A Minimum Data Set of Water Quality Parameters to Assess and Compare Treatment Efficiency of Stormwater Facilities

Abstract

Urban stormwater runoff is often of poor quality, impacting aquatic ecosystems and limiting the use of stormwater runoff for recreational purposes. Several stormwater treatment facilities (STFs) are in operation or at the pilot testing stage, but their efficiencies are neither well documented nor easily compared due to the complex contaminant profile of stormwater and the highly variable runoff hydrograph. On the basis of a review of available data sets on urban stormwater quality and environmental contaminant behavior, we suggest a few carefully selected contaminant parameters (the minimum data set) to be obligatory when assessing and comparing the efficiency of STFs. Consistent use of the minimum data set in all future monitoring schemes for STFs will ensure broad-spectrum testing at low costs and strengthen comparability among facilities. The proposed minimum data set includes: (i) fine fraction of suspended solids (<63 μm), (ii) total concentrations of zinc and copper, (iii) total concentrations of phenanthrene, fluoranthene, and benzo(b,k)fluoranthene, and (iv) total concentrations of phosphorus and nitrogen. Indicator pathogens and other specific contaminants (i.e., chromium, pesticides, phenols) may be added if recreational or certain catchment-scale objectives are to be met. Issues that need further investigation have been identified during the iterative process of developing the minimum data set.

Controlling Stormwater Quality with Filter Soil—Event and Dry Weather Testing

“…Removal of SSis crucial in treatment of urban stormwater runoff since the solids often carry a large part of the pollutant load [3]. Studies performed by [16] showed that even small particles are well retained in filter soil, and the main part of the particles present in the percolate at both locations are probably particles that have been mobilized in the filter soil, rather than the particles entering with the stormwater runoff.…”

“…Infiltration elements are designed to contribute to urban drainage by retaining stormwater runoff locally and thereby decreasing downstream flow rates and volumes. Additionally, the infiltration elements may function as stormwater treatment facilities because pollutants are retained by processes such as sedimentation, filtration, adsorption and in some cases degradation of pollutants present in the stormwater runoff that have accumulated during dry weather on the urban surfaces [3]. The infiltration capacity as well as the treatment capacity depends on the media used in the facility, and often an engineered soil mixture is used.…”

Green infrastructure for flood-risk management in Dar es Salaam and Copenhagen: exploring the potential for transitions towards sustainable urban water management

“…One such complexity is the competition for space in the urban landscape vis-à-vis the frequently divergent interests of the numerous stakeholders. Another form of relational complexity in the implementation of city-wide SUDS retrofits arises from the intrinsic need for a transdisciplinary and multi-tier approach (Ingvertsen et al, 2011).…”

A planning framework for sustainable urban drainage systems

“…The contaminant profile of stormwater mnoff is highly variable due to the many sources, including fuel and petrol combusting products, abrasive and corrosion products from vehicles, roads and buildings surfaces, atmospheric depositions and animal droppings, as well as pesticides, fertilizers, paints and other materials regularly applied to urban surfaces (Tsihrintzis & Hamid, 1997;Göbel et al, 2007;Ingvertsen et al, 2011). Contaminant concentration levels are influenced by traffic intensity, the length of the preceding dry weather period and by the character of the rain event (Deletic, 1998).…”