Novel sorption media material for catch basin insert filters to remove pollutants from urban runoff

City-scale urban greening is expanding wildlife habitat in previously less hospitable urban areas. Does this transformation also prompt a reckoning with the longstanding idea that cities are places intended to satisfy primarily human needs? I pose this question in the context of one of North America's most ambitious green infrastructure programmes to manage urban runoff: Philadelphia's Green City, Clean Waters. Given that the city's green infrastructure plans have little to say about wildlife, I investigate how wild animals fit into urban greening professionals' conceptions of the urban. I argue that practitioners relate to urban wildlife via three distinctive frames: 1) animal control, 2) public health and 3) biodiversity, and explore the implications of each for peaceful human-wildlife coexistence in 'greened' cities.

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Large-Scale Application of Biofiltration Swale Runoff Management Practices

Water Practice & Technology ◽

10.2166/wpt.2007.049 ◽

2007 ◽

Vol 2 (2) ◽

Author(s):

William C. Lucas

Keyword(s):

Large Scale ◽

Management Practices ◽

Peak Flow ◽

Low Impact Development ◽

Urban Runoff ◽

Management Model ◽

Check Dams ◽

Runoff Reduction ◽

Impervious Area ◽

Hydrologic Responses

Retaining rainfall where it lands is a fundamental benefit of Low Impact Development (LID). The Delaware Urban Runoff Management Model (DURMM) was developed to address the benefits of LID design. DURMM explicitly addresses the benefits of impervious area disconnection as well as swale flow routing that responds to flow retardance changes. Biofiltration swales are an effective LID BMP for treating urban runoff. By adding check dams, the detention storage provided can also reduce peak rates. This presentation explores how the DURMM runoff reduction approach can be integrated with detention routing procedures to project runoff volume and peak flow reductions provided by BMP facilities. This approach has been applied to a 1,200 unit project on 360 hectares located in Delaware, USA. Over 5 km of biofiltration swales have been designed, many of which have stone check dams placed every 30 to 35 meters to provide detention storage. The engineering involved in the design of such facilities uses hydrologic modeling based upon TR-20 routines, as adapted by the DURMM model. The hydraulic approach includes routing of flows through the check dams. This presentation summarizes the hydrological network, presents the hydrologic responses, along with selected hydrographs to demonstrate the potential of design approach.

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Laboratory Prediction of Phosphorus Release from Deciduous Leaves to Urban Runoff

Water Quality Research Journal ◽

10.2166/wqrj.1995.024 ◽

1995 ◽

Vol 30 (2) ◽

pp. 243-246 ◽

Cited By ~ 8

Author(s):

Heather Culbert ◽

Robert France

Keyword(s):

Total Phosphorus ◽

Empirical Equation ◽

Urban Runoff ◽

Phosphorus Release ◽

Total Export ◽

Forested Watershed ◽

Distilled Water ◽

Trembling Aspen ◽

Urban Catchments

Abstract In urban centres, leaves are customarily gathered and temporarily stored in large roadside piles prior to their transport to disposal sites. To simulate the release of total phosphorus to urban runoff, birch and trembling aspen leaves were leached with distilled water in laboratory flasks. There was no difference in rate of total phosphorus release between oven-dried and non-dried leaves. An empirical equation developed from these data and knowledge of the litterfall rates for southern Canada indicated that leaves yielded from 11 to 45 mg TP m−2 of forested watershed. This amount represents up to 5% of the total export of total phosphorus from urban catchments and has the potential to exacerbate eutrophication of municipal waters if leaf pickup is not promptly enforced.

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Incorporating concepts from physical theory into stochastic modelling of urban runoff pollution

Water Science & Technology ◽

10.2166/wst.1998.0044 ◽

1998 ◽

Vol 37 (1) ◽

pp. 179-185

Author(s):

Morten Grum

Keyword(s):

Stochastic Model ◽

Continuous Time ◽

Measurement Errors ◽

Physical Theory ◽

Oxygen Demand ◽

Stochastic Modelling ◽

Urban Runoff ◽

Primary Input ◽

Deterministic Modelling ◽

Runoff Pollution

On evaluating the present or future state of integrated urban water systems, sewer drainage models, with rainfall as primary input, are often used to calculate the expected return periods of given detrimental acute pollution events and the uncertainty thereof. The model studied in the present paper incorporates notions of physical theory in a stochastic model of water level and particulate chemical oxygen demand (COD) at the overflow point of a Dutch combined sewer system. A stochastic model based on physical mechanisms has been formulated in continuous time. The extended Kalman filter has been used in conjunction with a maximum likelihood criteria and a non-linear state space formulation to decompose the error term into system noise terms and measurement errors. The bias generally obtained in deterministic modelling, by invariably and often inappropriately assuming all error to result from measurement inaccuracies, is thus avoided. Continuous time stochastic modelling incorporating physical, chemical and biological theory presents a possible modelling alternative. These preliminary results suggest that further work is needed in order to fully appreciate the method's potential and limitations in the field of urban runoff pollution modelling.

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