Hydrology

Hydrology

Analysis of precipitation events and surface run-off had been the subject of speculation for ages. As of the second half of the 18th century the concept of the time of concentration – today the backbone of the rational method - was first described; since then significant advances have been made in quantifying the precipitation volume and establishing the surface water motion.

Hydrology greatly relies on the analysis of statistical data; several methodologies have been developed correlating flow measurements with recorded precipitation events in various watersheds around the globe. Based on the size, location and geomorphological characteristics of the watershed, we identify the most suitable methodology to quantify the surface run-off for the return period which is defined by the project; urban networks are commonly designed for the 5yr or 10yr return period and checked against less frequent events (e.g. 25yr, 50yr and 100yr return period), whilst dams are designed for the Probable Maximum Precipitation which is comparable to the 10000yr return period event.

Global Precipitation Viewer

In the following interactive map you can see the Global Precipitation datasets from NASA's GPM mission. More information can be found here.