Restructuring of Backrest and Drainage Provision System in the Campus Area

2021 ◽  
Vol 6 (4) ◽  
pp. 16-21
Author(s):  
Ofik T. Purwadi ◽  
L. Afriani ◽  
A. Zakaria

The University of Lampung area, especially in the Faculty of ISIP, FEB, and FT is a densely packed student area. This area has undergone many land-use changes. The condition of the land as a green open space has changed its function to become an area for lecture buildings and offices. One of the impacts is an increase in direct surface runoff and a decrease in the quantity of water that seeps into the ground, this condition causes flooding during the rainy season. To facilitate the rehabilitation of the drainage system in the University of Lampung area, it is necessary to redesign the drainage system of the University of Lampung area. Rehabilitation of drainage channels is carried out to resolve flood inundation points that occur during the rainy season. Rainwater that is channeled through drainage channels is directed to natural or artificial reservoirs. The collected rainwater is used to recharge groundwater through natural infiltration methods. The analysis carried out in this study includes hydrological analysis and analysis of the existing drainage sections and the solutions are given. The hydrological analysis aims to calculate the planned discharge using the rational method. Modeling with the application used in this study aims to determine the capacity of the water level in the existing channel. Based on the results of the analysis, in the area, the Faculty of Engineering experienced runoff and inundation. This situation requires rehabilitation of the Lampung University area drainage system.

2004 ◽  
Vol 8 (5) ◽  
pp. 903-922 ◽  
Author(s):  
M. Bari ◽  
K. R. J. Smettem

Abstract. A conceptual water balance model is presented to represent changes in monthly water balance following land use changes. Monthly rainfall–runoff, groundwater and soil moisture data from four experimental catchments in Western Australia have been analysed. Two of these catchments, "Ernies" (control, fully forested) and "Lemon" (54% cleared) are in a zone of mean annual rainfall of 725 mm, while "Salmon" (control, fully forested) and "Wights" (100% cleared) are in a zone with mean annual rainfall of 1125 mm. At the Salmon forested control catchment, streamflow comprises surface runoff, base flow and interflow components. In the Wights catchment, cleared of native forest for pasture development, all three components increased, groundwater levels rose significantly and stream zone saturated area increased from 1% to 15% of the catchment area. It took seven years after clearing for the rainfall–runoff generation process to stabilise in 1984. At the Ernies forested control catchment, the permanent groundwater system is 20 m below the stream bed and so does not contribute to streamflow. Following partial clearing of forest in the Lemon catchment, groundwater rose steadily and reached the stream bed by 1987. The streamflow increased in two phases: (i) immediately after clearing due to reduced evapotranspiration, and (ii) through an increase in the groundwater-induced stream zone saturated area after 1987. After analysing all the data available, a conceptual monthly model was created, comprising four inter-connecting stores: (i) an upper zone unsaturated store, (ii) a transient stream zone store, (ii) a lower zone unsaturated store and (iv) a saturated groundwater store. Data such as rooting depth, Leaf Area Index, soil porosity, profile thickness, depth to groundwater, stream length and surface slope were incorporated into the model as a priori defined attributes. The catchment average values for different stores were determined through matching observed and predicted monthly hydrographs. The observed and predicted monthly runoff for all catchments matched well with coefficients of determination (R2) ranging from 0.68 to 0.87. Predictions were relatively poor for: (i) the Ernies catchment (lowest rainfall, forested), and (ii) months with very high flows. Overall, the predicted mean annual streamflow was within ±8% of the observed values. Keywords: monthly streamflow, land use change, conceptual model, data-based approach, groundwater


2021 ◽  
Vol 331 ◽  
pp. 08002
Author(s):  
Rusli HAR ◽  
Aprisal ◽  
Werry Darta Taifur ◽  
Teguh Haria Aditia Putra

Changes in land use in the Air Dingin watershed (DAS) area in Padang City, Indonesia, lead to a decrease in rainwater infiltration volume to the ground. Some land use in the Latung sub-watershed decrease in infiltration capacity with an increase in surface runoff. This research aims to determine the effect of land-use changes on infiltration capacity and surface runoff. Purposive sampling method was used in this research. The infiltration capacity was measured directly in the field using a double-ring infiltrometer, and the data was processed using the Horton model. The obtained capacity was quantitatively classified using infiltration zoning. Meanwhile, the Hydrologic Engineering Center - Hydrology Modeling System with the Synthetic Unit Hydrograph- Soil Conservation Service -Curve Number method was used to analyze the runoff discharge. The results showed that from the 13 measurement points carried out, the infiltration capacity ranges from 0.082 - 0.70 cm/minute or an average of 0.398 cm/minute, while the rainwater volume is approximately 150,000 m3/hour/km2. Therefore, the soil infiltration capacity in the Latung sub-watershed is in zone VI-B or very low. This condition had an impact on changes in runoff discharge in this area, from 87.84 m3/second in 2010 to 112.8 m3/second in 2020 or a nail of 22.13%. Based on the results, it is concluded that changes in the land led to low soil infiltration capacity, thereby leading to an increase in surface runoff.


Proceedings ◽  
2020 ◽  
Vol 30 (1) ◽  
pp. 62
Author(s):  
Zahra Kalantari ◽  
Johanna Sörensen

The densification of urban areas has raised concerns over increased pluvial flooding. Flood risk in urban areas might increase under the impact of land use changes. Urbanisation involves the conversion of natural areas to impermeable areas, causing lower infiltration rates and increased runoff. When high-intensity rainfall exceeds the capacity of an urban drainage system, the runoff causes pluvial flooding in low-laying areas. In the present study, a long time series (i.e., 20 years) of geo-referenced flood claims from property owners has been collected and analysed in detail to assess flood risk as it relates to land use changes in urban areas. The flood claim data come from property owners with flood insurance that covers property loss from overland flooding, groundwater intrusion through basement walls, as well as flooding from drainage systems; these data serve as a proxy of flood severity. The spatial relationships between land use change and flood occurrences in different urban areas were analysed. Special emphasis was placed on examining how nature-based solutions and blue-green infrastructure relate to flood risk. The relationships are defined by a statistical method explaining the tendencies whereby land use change affects flood risk.


2017 ◽  
Vol 11 (2) ◽  
pp. 99-105 ◽  
Author(s):  
Idham Riyando Moe ◽  
Shuichi Kure ◽  
Nurul Fajar Januriyadi ◽  
Mohammad Farid ◽  
Keiko Udo ◽  
...  

2016 ◽  
Vol 18 (2) ◽  
pp. 95 ◽  
Author(s):  
Irmadi Nahib

<p class="JudulABSInd"><strong>ABSTRAK</strong></p><p class="abstrak">Salah satu indikator perkembangan fisik wilayah kota dapat diidentifikasi melalui fenomena perubahan tutupan lahan bervegetasi menjadi lahan terbangun. Perubahan lahan tersebut dapat berdampak terhadap penurunan kualitas lingkungan, akibat berkurangnya ruang terbuka hijau. Kota Semarang dengan visi terwujudnya Semarang sebagai kota perdagangan dan jasa yang berbudaya menuju masyarakat sejahtera, merupakan  wilayah yang rentan mengalami perubahan penggunaan lahan yang cenderung kearah lahan terbangun. Penelitian ini mengintegrasikan model <em>Cellular Automata</em> (CA) dan regresi logistik biner untuk memprediksi dinamika lahan terbangun di Kota Semarang. Citra yang digunakan adalah Citra Ikonos 2002, Ikonos 2006 dan <em>Quic</em><em>kbird</em> 2012. Model CA pada penelitian ini digunakan untuk memprediksi sebaran penutup lahan tahun 2022 dan 2032 dengan mempertimbangkan jarak terhadap jalan, jarak terhadap sungai, jarak terhadap lahan terbangun, ketinggian, kepadatan penduduk, <em>evidence likelihood </em>perubahan lahan dan indeks pengembangan kelurahan yang diakomodasi dalam peta sub-model transisi hasil model regresi logistik biner. Hasil penyusunan model ini adalah peta prediksi penutup lahan dengan akurasi 78,21 % validitas model yang dihasilkan dapat dikategorikan “<em>moderate</em>” mengindikasikan bahwa peta yang dihasilkan dapat digunakan. Hasil pemodelan menunjukkan bahwa Kota Semarang pada tahun 2022 terjadi pertambahan luas lahan terbangun rata-rata 284 ha/tahun dan pada tahun 2032 rata-rata 226 ha/tahun.</p><p><strong><em>Kata </em></strong><strong><em>k</em></strong><strong><em>unci</em></strong><em>: </em><em>cellular automata, pemodelan, regresi logistik biner, lahan terbangun</em></p><p class="judulABS"><em><strong>ABSTRACT</strong></em></p><p class="Abstrakeng">One indicator of the physical development of the city can be identified by phenomenon of land expansion, vegetated land cover changes to be built-up area. The land use changes can impact to environmental degradation, due to reduced green open space. Semarang as a city of trade and services cultured toward a prosperous community, a region that is vulnerable to changes in land use tends toward small plots. This research integrates the model of Cellular Automata (CA) and binary logistic regression to predict the dynamics of builtup area in the city of Semarang. The image used is a Ikonos imagery (2002), Ikonos imagery (2006) and Quickbird (2012). Model CA in this research use to predict the distribution of land cover 2022 and 2032 with respect to: distance to roads, the distance to the river, the distance to the built-up area, elevation, population density, evidence likelihood of land use change and development villages index were accommodated in the map sub-model transition binary logistic regression model results. The results of this study are predictive maps of built-up area  with an accuracy of 78,21 % so that the validity of the resulting model can be categorized as "moderate", indicates that the probability map is valid. Modeling results showed that Semarang City in 2022 predicted rate of increase of  built-up area an average 284  ha / year and in 2032 rate of increase of built-up area an average 226 ha / year.</p><p><strong><em>Keywords</em></strong><em>: cellular automata, modelling, binary logistic regression, built-up area</em></p>


2019 ◽  
Vol 3 (1) ◽  
pp. 49
Author(s):  
Usaamah Hadi ◽  
Entin Hidayah ◽  
Gusfan Halik

The problem of flood inundation in the Kebon Agung River at the Medokan Ayu Village, Rungkut District Surabaya, is getting worse due to the conditions of topographic, soil properties, high rainfalls, rising sea tides and very significant changes in land use. The eastern part of Surabaya, which was formerly open space land and now developed into a residential area. Therefore in the area, there is often flood inundation when the rainy season due to lack of recharge areas and poor drainage facilities. The performance evaluation of the drainage system was carried out using the SWMM program that is combining hydrology and hydraulic analysis. Hydrology analysis is used to determine various rainfall return periods. The maximum rainfall data are collected for 18 years. The hydraulic analysis is used to obtain the data in the form of cross-section, roughness, and drainage channel capacity. The results of the evaluation of drainage system modeling with SWMM have obtained the inundation points, namely for channels K3-K4-K5- K6-K7-K8 on the right side and Ki2-Ki3-Ki4-Ki5 on the left side. Pemasalahan genangan banjir di Kali Kebon Agung di Kelurahan Medokan Ayu Kecamatan Rungkut Surabaya menjadi semakin parah karena kondisi topografi, sifat tanah, tingginya intensitas hujan, meningkatnya pasang surut air laut dan perubahan tata guna lahan yang sangat signifikan. Wilayah Surabaya bagian timur yang semula lahan terbuka kini berkembang menjadi daerah perumahan. Oleh sebab itu di wilayah tersebut sering terjadi genangan banjir saat musim hujan dikarenakan kurangnya daerah resapan dan fasilitas drainase yang kurang baik. Evaluasi kinerja sistem drainase pada wilayah tersebut dilakukan dengan menggunakan pemodelan SWMM yang megabungkan pemodelan hidrologi dan hirdolika. Analisis hidrologi digunakan untuk menentukan berbagai kala ulang hujan. Data curah hujan maksimum digunakan selama 18 tahun. Analisis hidrolika digunakan untuk memperoleh data berupa penampang, kekasaran, dan kapasitas saluran drainase. Hasil running SWMM didapatkan titik titik lokasi genangan pada saluran K3-K4-K5-K6- K7-K8 pada sisi kanan dan Ki2-Ki3-Ki4-Ki5 pada sisi kiri.


2016 ◽  
Vol 11 (3) ◽  
pp. 110-125 ◽  
Author(s):  
Yan Li ◽  
Chunlu Liu

Urban flooding has been a severe problem for many cities around the world as it remains one of the greatest threats to the property and safety of human communities. In Australia, it is seen as the most expensive natural hazard. However, urban areas that are impervious to rainwater have been sharply increasing owing to booming construction activities and rapid urbanisation. The change in the built environment may cause more frequent and longer duration of flooding in floodprone urban regions. Thus, the flood inundation issue associated with the effects of land uses needs to be explored and developed. This research constructs a framework for modelling urban flood inundation. Different rainfall events are then designed for examining the impact on flash floods generated by land-use changes. Measurement is formulated for changes of topographical features over a real time series. Geographic Information System (GIS) technologies are then utilised to visualise the effects of land-use changes on flood inundation under different types of storms. Based on a community-based case study, the results reveal that the built environment leads to varying degrees of aggravation of urban flash floods with different storm events and a few rainwater storage units may slightly mitigate flooding extents under different storm conditions. Hence, it is recommended that the outcomes of this study could be applied to flood assessment measures for urban development and the attained results could be utilised in government planning to raise awareness of flood hazard.


2010 ◽  
Vol 14 (2) ◽  
pp. 291-300 ◽  
Author(s):  
N. Gratiot ◽  
C. Duvert ◽  
L. Collet ◽  
D. Vinson ◽  
J. Némery ◽  
...  

Abstract. The hydrological response of a medium scale mountainous watershed (Mexico) is analysed over half a century. The hydrograph separation highlights an increasing surface runoff contribution since the early 1970's. This increase is attributed to land use changes while the meteorological forcing (rains) remains statistically stable over the same period. As a consequence, the intensity of annual extreme floods has tripled up over the period of survey, increasing flood risks in the region. The paper ends with a climatic projection over the 21st century. The decrease of precipitation and the increase of temperature should accentuate the trend engaged since the 1970's by reducing groundwater resources and increasing surface-runoff and associated risks.


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