Effects of Plant on Pollutant Removal Rate n Surface-flow Constructed Wetlands

This report describes the development of a methodology to theoretically assess the effectiveness of structural BMPs with regard to their treatment of selected stormwater pollutants (metals, polyaromatic hydrocarbons and herbicides). The result is a prioritisation, in terms of pollutant removal efficiency, of 15 different BMPs which can inform stormwater managers and other stakeholders of the best available options for the treatment of urban runoff pollutants of particular environmental concern. Regardless of the selected pollutant, infiltration basins and sub-surface flow constructed wetlands are predicted to perform most efficiently with lagoons, porous asphalt and sedimentation tanks being the least effective systems for the removal of pollutants. The limitations of the approach in terms of the variabilities in BMP designs and applications are considered.

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The integration of constructed wetlands into a treatment system for airport runoff

Water Science & Technology ◽

10.2166/wst.2001.0868 ◽

2001 ◽

Vol 44 (11-12) ◽

pp. 469-476 ◽

Cited By ~ 23

Author(s):

D.M. Revitt ◽

P. Worrall ◽

D. Brewer

Keyword(s):

Constructed Wetlands ◽

Surface Runoff ◽

Pilot Scale ◽

Surface Flow ◽

Pollutant Removal ◽

Treatment System ◽

Effluent Water ◽

Surface Areas ◽

Scale Surface ◽

Surface Flow Constructed Wetlands

A new surface runoff treatment system has been designed for London Heathrow Airport, which incorporates separate floating constructed wetlands or reedbeds and sub-surface flow constructed wetlands as major pollutant removal systems. The primary requirement of the newly developed treatment system is to control the concentrations of glycols following their use as de-icers and anti-icers within the airport. The ability of reedbeds to contribute to this treatment role was fully tested through pilot scale, on-site experiments over a 2 year period. The average reductions in runoff BOD concentrations achieved by pilot scale surface flow and sub-surface flow reedbeds were 30.9% and 32.9%, respectively. The corresponding average glycol removal efficiencies were 54.2% and 78.3%, following shock dosing inputs. These treatment performances are used to predict the required full scale constructed wetland surface areas needed to attain the desired effluent water quality. The treatment system also incorporates aeration, storage and, combined with reedbed technology, has been designed to reduce a mixed inlet BOD concentration of 240 mg/l to less than 40 mg/l for water temperatures varying between 6°C and 20°C.

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How Long, Narrowly Constructed Wetlands Purify Irrigation Return Water: A Case Study of Ulansuhai Lake, China

Advances in Meteorology ◽

10.1155/2015/142036 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Xufeng Mao ◽

Donghai Yuan ◽

Liansheng He ◽

Xiaoyan Wei ◽

Qiong Chen ◽

...

Keyword(s):

Constructed Wetlands ◽

Constructed Wetland ◽

Sharp Decrease ◽

Surface Flow ◽

Pollutant Removal ◽

Single Type ◽

Return Water ◽

Pollutant Concentrations ◽

Pollutants Removal ◽

Surface Flow Constructed Wetlands

The use of constructed wetlands (CWs) in the treatment of raw wastewater in China has proved to be very successful in recent decades. However, it is not known whether surface-flow constructed wetlands can effectively purify irrigation return water. To investigate the performance of a constructed wetland in terms of meeting the goals of pollutant purification, the 8th drainage of Ulansuhai Lake was used for this study. Pollutant removal performances, as well as hydrological characteristic variations in relation to specific characteristics of plants, were investigated utilizing two years of monthly average data. The results indicated that surface-flow constructed wetlands can effectively change the physical characteristics of return water and lead to a sharp decrease in pollutant concentrations. The 1200 m long, narrowly constructed wetland resulted in the average reduction rates of total nitrogen (TN) and total phosphorus (TP) of up to 22.1% and 21.5%, respectively. The overall purification efficient of the constructed wetland presented seasonal variations in four different monitoring periods (May, July, September, and November). Constructed wetlands with multiple types of plants exhibited higher efficiencies in pollutants removal than those with a single type of plant. The current study can provide meaningful information for the treatment of agricultural wastewater.

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IDENTIFYING THE MOST SUITABLE AREAS FOR SURFACE FLOW WETLAND CONSTRUCTION IN LITHUANIA

Proceedings of the 7th International Scientific Conference Rural Development 2015 ◽

10.15544/rd.2015.060 ◽

2015 ◽

Author(s):

Antanas DUMBRAUSKAS ◽

Nijolė BASTIENĖ ◽

Petras PUNYS

Keyword(s):

Constructed Wetlands ◽

Ecological Status ◽

Surface Flow ◽

Gis Analysis ◽

Proximity Analysis ◽

Wetland Construction ◽

The Mean ◽

Two Phases ◽

Terrain Features ◽

Surface Flow Constructed Wetlands

GIS-based approach to find the suitable sites for surface flow constructed wetlands was employed for the Lithuanian river basins with low ecological status. According to the nature of the analysed criteria the flowchart consists of two phases. Criteria used include hydrographical network, soil properties, terrain features, land use, etc. Some of them have strictly defined values (constraints), and other ranges within certain limits (factors). Limited criteria were analysed using rejection principle and influencing factors using proximity analysis and overlay methods. Selecting the potential sites using standard GIS analysis tools there was estimated about 3286 sites for possible wetlands with the mean area of inflow basin about 4 km2 in the basins of water bodies at risk.

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