MAP Rain – New FEH 2013 Rainfall Return Period calculator

FEH is the industry standard used to estimate local flood risk and develop resilient infrastructure.

New Service – Rainfall Return Period calculation for any location using the FEH 2013 methodology

MAP Rain dashboard and rainfall map now includes the updated FEH (Flood Estimation Handbook) 2013 methodology as well as the original FEH99 method. This provides the Return Period calculation for any location and any date in the past 4 years using the MAP Rain dashboard. These Return Period calculations are available for both Points and Polygons.

You can use the MAP Rain dashboard to calculate:

The depth (mm) and duration (hours) of rainfall that generates the largest Return Period on a particular day

The depth (mm) of rain for the location that generates a specific Return Period for a specific rainfall duration (hours)

For more information on our MAP Rain dashboard and rainfall map click here

Predicted Rainfall Alerts
MAP Rain can also apply the FEH 2013 methodology to the forecast rainfall so that we can send you e-mail alerts for any significant rain events that may impact flooding hotspots.

Return Period calculation API calls

We have built two API calls into MAP to let you integrate the FEH 2013 return period calculations directly into your own applications. Please note that these call will take about 2 minutes to return.

Returns depth (mm), duration (hours) and Return Period for a particular day and location

Inputs

Date 17th Sept 2017 (rainy day)
Location in Long Lat (WGS84) or OS Easting and Northing

Returns

Rain Event Start and End Time 14:30 to 16:00
Duration 1.5 hours
Max Depth 16.68 mm
Return Period 1 in 2.45 years

Returns depth of rain (mm) for a specific duration (hours), return period and location

Inputs

Location in Long Lat (WGS84) or OS Easting and Northing
Duration 5 hours
Return Period 1 in 20 years

Returns
Max Depth 47.72 mm

Acknowledgement

FEH Return Periods calculated by Meniscus through use of FEH1999 and FEH2013 DDF model © and Database right NERC (CEH).

Stewart, E. J.; Jones, D. A.; Svensson, C.; Morris, D. G.; Dempsey, P.; Dent, J. E.; Collier, C. G.; Anderson, C. A.. 2013 Reservoir Safety – Long Return Period Rainfall. Project FD2613 WS 194/2/39 Technical Report (two volumes). Joint Defra/Environment Agency Flood and Coastal Erosion Risk Management R&D Programme.