Evaluation of the possible effectiveness of sustainable urban drainage systems within the urban catchment of the Water of Leith

Abstract

Urbanization brings great socio-economic progress, but also can cause damage to the urban living environment, especially surface flooding in urban areas. In order to cope with this problem sustainably, Sustainable urban Drainage Systems (SuDS) have been developed in Scotland to ameliorate urban flooding, which can also be treated as amenity in urban areas. Modern SuDS facilities form part of Blue-Green Infrastructures (BGI).

There are 2 major categories of BGI: Source Control Systems (SCS) and Site/Regional Control Systems (SRCS). SCS are good at control urban flooding while SRCS do well in contaminants treatment. Several projects are in progress to improve or develop BGI. However, surface flooding is still predicted to cause nearly £6 million of damage annually in potentially flooding-vulnerable areas of Scotland. And the urban part of Water of Leith Catchment (WLC) is chosen as the study area, which is one of most flooding-vulnerable catchments in Scotland.

In order to retrofit existing BGI to improve their performances, this research use hydrological indexes and socio-economic indexes to evaluate functionality of BGI in all data zones, which are 2011 census data zones.

This research uses a clustering method, called Self-Organizing Map (SOM) to identify the suitable BGI of each data zone which could be retrofitted or regarded as examples within the study area by dividing the study area into 4 clusters. Geographically Weighted Regression (GWR) are used to find whether SCS or SRCS should be retrofitted, based on the standardized residual of each data zones.

88 data zones were identified, where BGI should be retrofitted (33 data zones for SCS and 55 data zones for SRCS). 115 data zones were recognized as example sites of BGI (72 data zones for SCS and 43 data zones for SRCS).