• Journal of Korean Society of Environmental Engineers
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• v.33 no.4
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• pp.289-299
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• 2011

We studied the characteristics of pollutant concentrations in 9 streams that flow into Shihwa Lake in order to provide the scientific data for effective implementation of total pollution loads management system (TPLMS) of the Lake. Suspended solid (SS), chemical oxygen demand (COD), dissolved nutrients ($NO_2$, $NO_3$, $NH_4$, $PO_4$ and $SiO_2$), total phosphorus (TP) and total nitrogen (TN) in stream water from industrial complexes, urban and agricultural regions were determined. Pollutant concentrations in December were higher than that in other sampling periods. COD concentration from industrial complex region with average of 12.6 mg/L was 2 times higher those from urban region (6.6 mg/L) and agricultural region (5.9 mg/L). TP concentration from industrial region also showed higher concentration than other regions. TN concentration in stream water was 5.89 mg/L for industrial region, 3.02 mg/L for urban region and 5.27 mg/L for agricultural region, respectively, suggesting inflow of TN due to fertilizer usage in agricultural field. Relative percentage of nitrogen compounds in TN follows the sequence: $NH_4$ (35.1%) > $NO_2$ (20.0%) > DON (22.8%) > PON (8.9%) > $NO_2$ (3.2%). Concentrations of dissolved nutrients, TP and TN in stream water were 3.2~37.2 times higher than that in Shihwa Lake seawater, therefore large amount of pollutants may be directly entered into Shihwa Lake without any treatment. For Gunja stream of industrial region, pollutants at midstream showed relatively higher concentration compared to upstream and downstream. It is necessary to manage the illegal discharging of sewage and waste water. Our results provide valuable informations on the estimation and reduction of total pollutant loads in the process of establishing adequately strategic and implemental plan of Shihwa Lake TPLMS.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.975-982
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• 2009

The purpose of this study is to offer informations about the current conditions and basic data of stream sediments in Busan city. So we first select 14 urban streams and collect sediment samples. Then, COD, proximate analysis, volatile solid, organic carbon content and elemental analysis were conducted to determine characteristics of the sediments. Results show that COD, volatile solid, Organic carbon content, T-N of sediment are determined in the range of 1.20~75.07 mg/g, 0.19~11.54%, 0.23~34.21% and 0.76~3.46%, respectively. Analysis data of sediments were compared with USEPA sediment quality standards and ontario sediment quality guidelines. As a result, when compared with COD, volatile solid and organic carbon content values, Bosucheon and Gudeokcheon are relatively heavily contaminated than the remainder sampling sites. But when compared with T-N values, all of sites were evaluated as seriously contaminated. Finally, for the determination of the correlations between sediment COD and moisture contents, ash contents, volatile solid, total organic carbon, total nitrogen and total carbon, linear model was fitted to the data using a least-squares algorithm. As a result, Linear model was well fitted to each data with good values of the correlation coefficient (r=0.9664~0.8501).

• Journal of Wetlands Research
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• v.20 no.1
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• pp.35-42
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• 2018

This study presents the flow response and habitat region of the aquatic plants in the urban streams. Phragmites japonica, Phragmites communis, Miscanthus sacchariflorus, Persicaria blumei and Persicaria thunbergii were selected as for typical plants. Flow response and habitat region were determined by flow velocity/depth and vegetation growth. Stages for flow response of the aquatic plants were classified into stable, recovered, damaged and swept away. Criteria between the recovered and damaged stage was determined by the bending angle of $30{\sim}50^{\circ}$. Capability against flow was high in the order of Phragmites japonica, Phragmites communis, Miscanthus sacchariflorus, Persicaria blumei and Persicaria thunbergi. Phragmites japonica and Phragmites communis were capable of coping with flow depth 0.9 m, flow velocity 1.5 m/s and with flow depth 1.0 m, flow velocity 0.9 m/s, respectively. Miscanthus sacchariflorus was capable within the region of flow depth 1.0 m and flow velocity 0.6 m/s. Persicaria blumei and Persicaria thunbergii were less capable than the other aquatic plants and were vulnerable exceeding the water depth of 1.0 m. Habitat regions by the flow response of each plants were suggested.

• Korean Journal of Ecology and Environment
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• v.57 no.1
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• pp.17-27
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• 2024

This study investigated the fish fauna of Jeonjucheon and Samcheon Streams, flowing through the city of Jeonju, through surveys conducted at 10 sampling sites using kick net and cast net. The fish fauna collected included 10 families and 36 species, with a total of 2,064 individuals. Samcheon had 8 families and 30 species with 1,074 individuals, Jeonjucheon had 8 families and 26 species with 986 individuals. The dominant species was Zacco platypus with 1,202 individuals, and a total of 153 individuals of the subdominant were Pseudogobio esocinus. In Jeonjucheon Stream, a total of 567 individuals of the dominant species were collected as Z. platypus and 99 individuals of the subdominant species were collected as Pungtungia herzi, and there was no significant change in the stream environment except for the confluence site. Further expanded research covering the entire Jeonjucheon and Samcheon Streams region, accompanied by regular monitoring, is essential to record and understand fluctuations in fish fauna.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.2
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• pp.1-20
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• 2024

The present study was conducted to assess the adequacy of landscaping plants in city streams by investigating the species and growth status of landscaping plants, taking Godeokcheon in Seoul Metropolitan City as an example. The stream structure related to the planting ground and the impact of flood damage were analyzed. The adequacy of the planting species was analyzed based on the native species and moist land-inhabiting plants presented in the preceding study results. The adequacy, depending on the planting location and planting form, was analyzed using the growth states of adaptive and nonadaptive species by river topography. The planting location of those along the waterfront was the best, followed by the plants on waterside hills and embankment slopes. It is thought that the adaptability of dryland-inhabiting plants increased as the soil dried due to the impervious pavement of surrounding bikeways and trails. The species adequate for embankment slopes are thought to be native species and dryland-inhabiting plants. It is thought that, for waterside hills, the planting rate of wetland-inhabiting plants should be increased, and for waterfronts, the planting rate of dryland-inhabiting plants should be decreased. As for the planting form, the growth state was the best when mixed species were planted and the worst when other plants appeared. For city streams, the planting rates of native species and wetland-inhabiting plants should be increased, and adequate plant species for each location should be selected.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1433-1446
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• 2013

In this study, we proposed a methodology to develop Rating Curves for high water level using rainfall generation by the Monte Carlo Simulation (MCS) technique, optimized rainfall-runoff model, and flood routing model in an urban stream. The developed stage discharge Rating Curve based on observed data was contained flow measurement errors and uncertainties. The standard error ($S_e$) for observations was 0.056, and the random uncertainty ($2S_{mr}$) was analyzed by ${\pm}1.43%$ on average, and up to ${\pm}4.27%$. Moreover, it was found that the Rating Curve extensions by way of logarithmic and Stevens methods were overestimated to compare with the urban basin scale. Finally, we confirmed that the high water level extension by random generation of hydrological data using MCS can be reduced uncertainty of the high water level, and it will consider as a more reliable approach for high water level extension. In the near future, this results can be applied to real-time flood alert system for urban streams through construction of the high water level extension system using MCS procedures.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.261-268
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• 2018

The study used the simplified flooding analysis model, SIMOD, to distribute the total flood discharge by time, so research on flooding in urban areas can be conducted. The conventional flooding analysis models have limitations in constructing input data and take a long time for analysis. However, SIMOD is useful because it supports rapid decision-making process using quick modeling based on simple hydrological data, such as topography and inflow flood of the study area, to analyze submerged routes formed by flooding. Therefore, the study used the SIMOD model to analyze flooding in urban areas before conducting a comparative study with the outputs from FLO-2D, which is one of the conventional flooding analysis models, to identify the model's applicability. Seongseoje was selected as the study area, as it is located downstream the Geumho river where streams flow in the adjacent areas, and dikes are high enough to apply the "Overflow and Break" scenario for urban areas. With regard to topography, the study applied DEM data for the conventional flooding analysis and DSM data to represent urban building communities, distribution of roads, etc. Input flood discharge was calculated by applying the rectangular weir equation under the bank and break scenario through a 200-year return period of a design flood level. Comparative analysis was conducted in a flooded area with a simulation time of 1-24 hours. The time for the 24-hour simulation in SIMOD was less than 7 minutes. Compared with FLO-2D, the difference in flooded areas was less than 20%. Furthermore, the study identified the need for topography data using DSM for urban areas, as the analysis result that applies DSM showed the influence of roads and buildings.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.2
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• pp.62-73
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• 2001

The riparian environments of urban streams in Korea have been disturbed through the channelization for flood control and artificial land use as well as water pollution and flow decrease due to industrialization and urbanization. The flora and vegetation structure were investigated and an implication of stream restoration was discussed for the conservation of biodiversity in the riparian area of the Seunggi stream in Incheon. Naturalized plants and ruderal plants were widely distributed in the riparian area which was disturbed from cultivating, trampling, dumping etc. Submerged and floating hydrophytes were not found in the stream due to channelization and water pollution. Some halophytes were remained in downstream and reservoir after reclamation and embankment. The communities of Humulus japonicus, Panicum dichotomiflorum, Digitaria sanguinalis, Artemisia montana, Amaranthus retroflexus, and Aster pilosus were distributed in the disturbed area of bank slope and floodplain in the stream. As a natural potential vegetation, Phragmites australis in the wet meadow, Typha latifolia, Typha angustifolia, Oenanthe javanica, Persicaria thunbergii, and Penthorum chinense in the marsh, and Salix babylonica and Salix matsudana for. tortuosa in the woodland appeared in the floodplain. The topography in the stream played an important role on the distribution of riparian vegetation in the Seunggi stream. Appropriate methods for conservation and restoration of the riparian ecosystems must be planned on the basis of the actual vegetation in the disturbed urban stream.

• Journal of Environmental Impact Assessment
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• v.16 no.1
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• pp.59-68
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• 2007

Urban streams have been severely degraded with wastewater and concrete structure over a prolonged period. The Chonggyecheon Restoration Project recovered a stream in the downtown Seoul with landscaping, plantings and bridges after the cover concrete and elevated asphalt road were removed. The project has been criticized partly because it is not an ecological restoration but rather the development of an urban park with an unnaturally straight flowing stream, artificial building structures, and artificial water pumping from the Han River. Nevertheless, the public have praised the project and almost 100,000 visitors per day come to see the reeds, catfish, and ducks. The stream restoration project is attractive to central and regional government decision makers because it increases the public concern of landscape amenity. Several projects such as Sanjichon and Kaeumjungchon are on going and proposed. These projects have a common and different respect in scope and procedure. The Chonggyecheon project in the process of environmental impact assessment (EIA) and prior environmental review system (PERS) reviewed the environmental impacts before development. Kaeumjungchon in the PERS and Sanjichon without EIA and PERS are reviewed. EIA and PERS systems contribute to checking the ecological sustainability of the restoration projects. A stream restoration project is a very complex task, so an integrated approach from plan to project is needed for ecologically sound restoration. Ecological stream restoration requires 1) an assessment of the entire stream ecosystem 2) establishing an ecologically sound management system of the stream reflecting not only benefits for people but also flora and fauna; 3) developing the site-specific design criteria and construction techniques including habitat restoration, flood plains conservation, and fluvial management; 4) considering the stream watershed in land use plan, EIA, PERS, and strategic environmental assessment (SEA). Additionally the process needs to develop the methodologies to enhance stakeholder's participation during planning, construction, and monitoring.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.2
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• pp.1-12
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• 2017

This study aims to provide the basic habitat data for the alternative breeding sites of Family Ardeidae including Ardea cinerea, Egretta alba modesta, Egretta intermedia, Egretta garzetta, Bubulcus ibis and Nycticorax nyciticorax. Species numbers, flight directions for detecting foraging grounds and current vegetation structure were investigated nesting at Gunsan urban forest area. Data were collected over a period of 10 weeks, from 15 June - 31 August 2014. The total nest and population of Family Ardeida were 684 and 1,712 respectively. Percentage of birds observed flying in 8 major compass directions were as follows. 57.27% of all birds were observed flying northwest, 22.09% were observed flying south and 13.40% were flying north. For possible foraging areas, to the northwest, there are Geumgang river tidal flats, and to the south, paddy fields and streams within 2km. Flying directions by species (${\chi}^2=287.18$, P<.001, Cramer's V=0.12) and by seasons(${\chi}^2=839.94$, P<.001, Cramer's V=0.19) showed significant difference statistically. In relation between species and directions, 60.31% and 24.05% of Bubulcus ibis and 59.40% and 23.00% of Ardea cinerea were observed flying northwest and south respectively. Vegetation in the sites consist of an overstory of 3 to 7 species. At site 1, Pinus thunbergii was the dominant species and site 2, Chamaecyparis obtusa. Understory vegetation is composed of shrubs, saplings and small trees of Chamaecyparis obtusa, Quercus acutissima, Smilax china and Platycarya strobilacea. Egrets and herons usually nested at the dense population and canopy overlayed forest, and especially branches and leaves of smallwood with less than 10cm of breast height diameter were relatively severely damaged due to the nesting and excreta.