JURNAL TEKNIK HIDRAULIK最新文献

{"title":"STUDY ON FLOOD CONTROL OF THE CILEUWIBANGKE RIVER DUE TO RESIDENTIAL AREA DEVELOPMENT IN BOGOR CITY, WEST JAVA","authors":"D. Yudianto, Finna Fitriana, Albert Wicaksono, Theo Senjaya","doi":"10.32679/jth.v14i2.741","DOIUrl":"https://doi.org/10.32679/jth.v14i2.741","url":null,"abstract":"ABSTRACTBogor City, renowned for its high rainfall value, has experienced rapid economic growth, leading to a substantial surge in population. This, in turn, has prompted extensive development, disrupting land use in the urban area. Consequently, effective area planning incorporating an adequate drainage system is imperative to mitigate flooding. The Cileuwibangke River, located south of Bogor City, traverses a residential area earmarked for conversion into commercial and industrial zones. Therefore, evaluating the floodwater level of the Cileuwibangke River is crucial, both in its existing state and post-construction. This study utilized daily data from the Gadog Rainfall Station and hourly data from the GPM satellite spanning from 2001 to 2020 for rainfall analysis. It revealed that several rain events exceeded the 2, 5, and 10-year return periods. Rainfall-runoff analysis showed that changes in land use resulted in a 35-36% increase in peak flood discharge and a 22-28% increase in runoff volume compared to the existing condition. The findings indicated that the normalization of the river section on the residential area side did not significantly lower the floodwater level, attributed to three broad-dimension culverts. Moreover, strengthening the river's bottom and banks is essential due to the observed hydraulic jump indication. Upstream riverbed protection can be achieved with a 35 m stretch of rock material. Keywords:       Bogor City, Cileuwibangke River, HEC-HMS, HEC-RAS, and Urban Flood ABSTRAKKota Bogor, dikenal dengan curah hujannya yang tinggi, mengalami pertumbuhan ekonomi yang tinggi sehingga menyebabkan peningkatan jumlah penduduk yang cukup pesat. Hal ini memicu pembangunan besar-besaran yang mengubah fungsi lahan di kawasan perkotaan. Oleh karena itu, perencanaan kawasan dengan sistem drainase yang memadai diperlukan untuk mencegah terjadinya banjir. Sungai Cileuwibangke, yang terletak di selatan Kota Bogor, mengalir melalui kawasan pemukiman yang akan dikembangkan menjadi kawasan komersial dan industri. Sehingga, perlu dilakukan evaluasi tinggi muka air banjir Sungai Cileuwibangke baik pada kondisi eksisting maupun setelah konstruksi. Studi ini menggunakan data harian Pos Hujan Gadog dan data jam-jaman satelit GPM dari tahun 2001 hingga 2020 untuk melakukan analisis curah hujan. Ditemukan bahwa beberapa kejadian hujan memiliki nilai lebih besar dari hujan rencana periode ulang 2, 5, dan 10 tahun. Berdasarkan analisis curah hujan-limpasan yang dilakukan, diketahui bahwa alih fungsi lahan mengakibatkan peningkatan debit banjir puncak dan volume limpasan masing-masing sebesar 35-36% dan 22-28% dibandingkan dengan kondisi eksisting. Hasil penelitian menunjukkan bahwa normalisasi ruas sungai di sisi pemukiman tidak menurunkan debit banjir secara signifikan, dikarenakan adanya tiga gorong-gorong berdimensi lebar pada kawasan tersebut. Selain itu, perlu dilakukan perkuatan dasar sungai dan bantaran sungai dikarenakan adanya indikasi lon","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":"86 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139202211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EFFORTS TO OPTIMIZE THE OPERATION OF THE DADAHUP LOWLAND IRRIGATION AREA IN CENTRAL KALIMANTAN","authors":"A. Zevri, A. P. Rahardjo, D. Legono","doi":"10.32679/jth.v14i2.726","DOIUrl":"https://doi.org/10.32679/jth.v14i2.726","url":null,"abstract":"ABSTRACT Dadahup lowland irrigation area is one of the areas developed as a food estate. Land cover change to shrubs is caused by channels with buildings that are not functioning optimally, so it is often hit by floods and droughts. One of the efforts to improve the function of channels and buildings is to control the minimum water level of 60 cm in the dry season and the maximum water level of 10 cm in the rainy season. This study aims to determine the optimal operations and maintenance through adjusting the elevation of the gate opening to achieve the quantity and quality for the development of water management systems in lowland irrigation. The research method was carried out with hydraulic simulation based on the tides of the Barito River Mouth, discharge, rainfall, and pH obtained from telemetry monitoring system with openings of all sluice gates in primary channels and secondary channels. The results showed that operation and maintenance optimization can be done by setting primary and secondary sluice gates that are opened at a water level elevation above + 0.5 m in the dry season as supply and water level elevation + 1.1 m in the rainy season as drainage. Primary and secondary sluice gates are closed at water levels below + 0.5 m to maintain water levels and water quality.Keywords        optimization, lowland, Dadahup Lowland Irrigation Area , HEC-RAS, hydraulic ABSTRAKDaerah irigasi rawa Dadahup merupakan salah satu daerah yang dikembangkan sebagai lumbung pangan. Perubahan tutupan lahan menjadi semak belukar disebabkan oleh saluran dengan bangunan yang tidak berfungsi secara optimal sehingga sering dilanda banjir dan kekeringan. Salah satu upaya untuk meningkatkan fungsi saluran dan bangunan adalah dengan mengendalikan tinggi muka air minimum 60 cm pada musim kemarau dan tinggi muka air maksimum 10 cm pada musim hujan. Penelitian ini bertujuan untuk mengetahui pola operasi dan pemeliharaan yang optimum melalui pengaturan pintu dalam mencapai kuantitas dan kualitas air yang sesuai untuk pengembangan sistem tata air di lahan irigasi rawa. Metode penelitian dilakukan dengan simulasi hidraulika berdasarkan pasang surut muara Sungai Barito, debit, curah hujan, dan pH yang diperoleh dari sistem monitoring telemetri dengan bukaan setiap pintu air pada saluran primer serta saluran sekunder. Hasil penelitian menunjukkan bahwa optimasi operasi dan pemeliharaan dapat dilakukan dengan pengaturan pintu air primer dan sekunder yang dibuka pada elevasi muka air di atas + 0,5 m pada musim kemarau sebagai supply dan elevasi muka air + 1,1 m pada musim penghujan sebagai drainase. Pintu air primer dan sekunder ditutup pada elevasi muka air di bawah + 0,5 m untuk menjaga tinggi muka air dan kualitas air.Kata Kunci:           optimasi, rawa, Daerah Irigasi Rawa Dadahup, HEC-RAS, hidrolika","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":"194 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139205873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ANALISIS RESAPAN LIMPASAN AIR HUJAN DALAM RANGKA PENERAPAN ZERO DELTA Q DI POLITEKNIK PU","authors":"Wildan Herwindo, Ingerawi Sekaring Bumi","doi":"10.32679/jth.v14i2.743","DOIUrl":"https://doi.org/10.32679/jth.v14i2.743","url":null,"abstract":"ABSTRACT Implementation of zero delta Q located at Polytechnic of Public Works specifically at Student Apartment is conducted by infiltrating runoff into the ground. The objectives of this study are to analyze runoff volume based on rainfall-runoff analysis and the quantity of water that can be absorbed based on soil permeability. The methods used were 1-dimensional (1-D) and 2-dimensional (2-D) of geoelectric tests. Soil permeability tests was added to and calculate the capacity of the infiltration wells. The research analysis was done using primary data including the measurement result of topography, geo-electric, soil permeability, and water quality , as well as secondary data of rainfall data for 10 years from 2011-2020, DEMNAS, geological map, groundwater basin, aquifer productivity, and a tower development master plan. The results of 1-D and 2-D geoelectrical analysis showed that the soil conditions in the study area were saturated and it was difficult to absorb water into the soil, and the permeability test showed a low value of soil permeability. Based on the calculation of infiltration well capacity, 554 infiltration wells are required to absorb the runoff, but it is difficult to carry out due to the limitation of available land area.  Therefore, zero delta Q must be applied through other efforts, for instance by implementing reuse mechanism of runoff. Based on the analysis, the reuse of runoff can fulfill the water needs of 288 people. However, the reuse of runoff at the research location requires prior processing so it is suitable for water quality standards.Keywords:       zero delta Q, geoelectric test, infiltration, runoff, permeability ABSTRAKSalah satu upaya penerapan zero delta Q di Kampus Politeknik PU tepatnya rusun mahasiswa dilakukan dengan peresapan air limpasan hujan ke dalam tanah. Tujuan penelitian ini yaitu menganalisis volume limpasan berdasarkan analisis curah hujan-limpasan dan kuantitas air yang dapat diresapkan berdasarkan permeabilitas tanah. Metode yang digunakan adalah uji geolistrik 1 dimensi (1-D) dan 2 dimensi (2-D). Uji permeabilitas tanah diterapkan untuk menghitung kapasitas sumur resapan. Analisis penelitian dilakukan dengan data primer berupa hasil pengukuran topografi, geolistrik, permeabilitas tanah, dan kualitas air, serta data sekunder berupa data hujan yang diperoleh dari stasiun hujan BMKG Semarang, stasiun hujan Bandara Ahmad Yani, dan stasiun hujan Maritim Tanjung Mas selama 10 tahun dari tahun 2011-2020, data DEMNAS, peta geologi, data cekungan air tanah, data produktivitas akuifer, dan master plan pembangunan rusun. Hasil analisis dengan geolistrik 1-D dan 2-D menunjukkan kondisi tanah di lokasi penelitian jenuh air dan sulit untuk meresapkan air ke dalam tanah, di samping itu pengujian dengan permeabilitas menunjukkan nilai permeabilitas tanah rendah. Berdasarkan perhitungan kapasitas sumur resapan, diperlukan sebanyak 554 buah sumur resapan untuk meresapkan limpasan yang terjadi, kondisi ini s","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":" 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139197680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EVALUASI KINERJA MODEL HUJAN ALIRAN LUMPED DALAM PENENTUAN ALIRAN DASAR DI DAERAH ALIRAN SUNGAI CITARUM","authors":"Brigita Diaz Primadita, M. S. B. Kusuma, Waluyo Hatmoko","doi":"10.32679/jth.v14i2.735","DOIUrl":"https://doi.org/10.32679/jth.v14i2.735","url":null,"abstract":"ABSTRACT Studies related to baseflow modeling are still rarely carried out compared to flood modeling. The commonly used rainfall-runoff models oversimplify the baseflow process, which leads to poor low-flow simulations. Baseflow plays an important role in regulating the seasonal distribution of river flow, maintaining aquatic habitats, and transporting chemical nutrients in the river system. If the baseflow decreases in the Citarum Watershed, there will be consequential impacts on the Java-Bali electricity supply, rice field irrigation water, raw water, and industrial water in West Java and DKI Jakarta. This study evaluates six lumped-rainfall-runoff models that are popularly used in the Ministry of Public Works and Housing of Indonesia, namely Mock, NRECA, HBV96, NAM, Sacramento, and Empirical to simulate baseflow on the Nanjung Subwatershed and Cisokan Subwatershed. The baseflow simulations from each model are compared with the observational baseflow. The observational baseflow is obtained using the Recursive Digital Filter Lyne and Holick one filter methods. To quantify model comparison, a multi-criteria matrix is used consisting of the model convenience, baseflow parameters, and model performance. This study shows that the Mock Model gives the best results with a \"Satisfactory\" score for simulating baseflow in NSE and RMSE values, the Q50-Q80 differences, and the difference in flow heights compared to the other five models. In addition, the Mock Model is also relatively easy, accessible, and familiar to use.Keywords:      Baseflow, Rainfall-Runoff, Lumped, Citarum, Recursive Digital FilterABSTRAKKajian terkait pemodelan aliran dasar masih jarang dilakukan dibandingkan pemodelan banjir. Model hujan-aliran yang umumnya digunakan mengasumsikan perhitungan aliran dasar secara sederhana sehingga menghasilkan simulasi aliran rendah yang buruk. Padahal penentuan aliran dasar sangat diperlukan mengingat pentingnya fungsi aliran dasar dalam mengatur distribusi musiman aliran sungai, mempertahankan habitat air, dan mengangkut nutrisi-bahan kimia dalam sistem sungai. Apabila terjadi penurunan aliran dasar di Daerah Aliran Sungai (DAS) Citarum maka dampaknya akan signifikan pada pasokan listrik Jawa-Bali, air irigasi sawah, air baku, dan air industri di Jawa Barat dan DKI Jakarta. Penelitian ini mengevaluasi enam model hujan-aliran lumped yang populer digunakan di Kementerian PUPR, yaitu Mock, NRECA, HBV96, NAM, Sacramento, dan Empiris untuk menentukan besarnya aliran dasar pada Sub-DAS Nanjung dan Sub-DAS Cisokan. Hasil pemodelan kemudian dibandingkan dengan hasil pemisahan aliran dasar dari debit observasi yang diperoleh melalui Metode Recursive Digital Filter Lyne dan Holick satu filter. Untuk memudahkan perbandingan model, digunakan matriks multi-kriteria dengan parameter pembanding kemudahan pemodelan, ada tidaknya parameter aliran dasar, dan kinerja model. Penelitian menunjukkan Model Mock memberikan hasil paling baik dengan skor “Memuaskan” untuk","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":"152 4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139208649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ALTERNATIF PERENCANAAN INTI TUBUH BENDUNGAN SEMANTOK MENGGUNAKAN GEOMEMBRAN","authors":"Yudhi Lastiasih, Anang Setyo Aji Widodo, Noor Endah","doi":"10.32679/jth.v14i2.742","DOIUrl":"https://doi.org/10.32679/jth.v14i2.742","url":null,"abstract":"ABSTRACT The Semantok Dam,  located in Rejoso District, Nganjuk Regency, has a total length of 3,005 m and a height of 26 m with a zonal type of fill. The dam body uses 5 types of natural materials as its constituent parts, namely lempung as the core, sand as a fine filter,  gravel as a coarse filter, random soil as the dominant material,  riprap and rocktoe materials as surface layers. The core material of the dam is lempung which meets the requirements to overcome seepage problems in the dam body. However, the volume of lempung material required is very large with high compaction. Therefore, it is necessary to plan alternative uses of replacement materials in the form of impermeable geosynthetics to reduce the thickness of the dam core. In planning, stability and seepage requirements must still be met. To carry out an analysis of the combined use of geomembran HDPE 2 mm in various variations in the thickness of the core zone, the Geo-Studio auxiliary program was used, where the Seep/W program was used to determine seepage and phreatic lines in the dam body, while the Lereng/W program was used to check the stability of the dam body. From several dam core thicknesses analyzed, the use of 2 mm HDPE geomembran material combined with 2/3 of the thickness of the existing core zone provides results that meet the requirements for seepage and dam stability. To overcome seepage under the dam body, secant piles are installed under the dam. The effect of earthquake loads was also analyzed where the dam remained safe for OBE earthquake loads of 100 years and 145 years; at an MDE of 10,000, the dam will experience minimum damage which still meets the requirements of 50% of the safety height with a deformation or diversion value of 15.36 cm.Keywords:      Semantok Dam, weir core, geomembran, stability, seepage ABSTRAKBendungan Semantok yang terletak di Kecamatan Rejoso Kabupaten Nganjuk memiliki panjang total mercu bendungan  3.005 m dan tinggi tubuh bendung 26 m dengan jenis urukan tipe zonal. Tubuh bendungan menggunakan 5 jenis material alam sebagai penyusunnya yaitu lempung sebagai inti, pasir sebagai filter halus, kerikil sebagai filter kasar, random tanah sebagai material dominan,  serta material riprap dan rocktoe sebagai lapisan permukaan. Material inti bendungan adalah tanah lempung yang memenuhi syarat untuk mengatasi masalah rembesan di tubuh bendungan. Hanya saja, volume material lempung yang dibutuhkan sangat banyak dengan pemadatan yang tinggi.  Oleh sebab itu, perlu direncanakan alternatif pemakaian material pengganti berupa geosintetik yang kedap untuk mengurangi ketebalan inti bendungan. Dalam perencanaannya, persyaratan stabilitas dan rembesan harus tetap dipenuhi. Untuk melakukan analisis terhadap kombinasi penggunaan geomembran HDPE 2 mm pada berbagai variasi ketebalan zona inti, digunakan program bantu Geo-Studio dimana program Seep/W untuk mengetahui rembesan dan garis freatik dalam tubuh bendungan, sedang program Lereng/W untuk cek stabi","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":" 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139197580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MEKANISME LONGSOR AKIBAT INFILTRASI DARI GENANGAN AIR (STUDI KASUS LONGSOR DI LAHAT, SUMATERA SELATAN)","authors":"R. Hidayat, I. Wijaya, Moh. Dedi Munir","doi":"10.32679/jth.v14i1.701","DOIUrl":"https://doi.org/10.32679/jth.v14i1.701","url":null,"abstract":"ABSTRACTThe landslide occurred in the Lahat-Pagaralam road section on February 2, 2019. The landslide caused the road to be cut off for several days. The disconnection of roads triggered disruption of economic activity. The landslide might be caused by a puddle of rainwater seeping into the road. Several cases of landslide triggered by ponding water also occurred on the Kuningan-Tasikmalaya road in Cikijing Tasikmalaya, and on the Gempol-Pandaan toll road in East Java.  The purpose of this study, therefore, was to determine the safety criteria based on the results of safety factors, the amount of seepage, and the pattern of collapse of the road, thus the incidents can be anticipated and are expected not to occur in other locations. The research method begins with field survey, depicting the geometry of the road, and collecting geotechnical data for landslide locations. Slope stability modeling due to water infiltration was processed using the SLOPE-W program. The results of road slope stability modeling at the landslide location show that when there is a 1m inundation, the slope stability value of factor of safety (FS) is 0.916 (a condition prone to landslides). The direction of flow comes from right to left, the right is a small slope and the left slope is a river bank. The difference in water level on the right and left of the road causes water to seep into the soil layer and cause the groundwater level to rise. The occurrence of water flow along the soil pile, causing water to fill the gaps between soil. The value of the slope stability number decreases due to water infiltration into the soil, resulting in landslides. SF value decreases from 0.916 to 0.887 when the inundation height increases from 1 m to 5 m. We concluded that the presence of water ponding around the road strongly suspected to be the cause of landslides. It is necessary to prevent ponding with a drainage system, so that it will not affect to the stability of the road.Keywords: landslide, slope stability, water infiltration, water ponding, drainage. ABSTRAKTelah terjadi longsor pada ruas jalan Lahat-Pagaralam pada 2 Februari 2019. Longsoran menyebabkan jalan terputus selama beberapa hari. Terputusnya ruas jalan menyebabkan gangguan aktivitas ekonomi. Longsor diduga disebabkan adanya genangan air hujan yang meresap ke badan jalan. Beberapa kasus longsor yang dipicu oleh genangan air juga terjadi pada ruas jalan Kuningan-Tasikmalaya di Cikijing Tasikmalaya, dan pada ruas tol Gempol-Pandaan Jawa Timur. Tujuan dari penelitian ini adalah untuk mengetahui kriteria keamanan lereng berdasarkan hasil analisis yang berupa angka faktor keamanan dan jumlah debit rembesan serta pola runtuh/longsor pada badan jalan, sehingga kejadian seperti ini bisa diantisipasi dan diharapkan tidak terjadi di lokasi lain. Metode penelitian diawali dengan survei lapangan, penggambaran geometri badan jalan, dan pengumpulan data geotek tanah lokasi longsor. Pemodelan stabilitas lereng akibat infiltasi air dil","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129705195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IDENTIFIKASI PERUBAHAN GARIS PANTAI MENGGUNAKAN PERANGKAT COASTSAT, STUDI KASUS SEGMEN PANTAI NUSA DUA, BALI","authors":"I. Permatasari, Totok Suprijo, Budhy Soeksmantono","doi":"10.32679/jth.v14i1.719","DOIUrl":"https://doi.org/10.32679/jth.v14i1.719","url":null,"abstract":"ABSTRACTNusa Dua Beach, Bali, is morphologically dynamic because it is constantly changing due to erosion and accretion. In 2003, the efforts were made to develop groins, where this one of the solutions to overcome erosion. Analysis of shoreline changes needs to be carried out to see the effectiveness of groin development by looking at the shoreline before and after construction using Landsat imagery data for 26 years. This research method utilizes the Modified Normalized Difference Water Index (MNDWI) algorithm to separate water from land features, classify images into four classes: sand, water, foam, and land features using the Coastsat toolkit and calculate wave energy flux. Before the construction, The GA1-GA2 groins experienced successive erosion in 1996-2002. After construction of the coastal groins, it still shows a decline in the coastline both during the west monsoon, which is 63.68 m and the east monsoon which is 36.21 m. In the east monsoon, the wave energy flux is most significant, with a maximum value of 4.9 x 10³ N/s, and in the west monsoon 3.4 x 10³ N/s. The effect of the significant wave energy flux that occurs in the east monsoon causes more longshore sediment transport, and the coast experiences a maximum shoreline advance in the east monsoon of 65.24 m compared of the west monsoon shoreline, which is 58.28 m. The toolkit can identify with better accuracy by validating estimation and observation data with an RMSE value of 4.79 m, a bias of 2.62 m, and an R2 of 0.97.Keywords: Shoreline, Erosion, Landsat, Wave Energy Flux  ABSTRAKPantai Nusa Dua, Bali dapat dikatakan secara morfologi dinamis dikarenakan selalu mengalami perubahan akibat erosi dan akresi. Tahun 2003 telah dilakukan upaya pembangunan groin yang merupakan salah satu solusi untuk menanggulangi terjadinya erosi. Analisis perubahan garis pantai perlu dilakukan untuk melihat efektivitas dari pembangunan groin dengan melihat garis pantai sebelum dan sesudah pembangunan dengan memanfaatkan data citra Landsat selama 26 tahun. Metode penelitian ini memanfaatkan algoritma Modified Normalized Difference Water Index (MNDWI) untuk memisahkan air dari fitur daratan, mengklasifikasi citra menjadi empat kelas: pasir, air, buih dan fitur lahan dengan menggunakan toolkit Coastsat serta menghitung fluks energi gelombang. Sebelum pembangunan groin GA1-GA2, pantai mengalami erosi pada tahun 1996-2002. Setelah pembangunan groin pantai masih menunjukkan terjadi kemunduran garis pantai pada saat musim barat 63,68 m maupun musim timur 36,21 m. Pada musim timur fluks energi gelombang terbesar dengan nilai maksimum 4,9 x 10³ N/s dan pada musim barat fluks energi maksimum yaitu sebesar 3,4 x 10³ N/s  Efek dari besarnya fluks energi gelombang yang terjadi di musim timur menyebabkan angkutan sedimen sejajar pantai lebih besar dan pantai mengalami kemajuan garis pantai maksimum di musim timur 65,24 m dibandingkan dengan musim barat 58,28 m. Toolkit coastsat mampu mengindentifikasi garis pantai l","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123782688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DESAIN TANGGUL SEBAGAI SOLUSI BANJIR DENGAN MODEL HIDRODINAMIK NUFSAW2D PADA DESA MAEN, SULAWESI UTARA","authors":"Bobby Minola Ginting","doi":"10.32679/jth.v14i1.722","DOIUrl":"https://doi.org/10.32679/jth.v14i1.722","url":null,"abstract":"ABSTRACT The Maen Village, Minahasa Utara Regency, Province of North Sulawesi, is located adjacent to the sea and on the confluence of three rivers namely Maen Besar River, Maen Kecil (Atas) River, and Maen Kecil (Samping) River. Hence, the village area is prone to flooding, especially when heavy rainfall and high tide water occur. Therefore, this research was conducted to study levee design as the flood solution for such a village. In this work, the flood simulation was conducted using a hydrodynamic model NUFSAW2D to predict the inundation pattern for the existing condition. It was shown that the existing levee constructed for the Maen Besar River could anticipate the 2-year return period flood. However, the capacity of the Maen Kecil River was insufficient for the 2-year flood, and consequently, it caused flooding in the Maen Village. For the 25-year return period flood, all the rivers had insufficient capacity. To deal with this problem, levee design was proposed, for which the crest level of the existing levee of the Main Besar River must be increased and the new levee toward its upstream part must be constructed. Meanwhile, along the Maen Kecil River, new levee must be constructed. The simulation results using NUFSAW2D showed that with such a levee system, the Maen Village became safe from the 25-year flood. Additionally, it was required to add two retention ponds to collect the overland flow water from the Main Village, and later to flow it back to the Maen Besar and Maen Kecil Rivers. The result of this study is expected to be useful for the related stakeholders to solve the flood problem for the Main Village.   Keywords:       flood, Maen Village, NUFSAW2D, levee ABSTRAKDesa Maen, Kabupaten Minahasa Utara, Provinsi Sulawesi Utara, terletak berbatasan dengan laut serta berada di pertemuan antara tiga sungai yaitu Sungai Maen Besar, Sungai Maen Kecil (Atas) dan Sungai Maen Kecil (Samping). Hal ini menyebabkan kawasan tersebut rawan banjir, khususnya saat hujan deras disertai dengan kondisi air pasang. Oleh sebab itu, studi ini dilakukan dengan tujuan mengkaji desain tanggul sebagai solusi penanganan banjir untuk kawasan tersebut. Kajian dilakukan berdasarkan simulasi banjir menggunakan model hidrodinamik NUFSAW2D untuk mengetahui pola genangan banjir kondisi eksisting. Dari hasil simulasi diketahui bahwa tanggul eksisting yang telah dibangun untuk Sungai Maen Besar mampu mengatasi banjir dengan kala ulang 2 tahun. Namun, kapasitas Sungai Maen Kecil tidak mampu mengalirkan debit banjir 2 tahunan sehingga menyebabkan banjir pada kawasan Desa Maen. Untuk kala ulang 25 tahun, kapasitas ketiga sungai tidak cukup untuk mengalirkan debit banjir. Untuk mengatasi masalah ini, penerapan sistem tanggul diusulkan, dimana tanggul eksisting yang berada pada sisi Sungai Maen Besar harus ditinggikan dan selanjutnya dibutuhkan pembangunan tanggul baru ke arah hulu. Sementara, sepanjang Sungai Maen Kecil tanggul baru harus dibangun. Hasil simulasi model NUF","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125111797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ANALISIS DAERAH TERDAMPAK BANJIR BANDANG MENGGUNAKAN HEC-RAS 2 DIMENSI DI SUNGAI SAT, KABUPATEN PATI, JAWA TENGAH","authors":"Jati Iswardoyo, Hafizh Satria","doi":"10.32679/jth.v14i1.717","DOIUrl":"https://doi.org/10.32679/jth.v14i1.717","url":null,"abstract":" ABSTRACT On Thursday, July 14, 2022, a flash flood occurred in Pati Regency, Central Java, caused by heavy rainfall with an intensity of up to 147.5 mm/day on the slopes of Mount Muria. resulting several rivers in Pati Regency overflowed, causing damage to embankments and triggering a flash flood that devastated residential areas and agricultural land. In this study, a simulation was conducted to estimate the extent of the affected area by flash floods in the Sat River, Pati Regency, in the future. The study utilized HEC-RAS version 6.2, which is capable of accurately simulating non-Newtonian fluid behavior, thus enabling precise simulation of flash floods. The simulation results revealed that the flash flood in the Sat River, Pati Regency, had an impacted area of 655 hectares with an average water depth of 3.25 meters for a 2-year return period. For a 25-year return period, the impacted area increased to 1,017 hectares with an average water depth of 3.04 meters, while for a 50-year return period, the impacted area reached 1,091 hectares with an average water depth of 3.01 meters. This research provides a better understanding of the impact of flash floods in the Sat River, Pati Regency, and can serve as a reference for future disaster mitigation efforts. By knowing the extent of the affected area and the average water depth, more effective preventive and management measures can be implemented to mitigate the significant losses caused by flash floods.Keywords:       flash flood, flood mitigation, flood simulation, HEC-RAS, hydraulic analysis, Pati Regency  ABSTRAKPada Kamis, 14 Juli 2022, banjir bandang terjadi di Kabupaten Pati, Provinsi Jawa Tengah yang disebabkan oleh curah hujan dengan intensitas mencapai 147,5 mm/hari di lereng Gunung Muria. Akibatnya, sejumlah sungai di Kabupaten Pati meluap, menyebabkan kerusakan pada tanggul dan memicu banjir bandang yang merusak permukiman penduduk serta lahan persawahan. Dalam penelitian ini, dilakukan simulasi dengan tujuan untuk memperkirakan luas area yang terdampak banjir bandang di Sungai Sat, Kabupaten Pati, di masa depan. Studi ini menggunakan perangkat lunak HEC-RAS versi 6.2 yang memiliki kemampuan untuk melakukan simulasi fluida dengan sifat non-Newtonian, sehingga simulasi banjir bandang dapat dilakukan secara akurat. Hasil dari simulasi menunjukkan bahwa banjir bandang di Sungai Sat, Kabupaten Pati, memiliki luas terdampak sebesar 655 hektar dengan kedalaman air rata-rata mencapai 3,25 meter untuk periode ulang 2 tahunan. Pada periode ulang 25 tahunan, luas dampak meningkat menjadi 1.017 hektar dengan kedalaman air rata-rata sebesar 3,04 meter, sedangkan untuk periode ulang 50 tahunan, luas dampak mencapai 1.091 hektar dengan kedalaman air rata-rata sebesar 3,01 meter. Penelitian ini memberikan pemahaman yang lebih baik mengenai dampak banjir bandang di Sungai Sat, Kabupaten Pati, dan dapat digunakan sebagai acuan dalam upaya mitigasi bencana di masa depan. Dengan mengetahui luas area yang t","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":"2 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123545485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PEMODELAN SEDIMENTASI MENGGUNAKAN HEC-RAS 6.1 UNTUK MENGANALISIS PERUBAHAN ELEVASI DASAR SUNGAI TONDANO, SULAWESI UTARA","authors":"Muhammad Taufiq Makmur Zainuddin, Irmanto Irmanto, Joko Nugroho, Waluyo Hatmoko","doi":"10.32679/jth.v14i1.721","DOIUrl":"https://doi.org/10.32679/jth.v14i1.721","url":null,"abstract":"ABSTRACT Sedimentation is a problem that can cause siltation and changes in river morphology due to reduced river capacity and increased runoff. The Tondano River is one of the major rivers that cross the City of Manado, which has a significant contribution in terms of the impact of flooding and, in its current conditions, has experienced considerable siltation so that the capacity of the river is unable to carry discharge. This study aims to analyze the changes in the elevation of the Tondano River bed that occurred within 6 years from 2016 to 2022 due to sedimentation. Sedimentation modelling is done using the HEC-RAS 6.1 application because, it has new features and improvements over the previous version, especially for, sediment transport analysis using the Meyer Peter Muller empirical equation. The bathymetric data used is the 2016 measurement, and a sediment model simulation is carried out for a 6-year daily discharge period. Then verification is carried out with the 2022 bathymetry data and current field conditions. The results show that the Tondano River on the Kairagi section, along 7.20 km from the estuary, experienced a significant change in riverbed elevation due to sedimentation. There was an average aggradation or sedimentation thickness of 0.891 m for 6 years and an estimated 0.130 to 0.140 m per year, so under these conditions, the cross-section of the Tondano River experienced siltation and reduced the capacity of the river to carry flood discharge. The simulation results showed that changes in river bed elevation also cause an increase in water level as high as 1 to. 2 m. From the simulation results of changes in the bottom of the Tondano River section of Kairagi, a total sedimentation amount of 83,087.49 m3 for 6 years was obtained.Keywords: sedimentation, river bed elevation, water surface elevation, aggradation, deposition ABSTRAKSedimentasi merupakan permasalahan yang dapat menyebabkan terjadinya pendangkalan dan perubahan morfologi sungai karena berkurangnya kapasitas sungai sehingga terjadi peningkatan aliran permukaan. Sungai Tondano adalah salah satu sungai besar yang melintas di Kota Manado yang menjadi salah satu sungai yang memiliki kontribusi besar dalam hal dampak banjir dan pada kondisi saat ini telah mengalami pendangkalan yang signifikan sehingga kapasitas sungai tidak mampu dalam mengalirkan debit. Tujuan penelitian ini yaitu untuk menganalisis perubahan elevasi dasar Sungai Tondano yang terjadi dalam kurun waktu 6 tahun dari tahun 2016 hingga 2022 akibat sedimentasi. Pemodelan sedimentasi dilakukan menggunakan aplikasi HEC-RAS 6.1 karena pada versi ini terdapat beberapa fitur baru dan perbaikan dari versi sebelumnya, yaitu persamaan angkutan sedimen menggunakan persamaan empiris Meyer Peter Muller. Data batimetri yang digunakan adalah pengukuran tahun 2016 dan dilakukan simulasi model sedimen selama periode debit harian 6 tahun kemudian dilakukan verifikasi dengan data batimetri tahun 2022 serta kondisi lapangan","PeriodicalId":356205,"journal":{"name":"JURNAL TEKNIK HIDRAULIK","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128752696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}