HYDROLOGY, RIVERS & FLOODING

We analyse catchments to determine anticipated flood flows, and model flows to determine how they interact with the natural and built environment. The services we offer include:

• Assessment of catchment hydrology to inform potential clearwater flooding & debris flood flows using NZ flood estimation resources appropriate to the catchment type and modelling tools where required (such as HEC-HMS, HEC-RAS rain on grid)

• 2D flood modelling using HEC-RAS and high-resolution LiDAR digital elevation models in conjunction with proposed earthworks, development plans and/or site surveys as required.

• Design of river erosion protection and flood mitigation works

• Minimum floor level recommendations for buildings for alluvial flooding or overland flow

• Assessment of alluvial fan flood hazard along with risk assessment for development including avoidance or mitigation strategies