5 research outputs found
Prediksi Morfologi Dasar Sungai Akibat Variasi Tutupan Vegetasi Tebing Sungai Way Sekampung
Perubahan tata guna lahan sangat berdampak pada degradasi fungsi hutan karena hutan merupakan salah satu komponen ekosistem yang berfungsi sebagai penyanggga kawasan di bawahnya yang dapat mempengaruhi Perubahan debit banjir dan erosi lahan dalam kawasan DAS. Alih fungsi kawasan hutan menjadi pertanian, pemukiman maupun industri dapat mengakibatkan Perubahan terhadap puncak debit dan tingginya tingkat erosi yang terjadi pada lahan.Vegetasi mempunyai peranan yang sangat besar dalam penekanan erosi tanah. Pada hutan rimba, hampir tidak terjadi erosi tanah dan kalaupun ada kehilangan tanah tidak jauh berbeda dengan kecepatan pembentukan tanah. Sebaliknya tanah yang tanpa vegetasi hampir selalu terjadi erosi dan kehilangan tanah jauh lebih besar daripada tanah yang terbentuk. Beberapa upaya penanggulangan erosi tebing sungai Way Sekampung dengan menggunakan struktur telah dilaksanakan yaitu dengan pemasangan bronjong dan pasangan batu kali, tetapi penelitian terhadap efektivitas penanggulangan banjir yang dilaksanakan belum ada. Dalam penelitian ini dilakukan perhitungan debit banjir rancangan, yaitu untuk kala ulang Q2, Q5, Q10, Q25, Q50, dan Q100 tahun, inventarisasi vegetasi tebing sungai, uji laboratorium data sedimen, pengukuran debit sesaat dengan menggunakan current meter dan uji pena erosi untuk mengetahui erosi tebing yang terjadi. Data-data tersebut kemudian disimulasikan bersama dengan data penampang sungai (long & cross) ke dalam sofware HEC RAS versi 4.0. Dalam penelitian ini dibagi dalam tiga skenario yaitu skenario 1 dengan tutupan vegetasi (0-30%), skenario 2 tutupan vegetasi (30-60% dan skenario 3 dengan tutupan vegetasi > 60%. Sedangkan untuk memudahkan dalam analisis hasil running HEC RAS 4.0 maka daerah penelitian dibagi menjadi tiga segmen yaitu segmen A yang mengalami erosi (degradasi), segmen B yang mengalami sedimentasi (agradasi) dan segmen C yang tidak mengalami Perubahan elevasi dasar sungai. Pada masing-masing segmen di ambil 4 titik uji analisis yang mewakilinya. Berdasarkan hasil Running HEC RAS 4.0 pada skenario 1 tutupan vegetasi (0-30%) terlihat adanya Perubahan dasar sungai jika dibandingkan dengan kondisi eksisting, sedangkan skenario 2 tutupan vegetasi (30-60%) hasilnya hampir sama dengan eksisting hanya pada titik tertentu terjadi variasi, sedangkan pada skenario 3 tutupan vegetasi (> 60%) Perubahan elevasi dasar sungai lebih variatif jika dibandingkan dengan kondisi eksisting. Makin besar prosentase tutupan vegetasi tebing sungai maka Perubahan morfologi dasar sungai akan semakin kecil. Hal ini disebabkan karena erosi yang terjadi pada tebing sungai lebih kecil. Perubahan tinggi elevasi dasar sungai (relatif) Way Sekampung berdasarkan hasil Running HEC RAS 4.0 pada masing-masing segmen dengan 4 titik uji setelah dirata-ratakan adalah untuk segmen A sebesar 0.36 m, segmen B sebesar 1.44 m dan segmen C sebesar 0.26 m.Land use change has an impact to degradation of forest function because the forest is one of ecosystem components as the buffer of the region below that could influence the flood discharge change and land erosion in the river DAS area. The switch of forest area function into farming, housing even industry could result in change of discharge peak and the erosion level height that could occure to the land. Vegetation has very big part in land erosion compression. In the jungle, almost there is no land erosion and if there is, the lost of the land is not so different between the velocity of land forming. On the contrary, theres almost always happen the land erosion in the land without vegetation and the lost of the land is bigger than the formed land. Some efforts in dealing with slope erosion of Way Sekampung are using the structur that have been done which are the concertina and stone installation, but the effectivity has not been researched. In this research, it has calculated of flood discharge design based on year period for Q2, Q5, Q10, Q50 and Q100 year, the river slope inventory, sediment laboratory test, measurement of in time discharge using current meter and pen erosion test to find out the slope erosion that occured. Those data will be simulated together with long & cross river section using HEC RAS version 4.0 software. This research divided by three scenarios, scenario 1 : vegetation cover 0-30%, scenario 2 : vegetation cover 30-60% and scenario 3 : vegetation cover > 60%. In order to ease the analysis of HEC RAS running result, so that the research area divided by three segments, which are segment A : has experienced erosion (degradation), segment B : has experienced sedimentation (agredation) and segment C : has no experience in river bed elevation change. Each segment was taken 4 test points that represent the experience. Based on the running result by HEC RAS 4.0 on scenario 1 : vegetation cover 0-30% showed the change of river bed compare to the existing condition, while the scenario 2 ; vegetation cover 30-60% showed the similar with the existing condition, only in certaint points variation occured. The scenario 3 : vegetation cover .>60% showed the change of river bed elevation was more vary than the existing condition. The greater the precentage of vegetation cover of river slope the the less change of river bed morphology. That is caused by the erosion at the river slope is less. The average of change of way sekampung river bed elevation based on running result HEC RAS 4.0 for each segment with 4 test points are segment A laid on 0.36 m, segment B laid on 1.44 m and segment C laid on 0.26 m
Prediksi Morfologi Dasar Sungai Akibat Variasi Tutupan Vegetasi Tebing Sungai Way Sekampung
Perubahan tata guna lahan sangat berdampak pada degradasi fungsi hutan karena hutan merupakan salah satu komponen ekosistem yang berfungsi sebagai penyanggga kawasan di bawahnya yang dapat mempengaruhi perubahan debit banjir dan erosi lahan dalam kawasan DAS. Alih fungsi kawasan hutan menjadi pertanian, pemukiman maupun industri dapat mengakibatkan perubahan terhadap puncak debit dan tingginya tingkat erosi yang terjadi pada lahan.Vegetasi mempunyai peranan yang sangat besar dalam penekanan erosi tanah. Pada hutan rimba, hampir tidak terjadi erosi tanah dan kalaupun ada kehilangan tanah tidak jauh berbeda dengan kecepatan pembentukan tanah. Sebaliknya tanah yang tanpa vegetasi hampir selalu terjadi erosi dan kehilangan tanah jauh lebih besar daripada tanah yang terbentuk. Beberapa upaya penanggulangan erosi tebing sungai Way Sekampung dengan menggunakan struktur telah dilaksanakan yaitu dengan pemasangan bronjong dan pasangan batu kali, tetapi penelitian terhadap efektivitas penanggulangan banjir yang dilaksanakan belum ada. Dalam penelitian ini dilakukan perhitungan debit banjir rancangan, yaitu untuk kala ulang Q2, Q5, Q10, Q25, Q50, dan Q100 tahun, inventarisasi vegetasi tebing sungai, uji laboratorium data sedimen, pengukuran debit sesaat dengan menggunakan current meter dan uji pena erosi untuk mengetahui erosi tebing yang terjadi. Data-data tersebut kemudian disimulasikan bersama dengan data penampang sungai (long & cross) ke dalam sofware HEC RAS versi 4.0. Dalam penelitian ini dibagi dalam tiga skenario yaitu skenario 1 dengan tutupan vegetasi (0-30%), skenario 2 tutupan vegetasi (30-60% dan skenario 3 dengan tutupan vegetasi > 60%. Sedangkan untuk memudahkan dalam analisis hasil running HEC RAS 4.0 maka daerah penelitian dibagi menjadi tiga segmen yaitu segmen A yang mengalami erosi (degradasi), segmen B yang mengalami sedimentasi (agradasi) dan segmen C yang tidak mengalami perubahan elevasi dasar sungai. Pada masing-masing segmen di ambil 4 titik uji analisis yang mewakilinya. Berdasarkan hasil Running HEC RAS 4.0 pada skenario 1 tutupan vegetasi (0-30%) terlihat adanya perubahan dasar sungai jika dibandingkan dengan kondisi eksisting, sedangkan skenario 2 tutupan vegetasi (30-60%) hasilnya hampir sama dengan eksisting hanya pada titik tertentu terjadi variasi, sedangkan pada skenario 3 tutupan vegetasi (> 60%) perubahan elevasi dasar sungai lebih variatif jika dibandingkan dengan kondisi eksisting. Makin besar prosentase tutupan vegetasi tebing sungai maka perubahan morfologi dasar sungai akan semakin kecil. Hal ini disebabkan karena erosi yang terjadi pada tebing sungai lebih kecil. Perubahan tinggi elevasi dasar sungai (relatif) Way Sekampung berdasarkan hasil Running HEC RAS 4.0 pada masing-masing segmen dengan 4 titik uji setelah dirata-ratakan adalah untuk segmen A sebesar 0.36 m, segmen B sebesar 1.44 m dan segmen C sebesar 0.26 m.Land use change has an impact to degradation of forest function because the forest is one of ecosystem components as the buffer of the region below that could influence the flood discharge change and land erosion in the river DAS area. The switch of forest area function into farming, housing even industry could result in change of discharge peak and the erosion level height that could occure to the land. Vegetation has very big part in land erosion compression. In the jungle, almost there is no land erosion and if there is, the lost of the land is not so different between the velocity of land forming. On the contrary, theres almost always happen the land erosion in the land without vegetation and the lost of the land is bigger than the formed land. Some efforts in dealing with slope erosion of Way Sekampung are using the structur that have been done which are the concertina and stone installation, but the effectivity has not been researched. In this research, it has calculated of flood discharge design based on year period for Q2, Q5, Q10, Q50 and Q100 year, the river slope inventory, sediment laboratory test, measurement of in time discharge using current meter and pen erosion test to find out the slope erosion that occured. Those data will be simulated together with long & cross river section using HEC RAS version 4.0 software. This research divided by three scenarios, scenario 1 : vegetation cover 0-30%, scenario 2 : vegetation cover 30-60% and scenario 3 : vegetation cover > 60%. In order to ease the analysis of HEC RAS running result, so that the research area divided by three segments, which are segment A : has experienced erosion (degradation), segment B : has experienced sedimentation (agredation) and segment C : has no experience in river bed elevation change. Each segment was taken 4 test points that represent the experience. Based on the running result by HEC RAS 4.0 on scenario 1 : vegetation cover 0-30% showed the change of river bed compare to the existing condition, while the scenario 2 ; vegetation cover 30-60% showed the similar with the existing condition, only in certaint points variation occured. The scenario 3 : vegetation cover .>60% showed the change of river bed elevation was more vary than the existing condition. The greater the precentage of vegetation cover of river slope the the less change of river bed morphology. That is caused by the erosion at the river slope is less. The average of change of way sekampung river bed elevation based on running result HEC RAS 4.0 for each segment with 4 test points are segment A laid on 0.36 m, segment B laid on 1.44 m and segment C laid on 0.26 m
PEMANENAN AIR HUJAN SEBAGAI PENYEDIAAN AIR BERSIH PADA ERA NEW NORMAL DI KELURAHAN SUSUNAN BARU
ABSTRAKSusunan Baru merupakan kelurahan yang berada di kecamatan Tanjung Karang Barat, Kota Bandar Lampung, Lampung. Kelurahan Susunan Baru tidak jarang mendapatkan bantuan air bersih berupa penyaluran air bersih. Hal ini dilakukan dalam rangka merespon sulitnya akses air bersih diwilayah tersebut dikarenakan kondisi tanah berbatu dan berada didataran tinggi. Sudah sejak Kelurahan Susunan Baru kesulitan dalam mendapatkan air bersih apabila musim kering tiba. Kegiatan Pengabdian Kepada Masyarakat diharapkan dapat memberikan pengetahuan mengenai cara mendapatkan alternatif sumber air bersih dari air hujan dan meningkatkan pemahaman pentingnya memanfaatkan air hujan sebagai sumber air bersih untuk kebutuhan mandi dan mencuci serta diharapkan dapat memberikan keterampilan baru bagi masyarakat dalam membuat teknologi pemanenan air hujan yang dapat menjadi sumber air bersih untuk pemenuhan kebutuhan air bersih di tingkat rumah tangga. Alat panen hujan yang telah dibuat berfungsi dengan baik karena pada saat hujan turun air hujan masuk kedalam alat panen hujan dan ditampung. Dengan perhitungan volume air hujan dengan berbagai asumsi didapatkan air yang dapat ditampung selama seminggu adalah sebanyak 1350 liter. Jika dalam satu hari air yang digunakan untuk mencuci tangan mencapai 60 Liter. Maka air yang tertampung mampu memenuhi kebutuhan mencuci tangan selama 22 hari. Dari hasil Pengabdian yang dilakukan diketahui bahwa Kelurahan dapat menghemat penggunaan air untuk cuci tangan selama 22 hari dengan terisinya alat panen hujan, terlebih lagi jika hujan yang terjadi lebih dari 3 kali seminggu. Adanya tampungan dari air hujan menambah sumber air baru yang dapat dimanfaatkan untuk kegiatan sehari-hari dan menjadi suatu alternatif dalam penyediaan air bersih Kata kunci: air hujan; pemanenan air hujan; sumber air bersih. ABSTRACTSusunan Baru is a village located in Tanjung Karang Barat sub-district, Bandar Lampung City, Lampung. Kelurahan Susunan Baru often receives clean water assistance in the form of clean water distribution. This is done in response to the difficulty of access to clean water in the area due to the rocky soil conditions and highlands. Already, Susunan Baru Village has had difficulty getting clean water when the dry season arrives. Community Service Activities are expected to provide knowledge about how to obtain alternative sources of clean water from rainwater and increase understanding of the importance of utilizing rain water as a source of clean water for bathing and washing needs and are expected to provide new skills for the community in making rainwater harvesting technology that can become a source of clean water to meet the needs of clean water at the household level. The rain harvesting tool that has been made functions well because when it rains, the rainwater enters the rain harvesting tool and is collected. By calculating the volume of rainwater with various assumptions, it is found that the water that can be stored for a week is as much as 1350 liters. If in one day the water used to wash hands reaches 60 liters. Then the collected water is able to meet the needs of washing hands for 22 days. From the results of the Community Service, it is known that the Kelurahan can save water use for washing hands for 22 days by filling up rain harvesting tools, especially if it rains more than 3 times a week. The existence of storage from rainwater adds new water sources that can be used for daily activities and becomes an alternative in the provision of clean water Keywords: rain water; rain water harvesting;source of clean water
Analysis of urban flood using synthetic unit hydrograph (SUH) and flood mitigation strategies along way Halim River: a case study on Seroja street, Tanjung Senang District
In the urban area, flooding becomes the most common disaster that has not been resolved until today. The utilization of river border area into housing and lack of absorption area becomes the trigger factor of urban flooding, as what is happening around Way Halim River on Seroja street. In this area, floods often happen during the rainy season, with the latest events recorded on January 21st, 2021. Analysis of flood intensities and discharges can be parameters for the decision-making of flood mitigation strategies. This study aims to analyze the flood discharges along Way Halim River, Seroja street by comparing the flood discharges resulting from three analysis methods of Synthetic Unit Hydrograph (SUH) including Gama I SUH, Nakayasu SUH, and Snyder SUH. Finally, suitable flood mitigation strategies were also proposed in this study based on the flood discharges and rain intensities. The results showed that Nakayasu SUH had the highest peak flood discharge than Snyder SUH and Gama I SUH. Based on the results of the investigation of land suitability; and analysis of rainfall intensities and flood discharges, the proposed flood mitigation in Seroja street is by installing biopore infiltration holes along Seroja street for storing water and reducing the risk of flooding in the area
Performance of small reservoirs in Tulang Bawang Watershed for microhydro power plant
Recurring floods in the Tulang Bawang River have led to significant losses. In response, the government and local engineers have taken steps to manage flood events and harness excess water for electrical energy generation through the construction of five small reservoirs in the Tulang Bawang watershed. This study evaluates the performance of these reservoirs as micro-hydro power plants, with the aim of mitigating energy challenges in Lampung Province. To achieve this goal, we collected and analyzed hydrological data and calculated the potential electrical power output for each reservoir. By utilizing a 50- meter waterfall height, the sub-watersheds of Way Giham, Way Umpu, and Way Tahmi, with a combined water holding capacity of approximately 2 million cubic meters, are capable of generating around 3 MW of electrical power per reservoir. Similarly, Way Tuba and Way Basei sub-watersheds offer a potential of approximately 4 MW of electrical power per reservoir. Based on these calculations, it is evident that the small reservoirs in the Tulang Bawang watershed hold substantial potential for contributing to the electrical power supply, thereby addressing Lampung Province's energy challenges. These findings underscore the significance of utilizing available water resources to meet energy demands and promote sustainable development in flood-prone areas