Water Quality Improvement Performance of Geotextiles Within Permeable Pavement Systems: A Critical Review

Abstract

Sustainable drainage systems (SuDS; or best management practices) are increasingly being used as ecological engineering techniques to prevent the contamination of receiving watercourses and groundwater. Permeable paving is a SuDS technique, which is commonplace in car parks, driveways and minor roads where one of their functions is to improve the quality of urban runoff. However, little is known about the water quality benefits of incorporating an upper geotextile within the paving structure. The review focuses on five different categories of pollutants: organic matter, nutrients, heavy metals, motor oils, suspended solids originating from street dust, and chloride. The paper critically assesses results from previous international tests and draws conclusions on the scientific rigour and significance of the data. Findings indicate that only very few studies have been undertaken to address the role of geotextiles directly. All indications are that the presence of a geotextile leads only to minor water quality improvements. For example, suspended solids are being held back by the geotextile and these solids sometimes contain organic matter, nutrients and heavy metals. However, most studies were inconclusive and data were often unsuitable for further statistical analysis. Further long-term research on industry-relevant, and statistically and scientifically sound, experimental set-ups is recommended.

The Influence of Geotextile Type and Position in a Porous Asphalt Pavement System on Pb(II) Removal from Stormwater

“…The difference in Pb 2+ removal efficiencies between the PA systems containing a non-woven geotextile and those of a woven geotextile is a reflection of the suggestion that various types of geotextile membranes used in PA systems can directly affect the system removal capacity of Pb 2+ . Cook and Scholz note in their studies [4,33] that non-woven geotextile is the preferred geotextile type for permeable paving applications because of its better filtration and separation properties than woven geotextile. But no specific experimental data is presented for its removal capacity of heavy metals from stormwater or aqueous solutions.…”

“…In particular, stormwater runoff generated by an urban impervious surface has been regarded as an important contributor to the degradation of receiving aquatic systems because it carries contaminants accumulating between storm events in the urban environment. These pollutants include suspended solids, organic matter, nutrients, heavy metals, oils and even polycyclic aromatic hydrocarbons (PAHs) [3,4]. To mitigate these negative effects, and potentially start using stormwater as a resource instead of a waste product, low impact development (LID) options such as permeable pavement systems (PPS), are seeing an increase in implementation in low-traffic areas in place of impermeable surfaces [5][6][7].…”

“…), overlying a bedding course for PICPs and a choker course for PA and PC, and then a reservoir structure for stormwater temporary storage (also referred to as base course, which can involve an open graded aggregate bed with varying depths depending on water storage requirements and frost depth) [11,12]. Permeable geotextile membrane is traditionally used at one or two levels within the PPS to separate the layers and prevent migration of stones and gravel, as well as for strengthening purpose [4,6,13,14].…”

Potential for Potable Water Savings in Buildings by Using Stormwater Harvested from Porous Pavements

“…According to Khastagir and Jayasuriya [8], in Melbourne, Australia, the use of rainwater for domestic purposes has become increasingly popular since the city faced severe drought for twelve consecutive years, with annual rainfall below average. However, stormwater collected from paved roads may contain high amounts of pollutants [28]. Roads can be considered sources of various pollutants (suspended solids, heavy metals, hydrocarbons).…”

Changes of Permeability of Nonwoven Geotextiles due to Clogging and Cyclic Water Flow in Laboratory Conditions

“…Geosynthetics are modern engineering materials, which have been widely used in soil structures for reinforcing, separation, filtration, and drainage [1][2][3][4][5][6][7][8][9][10]. The main functions of geotextile filters are to prevent the movement of fine particles from the base soil and to avoid the development of excessive pore water pressure on the soil-geotextile filter interface.…”