scholarly journals A multi-functional and multi-compartment constructed wetland to support urban waterway restoration

2018 ◽  
Vol 13 (4) ◽  
pp. 764-770 ◽  
Author(s):  
T. M. Adyel ◽  
M. R. Hipsey ◽  
C. Oldham
Keyword(s):  
Constructed Wetland ◽  
Flow System ◽  
Surface Flow ◽  
Base Flow ◽  
Low Flow ◽  
Nutrient Loads ◽  
Storm Events ◽  
Flow Conditions ◽  
Storm Flow ◽  
Diverse Area

Abstract This study assessed the significance of a multi-functional and multi-compartment constructed wetland (CW) implemented to restore a degraded urban waterway in Western Australia. The wetland was initially constructed as a surface flow system, then modified through the incorporation of the additional laterite-based subsurface flow system, with the potential for operation of a recirculation scheme and groundwater top-up during low water flows in summer. The CW performance was assessed by comparing nitrogen (N) and phosphorus (P) attenuation during base flow, high flow and episodic storm flow conditions. The performance varied from approximately 41% total nitrogen (TN) and 66% total phosphorus (TP) loads reduction during storm events, increasing up to 62% TN and 99% TP during low flow and summer recirculation periods. In overall, the CW attenuated about 45% TN and 65% TP loads from being delivered to the downstream sensitive river between 2009 and 2015. The CW design proved to be not only highly effective at reducing nutrient loads, but also improved the ecological services of the urban waterway by providing a diverse area for habitat and recreational activities.

scholarly journals Hydrology and riparian forests drive carbon and nitrogen supply and DOC:NO<sub>3<sup>−</sup></sub> stoichiometry along a headwater Mediterranean stream

2021 ◽  
Author(s):  
José L. J. Ledesma ◽  
Anna Lupon ◽  
Eugènia Martí ◽  
Susana Bernal
Keyword(s):  
Riparian Forest ◽  
Base Flow ◽  
Riparian Forests ◽  
Storm Events ◽  
Flow Conditions ◽  
Heterotrophic Activity ◽  
Molar Ratios ◽  
Mediterranean Stream ◽  
Storm Flow ◽  
Forest Coverage

Abstract. In forest headwater streams, metabolic processes are predominately heterotrophic and depend on both the availability of carbon (C) and nitrogen (N) and a favourable C:N stoichiometry. In this context, hydrological conditions and the presence of riparian forests adjacent to streams can play an important, yet understudied role determining dissolved organic carbon (DOC) and nitrate (NO3−) concentrations and DOC:NO3− molar ratios. Here, we aimed to investigate how the interplay between hydrological conditions and riparian forest coverage drives DOC and NO3− supply and DOC:NO3− stoichiometry in an oligotrophic headwater Mediterranean stream. We analysed DOC and NO3− concentrations, and DOC:NO3− molar ratios during both base flow and storm flow conditions at three stream locations along a longitudinal gradient of increased riparian forest coverage. Further, we performed an event analysis to examine the hydroclimatic conditions that favour the transfer of DOC and NO3− from riparian soils to the stream during large storms. Stream DOC and NO3− concentrations were generally low (overall average ± SD was 1.0 ± 0.6 mg C L−1 and 0.20 ± 0.09 mg N L−1), although significantly higher during storm flow compared to base flow conditions in all three stream sites. Optimal DOC:NO3− stoichiometry for stream heterotrophic microorganisms (corresponding to DOC:NO3− molar ratios between 4.8 and 11.7) was prevalent at the midstream and downstream sites under both flow conditions, whereas C-limited conditions were prevalent at the upstream site, which had no surrounding riparian forest. The hydroclimatic analysis of large storm events highlighted different patterns of DOC and NO3− mobilization depending on antecedent soil moisture conditions: drier antecedent conditions promoted rapid elevations of riparian groundwater tables, hydrologically activating a wider and shallower soil layer, and leading to relatively higher increases in stream DOC and NO3− concentrations compared to events preceded by wet conditions. These results suggest that (i) increased supply of limited resources during storms can promote in-stream heterotrophic activity during high flows, especially during large storm events preceded by dry conditions, and (ii) C-limited conditions upstream were gradually overcome downstream, likely due to higher C inputs from riparian forests present at lower elevations. The contrasting spatiotemporal patterns in DOC and NO3− availability and DOC:NO3− stoichiometry observed at the study stream suggests that groundwater inputs from riparian forests are essential for maintaining in-stream heterotrophic activity in oligotrophic, forest headwater catchments.

scholarly journals Forecasting Low Stream Flow Rate Using Monte—Carlo Simulation of Perigiali Stream, Kavala City, NE Greece

Proceedings ◽  
2018 ◽  
Vol 2 (11) ◽  
pp. 580 ◽  
Author(s):  
Thomas Papalaskaris ◽  
Theologos Panagiotidis
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Flow Rate ◽  
Stream Flow ◽  
Simulation Method ◽  
Base Flow ◽  
Low Flow ◽  
Rate Data ◽  
Storm Flow ◽  
Management Plans

A small number of scientific research studies with reference to extremely low flow conditions, have been conducted in Greece, so far. Predicting future low stream flow rate values is an essential and of paramount importance task when compiling watershed and drought management plans, designing water reservoirs and general hydraulic works capacity, calculating hydrological and drought low flow values, separating groundwater base flow and storm flow of storm hydrographs etc. The Monte-Carlo simulation method generates multiple attempts to define the anticipated value of a random (hydrological in this specific case) variable. The present study compiles, correspondingly, artificial low stream flow time series of both the same part of the year (2016) as well as a part of the calendar year (2017), based on the stream flow data observed during the same two different interval periods of the years 2016 and 2017, using a 3-inches U.S.G.S. modified portable Parshall flume, a 3-inches conventional portable Parshall flume, a 3-inches portable Montana (short Parshall) flume and a 90° V-notched triangular shaped sharp crested portable weir plate. The recorded data were plotted against the fitted one and the results were demonstrated through interactive tables providing us the ability to effectively evaluate the simulation procedure performance. Finally, we plot the observed against the calculated low stream flow rate data, compiling a log-log scale chart which provides a better visualization of the discrepancy ratio statistical performance metric and calculate statistics featuring the comparison between the recorded and the forecasted low stream flow rate data.

Effect of recirculation on organic matter removal in a hybrid constructed wetland system

2011 ◽  
Vol 63 (10) ◽  
pp. 2360-2366 ◽  
Author(s):  
S. Ç. Ayaz ◽  
N. Findik ◽  
L. Akça ◽  
N. Erdoğan ◽  
C. Kınacı
Keyword(s):  
Organic Matter ◽  
Constructed Wetland ◽  
Suspended Solids ◽  
Flow System ◽  
Pilot Scale ◽  
Surface Flow ◽  
Small Communities ◽  
Anaerobic Reactors ◽  
Wetland System ◽  
Anaerobic Pretreatment

This research project aimed to determine the technologically feasible and applicable wastewater treatment systems which will be constructed to solve environmental problems caused by small communities in Turkey. Pilot-scale treatment of a small community's wastewater was performed over a period of more than 2 years in order to show applicability of these systems. The present study involves removal of organic matter and suspended solids in serially operated horizontal (HFCW) and vertical (VFCW) sub-surface flow constructed wetlands. The pilot-scale wetland was constructed downstream of anaerobic reactors at the campus of TUBITAK-MRC. Anaerobically pretreated wastewater was introduced into this hybrid two-stage sub-surface flow wetland system (TSCW). Wastewater was first introduced into the horizontal sub-surface flow system and then the vertical flow system before being discharged. Recirculation of the effluent was tested in the system. When the recirculation ratio was 100%, average removal efficiencies for TSCW were 91 ± 4% for COD, 83 ± 10% for BOD and 96 ± 3% for suspended solids with average effluent concentrations of 9 ± 5 mg/L COD, 6 ± 3 mg/L BOD and 1 mg/L for suspended solids. Comparing non-recirculation and recirculation periods, the lowest effluent concentrations were obtained with a 100% recirculation ratio. The effluent concentrations met the Turkish regulations for discharge limits of COD, BOD and TSS in each case. The study showed that a hybrid constructed wetland system with recirculation is a very effective method of obtaining very low effluent organic matter and suspended solids concentrations downstream of anaerobic pretreatment of domestic wastewaters in small communities.

Analysis of parameter variations in L–Q equations for river runoff processes from the viewpoint of spatial and temporal conditions

2006 ◽  
Vol 53 (10) ◽  
pp. 141-152 ◽  
Author(s):  
S. Fujii ◽  
B.R. Shivakoti ◽  
K. Shichi ◽  
P. Songprasert ◽  
H. Ihara ◽  
...  
Keyword(s):  
Continuous Monitoring ◽  
Base Flow ◽  
Storm Event ◽  
Storm Events ◽  
Flow Conditions ◽  
Regional Effect ◽  
Run Off ◽  
Parameter Variations ◽  
Variation Characteristics ◽  
Temporal Flow

This study aims to find out variation characteristics of the parameters of ‘a’ and ‘b’ in L=a ·Qb, an empirical equation for run-off loading (L) and flow rate (Q), by evaluating the effects of flow conditions and regional properties of the watersheds on the values. We selected the Kamo River basin (155 km2) as a study field, and conducted various kinds of investigations, such as 80 day high frequency observations, continuous monitoring for more than 2 years, storm event surveys, and simultaneous surveys of 39 stations. Then, we obtained 7–170 data in each of 39 sampling stations. The main results obtained are as follows: 1) L–Q equation with a range of ‘a’ can express L–Q relation in most of the WQIs (water quality indices); 2) ‘a’ receives temporal (flow condition) effects more in SS, VSS and Al, while it receives regional effect more in inorganic carbon, TN, Ca and Fe; 3) both of flow change in storm events, and base flow levels affect the L–Q relation, and their effects can classify the WQIs into several groups; 4) the effects of regional properties were obviously observed in ‘a’, and quantitatively evaluated, especially for density of population.

scholarly journals Determination of Tank Model Parameters with Four Series Structure in Rokan Watershed

2019 ◽  
Vol 5 (2) ◽  
pp. 85-92
Author(s):  
Manyuk Fauzi ◽  
Yohanna Lilis Handayani ◽  
Annisa Destiany
Keyword(s):  
Water Resources ◽  
Water Availability ◽  
Flow Analysis ◽  
Daily Rainfall ◽  
Surface Flow ◽  
Base Flow ◽  
Low Flow ◽  
Model Parameters ◽  
Tank Model ◽  
Discharge Data

Information about low flow and water availability is one of the important factors in the management of water resources. The Rokan River Basin as one of the water resources in Riau Province is very important to know the condition of its water availability. One conceptual hydrological model for low flow analysis is the Tank Model developed by Sugawara. Data input needed in this research is daily rainfall data at Pasar Tangun Station, climatology data at Rambah Utama station and discharge data at AWLR Pasir Pengaraian. Model parameter search in the calibration stage is by trial and error. Using a 90% confidence interval a range of parameter values for the tank model is obtained, which is special for production store are surface flow 150.81 mm ≤ H1 ≤ 204.75 mm, intermediate flow 156.74 mm ≤ H2 ≤ 194.37 mm, sub base flow 141.24 mm ≤ H3 ≤ 176, 54 mm and base flow 139.43 mm ≤ H4 ≤ 176.12 mm.

System design and treatment efficiency of a surface flow constructed wetland receiving runoff impacted stream water

2012 ◽  
Vol 65 (3) ◽  
pp. 525-532 ◽  
Author(s):  
M. C. Maniquiz ◽  
J. Y. Choi ◽  
S. Y. Lee ◽  
C. G. Kang ◽  
G. S. Yi ◽  
...  
Keyword(s):  
Water Quality ◽  
Constructed Wetland ◽  
Stream Water ◽  
Free Water ◽  
Potential Effect ◽  
Surface Flow ◽  
Agricultural Watershed ◽  
Initial Time ◽  
Storm Events ◽  
Pollutant Concentrations

This study reported the efficiency of a free water surface flow constructed wetland (CW) system that receives runoff impacted stream water from a forested and agricultural watershed. Investigations were conducted to examine the potential effect of hydraulic fluctuations on the CW as a result of storm events and the changes in water quality along the flow path of the CW. Based on the results, the incoming pollutant concentrations were increased during storm events and greater at the near end of the storm than at the initial time of storm. A similar trend was observed to the concentrations exiting the CW due to the wetland being a relatively small percentage of the watershed (&lt;0.1%) that allowed delays in runoff time during storm events. The concentrations of most pollutants were significantly reduced (p &lt; 0.05) except for nitrate (p = 0.5). Overall, this study suggests that the design of the system could feasibly function for the retention of most pollutants during storm events as the actual water quality of the outflow was significantly better by 21–71% than the inflow and the levels of pollutants were reduced to appreciable levels.

Effects of Urbanization on Stream Ecosystems

2005 ◽  
Keyword(s):  
Water Quality ◽  
Suspended Sediment ◽  
Brown Trout ◽  
Dose Response ◽  
Quality Criteria ◽  
Base Flow ◽  
Response Model ◽  
Storm Events ◽  
Flow Conditions ◽  
Blood Samples

<em>Abstract.</em>—Urban streams typically have increased flows, high suspended sediment concentrations, and reduced water quality during rainstorms as a result of changes within the watershed related to human activity. In the 6-month periods from May through October of 2001 and 2002, water quality was monitored continuously at five sites along Rapid Creek within Rapid City, South Dakota. Water quality samples were collected for eight base flows (nonevents) and eight storm events. Blood samples were collected from wild adult brown trout <em>Salmo trutta </em>during base flow conditions and six of eight storm events to determine if storm events could elicit physiological stress responses. Blood samples were also collected 24, 48, and 96 h after each storm event had started. Water monitoring results showed significant increases in runoff volume and peak flows during storm events. Water quality parameters exceeding South Dakota’s water quality criteria for a coldwater fishery were total suspended solids and temperature. Plasma concentrations of cortisol and lactate, during and after storm events, were not significantly different than those measured during base flow conditions. Plasma glucose values were lower during storm events than during nonevent periods. These observations were compared to those predicted by a suspended sediment dose–response model developed for adult salmonids. The dose–response model overpredicted the severity of the effects of increased total suspended sediment on the brown trout during stormwater runoff events.

scholarly journals An evaluation of image velocimetry techniques under low flow conditions and high seeding densities using Unmanned Aerial Systems

2020 ◽  
Author(s):  
Sophie Pearce ◽  
Robert Ljubicic ◽  
Salvador Pena-Haro ◽  
Matthew Perks ◽  
Flavia Tauro ◽  
...  
Keyword(s):  
Feature Extraction ◽  
Large Scale ◽  
Surface Flow ◽  
Extraction Rate ◽  
Particle Identification ◽  
Surface Velocity ◽  
Low Flow ◽  
Unmanned Aerial Systems ◽  
Flow Conditions ◽  
Image Velocimetry

&lt;p&gt;Image velocimetry (IV) is a remote technique which calculates surface flow velocities of rivers (or fluids) via a range of cross-correlation and tracking algorithms. IV can be implemented via a range of camera sensors which can be mounted on tri-pods, or Unmanned Aerial Systems (UAS). IV has proven a powerful technique for monitoring river flows during flood conditions, whereby traditional in-situ techniques would be unsafe to deploy. However, little research has focussed upon the application of such techniques during low flow conditions. The applicability of IV to low flow studies could aid data collection at a higher spatial and temporal resolution than is currently available. Many IV techniques are under-development, that utilise different cross-correlation and tracking algorithms, including, Large Scale Particle Image Velocimetry (LSPIV), Large Scale Particle Tracking Velocimetry (LSPTV), Optical Tracking Velocimetry (OTV), Kanade Lucas Tomasi Image Velocimetry (KLT-IV) and Surface Structure Image Velocimetry (SSIV). Nevertheless, the true applications and limitations of such algorithms have yet to be extensively tested. Therefore, this study aimed to conduct a sensitivity analysis on the commonly relatable parameters between the different algorithms, including the particle identification area parameters (such as Interrogation Area (LSPIV, LSPTV and SSIV), Block Size (KLT-IV) and Trajectory Length (OTV)) and the feature extraction rate (or sub sampled frame rate).&lt;/p&gt;&lt;p&gt;Fieldwork was carried out on Kolubara River near the city of Obrenovac in Central Serbia. Cross-sectional surface width was relatively constant, varying between 23.30 and 23.45m. During the experiment, low flow conditions were present with a discharge of approx. 3.4m&lt;sup&gt;3 &lt;/sup&gt;s&lt;sup&gt;-1&lt;/sup&gt; (estimated using a Sontek M9 ADCP), and depths of up to 1.9m. A DJI Phantom 4 Pro UAS was used to collect video data of the surface flow. Artificial seeding material (wood-mulch) was distributed homogenously across the rivers&amp;#8217; surface, in order to improve the conditions for IV techniques during slow flows. Two 30-second videos were utilised for surface velocity analysis.&lt;/p&gt;&lt;p&gt;This study highlighted that KLT, SSIV, OTV and LSPIV are the least sensitive algorithms to changing parameters when no pre- or post-processing of results are conducted. On the other hand, LSPTV must undergo post-processing procedures in order to avoid spurious results and only then, results may be reliable. Furthermore, KLT and SSIV highlighted a slight sensitivity to changing the feature extraction rate, however changing the particle identification area did not affect significantly the outputted surface velocity results. OTV and LSPTV, on the other hand, highlighted that changing the particle identification area provided a higher variability in the results, whilst changing the feature extraction rate did not affect the surface velocity outputs. LSPIV proved to be sensitive to changing both the feature extraction rate and the particle identification area.&lt;/p&gt;&lt;p&gt;This analysis has led to the conclusions that during the conditions of sampling with surface velocities of approximately 0.12ms&lt;sup&gt;-1&lt;/sup&gt;, and homogeneous seeding on the rivers surface, IV techniques can provide results comparable to traditional techniques such as ADCPs during low flow conditions. All IV algorithms provided results that were, on average, within 0.05ms&lt;sup&gt;-1&lt;/sup&gt; of the ADCP measurements.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;

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