historic flood levels, drainage patterns and projected risks. This is where flood level surveys come in.

Our specialty at Site Surveys is providing accurate and up-to-date flood risk analysis to inform major planning and construction decisions. Detailed flood studies underpin development approvals, building code requirements, infrastructure investments, and disaster preparedness. We use advanced surveying, 3D terrain mapping and hydrological modelling to establish authoritative flood level data.

For property buyers and owners, our flood risk assessments take the guesswork out of evaluating a site’s true flood exposure. We can verify previous flood heights and objectively gauge the likelihood of future inundation. This gives insurers and lenders confidence when underwriting assets, and arms residents with information to make smart decisions in floodplain locales.

In a field often marked by trauma and frustration, Site Surveys aims to bring clarity and enable prudent planning. We recognize that quality flood data empowers communities to coexist safely alongside local waterways, even as risks evolve.

Establishing Flood Levels

Accurately determining historic flood levels is crucial for modeling future risks. We thoroughly research local records, news reports and imagery to identify peak flood heights and extents. Interviews with long-term residents also provide valuable on-the-ground perspectives.

Our survey teams then map creek channels, drainage infrastructure, terrain and vegetation in high-resolution detail across floodplains. Precise contour surveying captures subtle elevation changes that influence water flows. We process these terrain models to reconstruct historic events and run hydrological simulations to predict flooding patterns.

This mapping delineates official floodplains, channels stormwater systems and quantifies drainage capacities. It also reveals flood flow paths and local catchment boundaries. By linking this terrain data to rainfall records and flood probability analysis, we generate hazard mapping for floods ranging from 1-in-10 year events to extreme 1-in-500 year scenarios under projected climate change influences.

Our flood modelling approach aligns with industry best practices and government guidelines. We choose state-of-the-art tools tailored for each situation, whether 2D overland flow, 1D stormwater modelling, or complex combined flood and storm tide analysis. This advanced modelling capability allows us to handle the most challenging flood behaviour, like swiftly flowing creeks bursting banks or slow drainage flooding low-lying zones.

Identifying Flood Risk Zones

The flood modelling process delineates areas exposed to varying degrees of hazard during different magnitude flood events. We classify risk zones based on modelled flood depths and velocities, aligned to government guidelines.

Zones indicate flood probability – for example the 1-in-100 year floodplain may be deemed high hazard. We also factor in potential flood emergency response, distinguishing zones where timely evacuation would be difficult. Climate change projections may necessitate even larger allowances in some coastal areas.

This zonation informs land use planning and development controls under floodplain management plans. It sets ground and floor heights to avoid inundation. Higher hazard zones carry more stringent building requirements. We provide the authoritative flood data that councils require to implement these plans.

Key Applications of Flood Data

Flood information has wide-ranging applications for improving community safety, guiding growth and building resilience. Precise flood levels drive approvals for subdivision works and new construction. Building certifiers reference our reports to enforce flood-aware designs under development codes.

Urban designers use our studies to site landforms that divert floods without displacement. Flood data also helps size culverts, levees, detention basins and seawalls to handle flood volumes. For existing assets like bridges and pipelines, it provides load cases for structural review.

Emergency managers utilise our flood intelligence for disaster preparation and response. Flood extent, depth and hazard mapping enables effective planning of evacuations, supply chains and recovery efforts. Real-time flood sensors can also activate alerts based on thresholds from our analysis.

Insurance providers consult our assessments to price assets reflectively – rewarding properties built to withstand floods. For prospective residents, we clarify actual risks before financial commitments, bringing peace of mind.

Using Surveys for Flood Risk Management

Regular surveying is key to responsible floodplain management. We resample watercourse dimensions and sediment buildup to maintain accurate hydraulic models. Monitoring also helps councils schedule dredging and vegetation clearing to preserve drainage capacity.

Likewise, our teams resurvey infrastructure condition and functionality before flood season. We identify under-capacity stormwater drains or degraded levee banks needing repair. This prevents failures that would exacerbate flooding.

Upgrading flood mitigation infrastructure requires robust hydrological analysis – our specialty. We optimise detention basin sizing and outlet configurations to attenuate stormwater peaks. For levees and floodgates, we provide overtopping scenarios, seepage estimates and structural loading data.

Advising Property Buyers

When purchasing property, flood risk clarity brings peace of mind. We objectively assess individual sites based on modelled flood levels across a range of annual exceedance probabilities.

Our flood certificates verify previous flood heights and localise depth maps. We outline site attributes that mitigate or concentrate flood impacts. This allows buyers to price risks into negotiations and plan adaptive measures.

Reporting also supports insurance underwriting. We substantiate that homes meet freeboard requirements or qualify for premium discounts. Alternatively, identified deficiencies may preclude coverage entirely. Either way, buyers enter ownership aware of where they stand.

For waterfront or low-lying buildings, we recommend flood-resilient construction and adaptive features like raised floor levels. Our guidance aligns with council codes so owners can renovate with confidence. We aim to educate households to coexist safely with flood hazards.


Detailed flood analysis is integral to building community resilience against rising flood exposure. As demonstrated, flood level surveys have diverse applications from shaping disaster response to enabling climate-aware development.

Through high-precision contour mapping and advanced hydrological modelling, our flood studies quantify risks for present and future climate scenarios. This predictive intelligence guides infrastructure investments, zoning decisions and construction standards that mitigate dangers.

For councils, our floodplain analysis provides authoritative hazard data to progress floodplain management plans. For developers, we facilitate approvals by aligning designs to flood standards early on. For property buyers, we illuminate risks before financial outlays are made.

Yet floods will still occur, testing defences. Here our real-time monitoring and asset reviews help emergency planners and infrastructure custodians. We believe holistic flood data minimises harm when floods eventually overtop.

Ultimately Site Surveys aims to promote informed, shared responsibility for flood resilience. Working cooperatively with climatic realities, not fighting blindly against waterways, leads to safer, more sustainable communities. Our flood services provide the impartial technical base for navigating those decisions.

Need Help? Let’s Get in Touch

Our Address

425 Maroondah Hwy, Croydon North VIC 3136

Have a Question? Feel Free To Contact Us.

Got a query related to land development for your Melbourne property, or want the advice of a private land surveyor based in Melbourne? For more information about our land  surveying services in Victoria, contact Stacey Surveying today by calling 03 9088 3695 or completing our convenient online contact form.

    question-imageWe are Unable to Quote Without The Full Property Address