Articles
Implications of sustainable drainage system design on its infiltration rate and maximum water capacity
Article number
1429_26
Pages
217 – 224
Language
English
Abstract
Climate change in North-West Europe entails extreme drought periods but also heavy rainfall episodes.
These negative effects are strengthened in the densely populated region of Flanders with an average paved surface area of 16%. It is therefore essential to minimize water drainage to sewage systems and refill groundwater reserves locally.
Aboveground infiltration facilities such as sustainable drainage systems (SuDS) have the advantage that they are much cheaper than belowground infiltration systems.
Moreover, they contribute to green infrastructure and biodiversity in cities.
This research takes a deeper look at the functioning of a SuDS, and the impact of different substrates and plant rooting types on its infiltration rate.
First, a range of substrates was tested on its infiltration rate and maximum water capacity.
Good draining substrates such as broken shells and broken lightweight expanded clay aggregates (LECA) were tested in combination with additives such as bentonite, as the latter offers benefits regarding maximum water capacity and plant survival in drought periods.
The results were modelled by the Sirio model for a local case study and the impact on overflow volumes was assessed.
The extra substrate parameters may enhance future model simulations, which currently underestimate the real situation.
Secondly, 3 substrates were selected, and the impact of different plant rooting types (deep rooting shrubs, deep rooting perennials, shallow rooting perennials, shallow rooting lawns, flower meadows) on the infiltration rate of bioswales was assessed.
The results showed a significant impact of the substrate used in SuDS, but also the plant rooting type may enhance or inhibit the infiltration rate locally.
This effect is, however, dependent on the substrate type.
This study showed that SuDS design can be optimized by changing substrate mixtures and plant assortment.
These negative effects are strengthened in the densely populated region of Flanders with an average paved surface area of 16%. It is therefore essential to minimize water drainage to sewage systems and refill groundwater reserves locally.
Aboveground infiltration facilities such as sustainable drainage systems (SuDS) have the advantage that they are much cheaper than belowground infiltration systems.
Moreover, they contribute to green infrastructure and biodiversity in cities.
This research takes a deeper look at the functioning of a SuDS, and the impact of different substrates and plant rooting types on its infiltration rate.
First, a range of substrates was tested on its infiltration rate and maximum water capacity.
Good draining substrates such as broken shells and broken lightweight expanded clay aggregates (LECA) were tested in combination with additives such as bentonite, as the latter offers benefits regarding maximum water capacity and plant survival in drought periods.
The results were modelled by the Sirio model for a local case study and the impact on overflow volumes was assessed.
The extra substrate parameters may enhance future model simulations, which currently underestimate the real situation.
Secondly, 3 substrates were selected, and the impact of different plant rooting types (deep rooting shrubs, deep rooting perennials, shallow rooting perennials, shallow rooting lawns, flower meadows) on the infiltration rate of bioswales was assessed.
The results showed a significant impact of the substrate used in SuDS, but also the plant rooting type may enhance or inhibit the infiltration rate locally.
This effect is, however, dependent on the substrate type.
This study showed that SuDS design can be optimized by changing substrate mixtures and plant assortment.
Authors
S. Adriaenssens, T. Masschelein, A. Colpaert, B. De Bock, H. Denaeghel, R. De Sutter, F. Debersaques, B. Gobin
Keywords
sustainable drainage systems, rooting type, Sirio, substrate mixture
Online Articles (57)