Wet Weather and Water Quality - 30 Years Later and All the Same Questions Remain

Within the last three years, the United States Environmental Protection Agency (USEPA) has taken two significant steps with respect to regulating the quality of storm water discharges from urban areas. The first of these is the development of Final Rules and Regulations for Storm Water Discharges from urban areas with separated waste water and storm drainage systems. Published in late 1990, the rule requires all municipalities with populations over 100,000 to apply for a permit to discharge storm water under the USEPA's National Pollutant Discharge Elimination System (NPDES). The permit application must include, among other things, a plan to reduce the pollutants in urban runoff to the “Maximum Extent Practicable”. The second step is the publication in January, 1993, of a draft policy regulating discharges from combined sewer systems. These two initiatives for water quality control of wet weather discharges from urban drainage systems are significant steps forward in a national program to reduce pollution contributions to receiving waters in urban areas. This paper provides an overview of the requirements of these two wet weather water quality management programs.

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Integrated water quality and environmental cost-benefit modelling for the management of the River Tame

Water Science & Technology ◽

10.2166/wst.1999.0208 ◽

1999 ◽

Vol 39 (4) ◽

pp. 213-220 ◽

Cited By ~ 2

Author(s):

Bob Crabtree ◽

Matt Hickman ◽

Dave Martin

Keyword(s):

Water Quality ◽

Cost Benefit ◽

Weather Conditions ◽

Environmental Cost ◽

Northern Portion ◽

Wet Weather ◽

The 1960S ◽

The Uk ◽

Water Quality Impact

In the UK, the River Tame catchment covers an area of about 1,400 km2 and forms the northern portion of the Birmingham Conurbation. In the 1960s, wet weather conditions in Birmingham could result in the total depletion of oxygen in the River Trent below the Tame confluence. Construction of a system of purification lakes at Lea Marston, below the major polluting discharges, was completed in the early 1980s. Today, the operation of the Lea Marston Lakes significantly improves the quality of the Tame. However, wet weather pollution episodes in the Tame continues to have a severe impact on water quality in the Trent and put major fisheries at risk. This paper reports on the outcome of an integrated environmental impact and cost-benefit assessment modelling study into the future strategic management of the Lea Marston Lakes. The study demonstrated that the Lea Marston Lakes provide an economically justifiable method for reducing the water quality impact of the Birmingham conurbation and as a result will continue to be operated.

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Water quality criteria for total suspended solids (TSS) in urban wet-weather discharges

Water Science & Technology ◽

10.2166/wst.2006.623 ◽

2006 ◽

Vol 54 (6-7) ◽

pp. 355-362 ◽

Cited By ~ 10

Author(s):

L. Rossi ◽

R. Fankhauser ◽

N. Chèvre

Keyword(s):

Water Quality ◽

Urban Areas ◽

Suspended Solids ◽

Quality Criteria ◽

Aquatic Organisms ◽

Total Suspended Solids ◽

Water Quality Criteria ◽

Combined Sewer Overflows ◽

Wet Weather ◽

Rain Events

Total suspended solids (TSS) from combined sewer overflows (CSOs) and stormwater discharges represent a crucial parameter for evaluating wet-weather pollution in urban areas. In fact, the increase of TSS in water during rain events can have ecotoxic effects on aquatic organisms. Furthermore, major potentially harmful substances such as heavy metals, PAHs and organic matter are adsorbed onto TSS and later settle on sediment. Water quality criteria for TSS consequently enable the risk of wet-weather pollution to be assessed, for instance to avoid detrimental effects on aquatic organisms. The criteria proposed in this study cover the short-term impact of TSS on fish (acute quality criteria AQC), taking into account the duration of their exposure in the receiving water. The concentration-exposure duration-effect curve proposed here thus predicts “ill effects” on fish for different exposure times and TSS concentrations. The ecotoxic effects of adsorbed pollutants are also taken into account with an additional safety factor. We implement this TSS criteria in a software that allows us to estimate the number of rain events that exceed a given morbidity threshold for fishes per year.

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