REED BED TREATMENT SYSTEMS: EXPERIMENTAL GRAVEL BEDS AT GRAVESEND — THE SOUTHERN WATER EXPERIENCE

Reed bed treatment is put in the context of a major water company’s need to provide reliable, high quality, effluents from small sewage treatment works whilst seeking to minimise running costs. Design and operational information is given for reed bed applications in Severn Trent Water. Performance details are provided for application to secondary, tertiary and storm overflow treatment. The results give particular confidence in the system’s ability to deliver very high quality effluents when used for tertiary treatment, the company’s biggest application. Reed beds work well against less demanding criteria for secondary treatment at small sites and show great promise for storm overflow treatment.

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Reed bed treatment systems for sewage treatment in the United Kingdom - the first 10 years’ experience

Water Science & Technology ◽

10.2166/wst.1995.0154 ◽

1995 ◽

Vol 32 (3) ◽

pp. 317-327 ◽

Cited By ~ 12

Author(s):

P. Cooper ◽

B. Green

Keyword(s):

Root Zone ◽

Sewage Treatment ◽

Horizontal Flow ◽

Water Industry ◽

Soil Systems ◽

Design Changes ◽

Flow Systems ◽

Group A ◽

Reed Bed ◽

The Uk

The UK Water Industry first became interested in Reed Bed Treatment Systems for sewage in 1985. Early problems were experienced with soil-based horizontal-flow systems of the Root Zone type. The problems were overcome by national co-ordination of a development programme and international co-operation by an EC Expert Contact Group. A number of different types of systems have now been developed and the systems are now being accepted. The paper reviews the development of these systems for secondary and tertiary treatment and nitrification and mentions development of systems for other forms of treatment. The design changes made to overcome the problems are described. These include the gradual move to the use of gravel-based systems because of the difficulty experienced with over-land flow in the soil systems. The sizing of the systems is described together with performance data for the original horizontal-flow and the more recently developed vertical-flow systems. Treatment at secondary and tertiary levels is illustrated and the potential for nitrification. Early problems with reed growth have been overcome by planting with port-grown seedlings. After 10 years the process is generally accepted by the Water Industry as an appropriate treatment for villages and there are now between 200 and 300 systems in operation.

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Optimising the performance of a lab-scale tidal flow reed bed system treating agricultural wastewater

Water Science & Technology ◽

10.2166/wst.2004.0490 ◽

2004 ◽

Vol 50 (8) ◽

pp. 65-72 ◽

Cited By ~ 25

Author(s):

Y.Q. Zhao ◽

G. Sun ◽

C. Lafferty ◽

S.J. Allen

Keyword(s):

Tidal Flow ◽

High Strength ◽

Pollutant Removal ◽

Inorganic Pollutants ◽

Operational Conditions ◽

Agricultural Wastewater ◽

Major Route ◽

Reed Bed ◽

Ammoniacal Nitrogen Removal

A gravel-based tidal flow reed bed system was operated with three different strategies in order to investigate its optimal performance for the treatment of a high strength agricultural wastewater. According to the three strategies, individual reed beds were saturated and unsaturated with the wastewater for different periods while reasonably stable hydraulic and organic loadings were maintained. Experimental results demonstrated that the system produced the highest pollutant removal efficiencies with a relatively short saturated period and long unsaturated period, highlighting the importance of oxygen transfer into reed bed matrices during the treatment. Significant removals of some major organic and inorganic pollutants were achieved under all three operational conditions. Nitrification was not the major route of ammoniacal-nitrogen removal when the system was under high organic loading. Due to the filtration of suspended solids and the accumulation of biomass, gradual clogging of the reed bed matrices took place, which caused concerns over the long-term efficiency of the tidal flow system.

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Late Glacial, Early Holocene and Late Holocene life at the interface of a distinct landscape — relationship of humans and environments in the Sub-Carpathian region (N Hungary)

Open Geosciences ◽

10.2478/s13533-012-0107-x ◽

2012 ◽

Vol 4 (4) ◽

Cited By ~ 1

Author(s):

Gábor Bácsmegi ◽

Pál Sümegi ◽

Tünde Törőcsik

Keyword(s):

Water Level ◽

Late Holocene ◽

Late Glacial ◽

Climatic Effects ◽

Natural Landscape ◽

Carpathian Region ◽

Modern Age ◽

Reed Bed ◽

Relationship Of ◽

Historical Methods

AbstractRelationships between the communities and environment surrounding these communities can be disclosed by the application of different archeological, geological and environmental historical methods. This includes the deployment of numerous tools in scientific investigation including the application of chronological, sedimentological, geochemical and paleoecological analytical methods on sequences accumulated in historical catchment basins of peat-bog. The Nádas-tó at Nagybárkány is a small peatbog in the northern part of Hungary, on the Sub-Carpathian region. The formation of the lake can be traced back to the Late Glacial period. The sediments deposited in the lakebed provide a record of climatic and hydrologic changes. A higher water level could be demonstrated from the Late Glacial to the Mid-Holocene, when the reed-beds covered a small area only. This was followed by a hiatus spanning ca. 4400 years, caused by the deepening and cleaning of the lakebed during the Late Iron / Imperial Age, between 2100 - 1900 cal BP years. After this change the water level decreased and the water quality was more eutrophic. A reed-bed evolved around the lake. Paludification started with a bulrush floating mat phase at the close of the Middle Age, ca. 1500 cal AD years. The endowments and settlement pattern persisted from the Neolithic onwards until the terminal Modern Age, when measures aimed to ordain the area substantially altered the natural landscape. Although some anthropogenic disturbances can be reconstructed in the development of the peatland, some climatic effects and authogenic processes might be separated by paleoecological analyses.

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The application of wetland technology for copper removal from distillery wastewater: a case study

Water Science & Technology ◽

10.2166/wst.2009.729 ◽

2009 ◽

Vol 60 (11) ◽

pp. 2759-2766 ◽

Cited By ~ 3

Author(s):

C. Murphy ◽

P. Hawes ◽

D. J. Cooper

Keyword(s):

Metal Removal ◽

Copper Removal ◽

Ionic Form ◽

Reed Beds ◽

Organic Species ◽

Treatment Processes ◽

Distillery Wastewater ◽

Reed Bed ◽

Performance Results

The ability of reed beds to remove significant levels of metals from effluent streams is well cited in the literature. Various methods of removal have been postulated and demonstrated including physical methods such as filtration and settlement, precipitation when the metal is present as a salt and adsorption to organic species or take up by macrophytes when the metal is in a soluble or ionic form. Consequently, reed beds have been used in a variety of applications for metal removal in water treatment processes. The distillation process for whisky generates an effluent containing a significant amount of copper which is scoured from the copper stills during the process and cleaning operations. High soluble copper concentrations can breach discharge consents. A horizontal subsurface flow reed bed system has been designed and installed for copper removal at a distillery in Scotland. This paper presents the findings of the literature search, outlines the design of the bed and reviews the performance results.

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Multiple controls on sediment grain properties of Peruvian coastal river basins

10.5194/esurf-2017-8 ◽

2017 ◽

Author(s):

Camille Litty ◽

Fritz Schlunegger ◽

Willem Viveen

Keyword(s):

Grain Size ◽

Drainage Basin ◽

River Basins ◽

Humid Climate ◽

Sediment Properties ◽

Peruvian Andes ◽

Southern Group ◽

Gravel Beds ◽

The North ◽

Grain Properties

Abstract. Twenty-one coastal rivers located on the western Peruvian margin were analyzed to determine the relationships between fluvial and environmental processes and sediment grain properties such as grain size, roundness and sphericity. Modern gravel beds were sampled along a north-south transect on the western side of the Peruvian Andes, and at each site the long a-axis and the intermediate b-axis of about 500 pebbles were measured. Morphometric properties such as river gradient, catchment size and discharge of each drainage basin were determined and compared against measured grain properties. Grain size data show a constant value of the D50 percentile all along the coast, but an increase in the D84 and D96 values and an increase in the ratio of the intermediate and the long axis from south to north. Our results then yield better-sorted and less spherical material in the south when compared to the north. No correlations were found between the grain size and the morphometric properties of the river basins when considering the data together. Grouping the results in a northern and southern group shows better-sorted sediments and lower D84 and D96 values for the southern group of basins. Within the two groups, correlations were found between the grain size distributions and morphometric basins properties. Our data indicates that fluvial transport is the dominant process controlling the erosion, transport and deposition of sediment in the southern basins while we propose a geomorphic control on the grain size properties in the northern basins. Sediment properties in the northern and southern basins could not be linked to differences in tectonic controls. On the other hand, the north-south trend in the grain size and in the b/a ratio seems controlled by a shift towards a more humid climate and towards a stronger El Nino impact in northern Peru. But, generally speaking, the resulting trends and differences in sediment properties seem controlled by differences in the complex geomorphic setting along the arc and forearc regions.

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On-site domestic wastewater treatment by reed bed in the moist subtropics

Water Science & Technology ◽

10.2166/wst.2001.0851 ◽

2001 ◽

Vol 44 (11-12) ◽

pp. 353-360 ◽

Cited By ~ 10

Author(s):

L. Davison ◽

T. Headley ◽

M. Edmonds

Keyword(s):

New South ◽

Domestic Wastewater ◽

Moisture Loss ◽

Reed Beds ◽

Treatment Performance ◽

South Wales ◽

Domestic Wastewater Treatment ◽

Australian State ◽

North Eastern ◽

Reed Bed

This paper summarises the results of studies on four subsurface flow wetlands (reed beds) located in the moist sub-tropical north eastern corner of the Australian state of New South Wales. The reed beds, which are subjected to a variety of effluent types, all have a gravel substrate planted with Phragmites australis. All four units were found to maintain satisfactory treatment performance year round. Mean removal efficiencies ranged from 56% to 90% (SS), 70% to 93% (BOD), 38% to 66% (TN), 87% to 99.8% (Faecal coliforms), and 42% to 70% (TP - with one seasonal result of 0% for the eight year old unit) for the four reed beds. After eight years in operation the oldest reed bed was showing signs of phosphorus saturation with outlet TP concentrations exceeding inlet concentrations on some occasions. The youngest reed bed studied appeared to be operating efficiently after five months. A summer water balance on one of the reed beds revealed an average crop factor of 1.6 and a moisture loss to atmosphere of 40% of influent flow. Treatment performance (particularly for TN and SS) was found to be negatively correlated with rainfall during one study. The paper discusses the implications of the above results for on-site system designers and regulators and identifies areas for further investigation.

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