scholarly journals First Flush Characteristics in Separate Sewer Stormwater and Implications for Treatment

2020 ◽  
Vol 12 (12) ◽  
pp. 5063 ◽  
Author(s):  
Sara Egemose ◽  
Anne B. Petersen ◽  
Melanie J. Sønderup ◽  
Mogens R. Flindt
Keyword(s):  
Suspended Solids ◽  
Particulate Phosphorus ◽  
Water Volume ◽  
First Flush ◽  
Stormwater Treatment ◽  
Dry Period ◽  
Need For Treatment ◽  
Precipitation Characteristics ◽  
Catchment Size ◽  
Rain Events

The characteristics of stormwater need focus due to climate change. Paved areas and recipients receiving more stormwater have an enhanced need for treatment before discharge to remove suspended solids, nutrients and xenobiotics. To handle and treat stormwater efficiently, knowledge concerning first flush patterns is crucial. Therefore, we have studied 12 entire rain events and correlated water volume, suspended solids, and dissolved and particulate phosphorus to catchment characteristics and precipitation characteristics. We have mainly studied smaller rain events (average 12.6 mm), as nearly 90% of the events in the studied catchment are <10 mm. We revealed first flush tendencies in 50% of the rain events, concerning both suspended solids and phosphorus. We also found significant correlations between catchment size and discharged masses, and most importantly between precipitation patterns and discharged mass per volume. A long dry period and low amount of rain during the previous event, as well as high rain intensity, gives a high chance of first flush. We conclude that stormwater treatment should focus on the initial part of the event, especially in areas with a lack of space and/or economy to handle and treat the entire event.

Treatment of road runoff by coagulation/flocculation and sedimentation

2019 ◽  
Vol 79 (3) ◽  
pp. 518-525 ◽  
Author(s):  
F. Nyström ◽  
K. Nordqvist ◽  
I. Herrmann ◽  
A. Hedström ◽  
M. Viklander
Keyword(s):  
Laboratory Investigation ◽  
Treatment Effect ◽  
Metal Content ◽  
Suspended Solids ◽  
Metal Reduction ◽  
Stormwater Treatment ◽  
Road Runoff ◽  
Coagulation Process ◽  
Before And After ◽  
Rain Events

Abstract A laboratory investigation of the treatment potential of a coagulation process in the context of stormwater treatment was undertaken. The initial 25 L road runoff generated from four rain events was collected and subjected to a jar-testing regime with two commercial coagulants. The treatment effect was assessed by analysing the runoff before and after treatment for turbidity, suspended solids and metal content. The coagulation process resulted in particle and total metal reduction of more than 90% compared to 40% for only sedimentation. Up to 40% reduction of dissolved Cr, Cu and Pb was also observed compared to 0% for sedimentation. This study shows that coagulation may be a useful process for stormwater treatment systems when the treatment requirements are high.

Particulate Phosphorus Dynamics in Headwater Streams

1988 ◽  
Vol 45 (2) ◽  
pp. 210-215 ◽  
Author(s):  
Yves T. Prairie ◽  
Jacob Kalff
Keyword(s):  
Predictive Power ◽  
Forest Cover ◽  
Headwater Streams ◽  
Particulate Phosphorus ◽  
Stream Channel ◽  
Slope Coefficient ◽  
Temporal Fluctuations ◽  
Phosphorus Dynamics ◽  
Catchment Size ◽  
Rain Events

We examined the dynamics of particulate phosphorus (PP) in seven headwater streams of southern Quebec draining catchments differing in size, extent of forest cover, and stream channel gradient. The extent of forest cover can be used to predict average [PP]. The magnitude of the temporal fluctuations (variance) in [PP] was strongly related to mean levels. While most streams showed positive relationships between discharge and [PP] in rain events, inverse relations were observed in two streams and possibly the result of the rapid exhaustion of PP. Inverse relationships were also seen in these two streams for samples collected outside rain events. We present a model based on channel gradient and extent of forest cover to predict the slope coefficient of [PP]–discharge relationships and also the occurrence of very rapid exhaustion. We then extend this model to include the influence of precipitation history and catchment size on [PP] in headwater streams. This model accounted for 60% of the variation of the pooled observations from all seven streams and is comparable in predictive power with stream-specific models published elsewhere in the literature.

scholarly journals Effects of Lanthanum Modified Bentonite and Polyaluminium Chloride on the Environmental Variables in the Water and Sediment Phosphorus Form in Lake Yanglan, China

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1947
Author(s):  
Ling Su ◽  
Chen Zhong ◽  
Lei Gan ◽  
Xiaolin He ◽  
Jinlei Yu ◽  
...  
Keyword(s):  
Suspended Solids ◽  
Soluble Reactive Phosphorus ◽  
Particulate Phosphorus ◽  
Modified Bentonite ◽  
Combined Application ◽  
Water And Sediment ◽  
Phosphorus Form ◽  
Labile P ◽  
Reactive Phosphorus ◽  
Polyaluminium Chloride

The application of lanthanum modified bentonite (Phoslock®) and polyaluminium chloride (PAC) is popular in the restoration of European temperate lakes; however, the effects of the application on the concentrations of phosphorus (P) in both the water and the sediments have been poorly evaluated to date. We studied the effects of the application of Phoslock® + PAC on the concentrations of total phosphorus (TP), particulate phosphorus (PP), soluble reactive phosphorus (SRP), total suspended solids (TSS) and chlorophyll a (Chla) in the water, and different P forms in the sediments, in an isolated part of Lake Yanglan. The results showed that the concentrations of TP, PP, SRP, TSS and Chla decreased significantly after the addition of Phoslock® + PAC. Moreover, the concentrations of labile-P, reductant-soluble-P and organic-P in the sediments were also significantly decreased after the Phoslock® + PAC application. However, the concentrations of both the stable apatite-P and residual-P in the sediments after application of Phoslock® + PAC were much higher than the pre-addition values, while the concentrations of metal-oxide-P did not differ significantly between the pre- and post- application conditions. Our findings imply that the combined application of Phoslock® and PAC can be used in the restoration of subtropical shallow lakes, to reduce the concentrations of P in the water and suppress the release of P from the sediments.

Dynamic behavior of suspended pollutants and particle size distribution in highway runoff

2002 ◽  
Vol 46 (11-12) ◽  
pp. 413-418 ◽  
Author(s):  
H. Furumai ◽  
H. Balmer ◽  
M. Boller
Keyword(s):  
Heavy Metals ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Suspended Solids ◽  
Dynamic Change ◽  
First Flush ◽  
Highway Runoff ◽  
Runoff Rate ◽  
Highway Drainage

Continuous runoff quality monitoring was conducted for one month at urban highway drainage with an area of 8.4 ha. Dynamic change of suspended solids and heavy metal concentrations were investigated during first flush periods, taking the particle size distribution into consideration. Except for Pb, the concentrations of TSS and heavy metals in runoff were within the range of the EMC reported in recent highway runoff research. Particle-bound heavy metals (Zn, Pb, and Cu) accounted for more significant pollutant loads than soluble fractions. Their content decreased with increasing total SS concentration in runoff samples. The results of particle size distribution (PSD) analysis of runoff samples indicate that high TSS concentration samples contained coarser particles. Based on the PSD results, a stepwise wash-off phenomenon of TSS under varying runoff rate conditions was explained by the different washoff behavior of fine (&lt; 20 mm) and coarser particles.

A new modeling approach for estimating first flush metal mass loading

2005 ◽  
Vol 51 (3-4) ◽  
pp. 159-167 ◽  
Author(s):  
L.-H. Kim ◽  
M. Kayhanian ◽  
S.-L. Lau ◽  
M.K. Stenstrom
Keyword(s):  
First Flush ◽  
Runoff Coefficient ◽  
Mass Loading ◽  
Storm Events ◽  
Metal Contaminants ◽  
Rain Intensity ◽  
Dry Period ◽  
Variable Parameters ◽  
Total Runoff ◽  
First Flush Effect

The purpose of this study was to investigate pollutant mass loading from major highways in Southern California, with emphasis on interpretation of event mean concentrations and first flush effects. The results of monitoring eight sites during the 1999–2002 storm seasons found that metal contaminants had higher concentrations at the early stages of storm events compared with other stages of rain storms. A new washoff model was developed to predict the event mean concentrations of metal contaminants taking first flush effect into account. Model variable parameters included average daily traffic, antecedent dry period, rain intensity, total runoff volume, and runoff coefficient. The results obtained using the washoff model were compared with measured values and found to fit well for heavy metals with R2 ranging from 0.8 to 0.95.

Innovative Stormwater Treatment Implementation at Parking Lot in China

2011 ◽  
Vol 255-260 ◽  
pp. 2718-2721
Author(s):  
Ru Zhang ◽  
Anthony N. Tafuri ◽  
Richard Field ◽  
Shaw L. Yu ◽  
Wen Bin Zhou ◽  
...  
Keyword(s):  
Suspended Solids ◽  
Low Impact Development ◽  
Oxygen Demand ◽  
Ammonia Nitrogen ◽  
Stormwater Treatment ◽  
Storm Events ◽  
Nonpoint Sources ◽  
Treatment Implementation ◽  
Parking Lot

Xikeng Reservoir is one of the major water supply reservoirs in Shenzhen. The water quality of Xikeng Reservoir has been poor, with much of the pollution coming from nonpoint sources. An innovative low impact development type of BMP called the BioBox was used at the Administration Building parking lot location, as a research site and demonstration project to show how small alterations to parking lot designs can dramatically decrease pollutant loads. Manual samples were collected during storm events and analyzed for total suspended solids (TSS); five-day biochemical oxygen demand (BOD5); ammonia nitrogen (NH3-N), and total phosphorus (TP). In summary, the ranges of removal rates of the BioBox are: TSS 70% - 90%; BOD5 20% - 50%, and ammonia and phosphorus 30% - 70%. The BioBox system effectively reduced the concentrations of pollutants in the parking lot runoff.

Hydraulic and treatment performance of pervious pavements under variable drying and wetting regimes

2011 ◽  
Vol 64 (8) ◽  
pp. 1692-1699 ◽  
Author(s):  
C. F. Yong ◽  
A. Deletic ◽  
T. D. Fletcher ◽  
M. R. Grace
Keyword(s):  
Suspended Solids ◽  
High Flow ◽  
Pollutant Removal ◽  
Low Flow ◽  
Storm Event ◽  
Stormwater Treatment ◽  
Storm Events ◽  
Treatment Technology ◽  
Porous Asphalt ◽  
Treatment Performance

Pervious pavements are an effective stormwater treatment technology. However, their performance under variable drying and wetting conditions have yet to be tested, particularly under a continuous time scale. This paper reports on the clogging behaviour and pollutant removal efficiency of three pervious pavement types over 26 accelerated years. These pavements were monolithic porous asphalt (PA), Permapave (PP) and modular Hydrapave (HP). Over a cycle of 13 days, the period of which was equivalent to the average annual Brisbane, Australia rainfall (1,200 mm), the pavements were randomly dosed with four different flows. Drying events of 3 h duration were simulated during each flow. Inflow and outflow samples were collected and analysed for Total Suspended Solids (TSS), Total Phosphorus (TP) and Total Nitrogen (TN). To evaluate the rate of clogging, a 1 in 5 year Brisbane storm event was simulated in the 6th, 8th, 12th, 16th, 20th and 24th week. Under normal dosing conditions, none of the pavements showed signs of clogging even after 15 years. However, under storm conditions, both PA and HP started to clog after 12 years, while PP showed no signs of clogging after 26 years. The drying and various flow events showed no effects in TSS removal, with all systems achieving a removal of approximately 100%. The average TP removal was 20% for all flows except for low flow, which had a significant amount of leaching over time. Leaching from TN was also observed during all flows except high flow. The TSS, TP and TN results observed during storm events were similar to that of high flow.

scholarly journals Speciation of riverine particulate phosphorus during rain events

1999 ◽  
Vol 47 (1) ◽  
pp. 87-109 ◽  
Author(s):  
Nic Pacini ◽  
Ren� G�chter
Keyword(s):  
Particulate Phosphorus ◽  
Rain Events
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