Hydrology and Hydrological Assessments
Hydrological Assessment | Hydrology Assessment by Waterco Consultants
Hydrology is the study of processes of the water cycle such as evaporation, evapotranspiration, rainfall, runoff, infiltration and storage of water.
In engineering, a hydrological assessment is carried out to quantify the flow or volume of water in a river or stream, over land, in soils, in a pond or in a reservoir. This is used to assess the pluvial, fluvial or groundwater flood risk to a site or to evaluate the capacity of a soakaway, storage pond, reservoir or culvert.
Understanding the potential impact of flood water on a site is crucial to any developer looking to invest in a building scheme or any planner, engineer or architect acting as adviser to such development. In addition, changes to the way rural land is used, coupled with deforestation, changes to the density of animal stock, diversification and winter crop cycles, can all influence water flow and can increase the risk of flooding.
Hydrological assessment is therefore used to help reassure or alert developers, planners and land managers to potential issues for concern.
It is difficult to accurately predict how any one development or individual land use change might affect the likelihood of flooding, but finding holistic strategies to reduce and control water flows while maintaining production and reducing soil loss, are at the heart of modern land management.
Waterco’s expertise in this area includes:
- catchment and watershed analysis
- flow estimation
- flood event analysis
- rainfall run-off modelling
- overland flow/surface water management
- culvert capacity analysis
- hydrology for change in land use
- water resources hydrology
In addition Waterco can offer advice on such things as:
- reducing silting, rilling and soil loss
- breach modelling - see also hydraulic modelling
- car park positioning and debris flow damage
- advice on afforestation and deforestation
- new roadway catchment diversions
- hydrological investigations of wetlands
Waterco has working relationships with the approved bodies including the Environment Agency (EA), Natural Resources Wales (NRW) and the Scottish Environment Protection Agency (SEPA). Our Hydrologists have an excellent understanding of the methods outlined in the Flood Estimation Handbook (FEH) - the industry standard accepted by the approved bodies - and uses the FEH Web Service and related flood estimation software such as WINFAP FEH 3 and ReFH.
Flood hydrology analyses how flooding happens – i.e. how a catchment responds to a recent rainfall event.
Local Authorities are under pressure as the frequency and intensity of flooding increases and, with mean winter rainfall predicted to increase, the effect on already waterlogged areas will be significant. Home and business owners who have experienced flooding want to know the probability of such a flood recurring.
Estimating the increase in surface water in any catchment area involves:
- rainfall event analysis
- fluvial flood analysis
- surface water flood analysis
- tidal flooding event analysis
- hydrographs and peak flows for inputs into hydraulic models
- estimation of flood hydrographs in man-made and altered catchments including urban and permeable catchments
- flood investigation reports
- reservoir flooding
- the implications of climate change on flooding.