Analysis Study Effect Of Surabaya's Northern Sea Tides On The Highway Drainage Channels  (Case Study: Kedung Mangu Road, Sidotopo Wetan, Kenjeran, Surabaya)

One of the roads that is still a subscription to flooding in Surabaya when it rains is on Kedung Mangu road. Besides being close to the northern coast of Surabaya, Kedung Mangu road channel edge is still very small and a lot of trash and sediment. In this study the authors used secondary Gumbel method using the data from relevant agencies and secondary of data from observations in the field. Reviews These rainfall of data include the data, the data pool of the data the tide and the dimensions of the existing channels and other auxiliary buildings. From the data and the calculation, the value of the average rainfall is 93.41 mm / day. Rainfall intensity 25-year period is 47.949 mm / hour. While the flood discharge plan is 174.859 m3 / h. Its existing discharge chute is 100 908 m3 / h. From the Data Obtained tide high tide value of 150 cm occurred on December 13, 2016 and to its Lowest ebb -130 cm occurred on January 25, 2016. Thet Type of Surabaya's northern sea tides is the mixed tide. From the calculation and analysis can be concluded that the more influential is the amount of rainfall and dimensions and road conditions in the channel Kedung Mangu. So as to cope with floods In These locations, the dimensions of the channel should be enlarged.

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Study of Flood and Coastal Flood Control in Madukoro Area, Semarang City, Indonesia

Journal of the Civil Engineering Forum ◽

10.22146/jcef.38126 ◽

2018 ◽

Vol 4 (3) ◽

pp. 189

Author(s):

Dian Wahyu Jatmiko

Keyword(s):

Water Level ◽

Land Subsidence ◽

Return Period ◽

Flood Control ◽

High Tide ◽

Northern Coast ◽

Flood Peak ◽

Runoff Volume ◽

Total Runoff ◽

Drainage Channels

Madukoro area located on the northern coast of Semarang City has been prone to flooding caused by rainfall and seawater high-tide. Ineffective flood control management and land subsidence are considered as the cause of this problem. In order to understand land subsidence effect and flood control performance, location, water surface height of the inundation in West Flood Canal, western part of Madukoro area need to analyze. Flood analysis was conducted using HEC-HMS software and rational method. Flow hydraulics on five channels, i.e. the West Flood Canal, Ronggolawe River, Karangayu River, Arterial Channel and Madukoro were analyzed using HEC-RAS software. Increasing levee level and additional water pumps in Madukoro and Ronggolawe were chosen as flood control alternatives. Its performance was investigated through software simulation. The results showed total runoff volume in all drainage channels for 2-years return period discharge was about 80% of capacity with 0.7 m water depth. Runoff volume in West Flood Canal with 50-years return period discharge was about 40%. Land subsidence 4 cm/year affected the water level increase on West Flood Canal. Operation of 2 - 4 pump units could not significantly decrease water level at flood peak, yet increase flood recession time 6 - 8 hours.

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Design of experimental food patches to measure foraging intensity for octopus: a case study with the giant Pacific octopus Enteroctopus dofleini

Journal of Molluscan Studies ◽

10.1093/mollus/eyaa039 ◽

2020 ◽

Author(s):

Stephanie Chancellor ◽

David Scheel ◽

Joel S Brown

Keyword(s):

Predation Risk ◽

Foraging Behaviour ◽

Habitat Preferences ◽

High Tide ◽

Intertidal Habitat ◽

Camera System ◽

Subtidal Habitat ◽

Enteroctopus Dofleini ◽

Nontarget Species

ABSTRACT In a study of the foraging behaviour of the giant Pacific octopus Enteroctopus dofleini, we designed two types of experimental food patches to measure habitat preferences and perceptions of predation risk. The first patch successfully measured giving-up densities (GUDs), confirmed by octopus prey presence and higher foraging at sites with historically greater octopus presence. However, nontarget foragers also foraged on these experimental food patches. Our second floating patch design successfully excluded nontarget species from subtidal patches, and from intertidal patches at high tide, but allowed for foraging by E. dofleini. The second design successfully measured GUDs and suggested that octopus preferred foraging in a subtidal habitat compared to an intertidal habitat. We ascribe the higher GUD in the intertidal habitat to its higher predation risk relative to the subtidal habitat. The second patch design seems well suited for E. dofleini and, in conjunction with a camera system, could be used to provide behavioural indicators of the octopus's abundance, perceptions of habitat quality and predation risk.

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Mangrove Forest Landcover Changes in Coastal Vietnam: A Case Study from 1973 to 2020 in Thanh Hoa and Nghe An Provinces

Forests ◽

10.3390/f12050637 ◽

2021 ◽

Vol 12 (5) ◽

pp. 637

Author(s):

Huong Thi Thuy Nguyen ◽

Giles E. S. Hardy ◽

Tuat Van Le ◽

Huy Quoc Nguyen ◽

Hoang Huy Nguyen ◽

...

Keyword(s):

Mangrove Forest ◽

Monsoon Season ◽

Coastal Development ◽

Northern Coast ◽

Mangrove Forests ◽

Visual Interpretation ◽

Mangrove Restoration ◽

Coast Of Vietnam ◽

Landsat Satellite

Mangrove forests can ameliorate the impacts of typhoons and storms, but their extent is threatened by coastal development. The northern coast of Vietnam is especially vulnerable as typhoons frequently hit it during the monsoon season. However, temporal change information in mangrove cover distribution in this region is incomplete. Therefore, this study was undertaken to detect change in the spatial distribution of mangroves in Thanh Hoa and Nghe An provinces and identify reasons for the cover change. Landsat satellite images from 1973 to 2020 were analyzed using the NDVI method combined with visual interpretation to detect mangrove area change. Six LULC classes were categorized: mangrove forest, other forests, aquaculture, other land use, mudflat, and water. The mangrove cover in Nghe An province was estimated to be 66.5 ha in 1973 and increased to 323.0 ha in 2020. Mangrove cover in Thanh Hoa province was 366.1 ha in 1973, decreased to 61.7 ha in 1995, and rose to 791.1 ha in 2020. Aquaculture was the main reason for the loss of mangroves in both provinces. Overall, the percentage of mangrove loss from aquaculture was 42.5% for Nghe An province and 60.1% for Thanh Hoa province. Mangrove restoration efforts have contributed significantly to mangrove cover, with more than 1300 ha being planted by 2020. This study reveals that improving mangrove restoration success remains a challenge for these provinces, and further refinement of engineering techniques is needed to improve restoration outcomes.

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Behavior of Offshore Pile in Calcareous Sand—Case Study

Journal of Marine Science and Engineering ◽

10.3390/jmse9080839 ◽

2021 ◽

Vol 9 (8) ◽

pp. 839

Author(s):

Tarek N. Salem ◽

Nadia M. Elkhawas ◽

Ahmed M. Elnady

Keyword(s):

Load Capacity ◽

High Stress ◽

Embedment Depth ◽

Shear Stresses ◽

Northern Coast ◽

Compression Tests ◽

Calcareous Sand ◽

Element Analysis ◽

Mixing Ratios

The erosion of limestone and calcarenite ridges that existed parallel to the Mediterranean shoreline forms the calcareous sand (CS) formation at the surface layer of Egypt's northern coast. The CS is often combined with broken shells which are considered geotechnically problematic due to their possible crushability and relatively high compressibility. In this research, CS samples collected from a site along the northern coast of Egypt are studied to better understand its behavior under normal and shear stresses. Reconstituted CS specimens with different ratios of broken shells (BS) are also investigated to study the effect of BS ratios on the soil mixture strength behavior. The strength is evaluated using laboratory direct-shear and one-dimensional compression tests (oedometer test). The CS specimens are not exposed to significant crushability even under relatively high-stress levels. In addition, a 3D finite element analysis (FEA) is presented in this paper to study the degradation offshore pile capacity in CS having different percentages of BS. The stress–strain results using oedometer tests are compared with a numerical model, and it gave identical matching for most cases. The effects of pile diameter and embedment depth parameters are then studied for the case study on the northern coast. Three different mixing ratios of CS and BS have been used, CS + 10% BS, CS + 30% BS, and CS + 50% BS, which resulted in a decrease of the ultimate vertical compression pile load capacity by 8.8%, 15%, and 16%, respectively.

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Evaluation of Drainage Channels Capacity in Ambon City: A Case Study on Wai Batu Merah Watershed Flooding

Procedia Engineering ◽

10.1016/j.proeng.2015.11.038 ◽

2015 ◽

Vol 125 ◽

pp. 263-269 ◽

Cited By ~ 1

Author(s):

Cilcia Kusumastuti ◽

Ruslan Djajadi ◽

Angel Rumihin

Keyword(s):

Drainage Channels

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Development of Rainfall Intensity-Duration-Frequency Curves Based on Dynamically Downscaled Climate Data: Arizona Case Study

Journal of Hydrologic Engineering ◽

10.1061/(asce)he.1943-5584.0002068 ◽

2021 ◽

Vol 26 (5) ◽

pp. 05021005

Author(s):

Amin Mohebbi ◽

Simin Akbariyeh ◽

Montasir Maruf ◽

Ziyan Wu ◽

Juan Carlos Acuna ◽

...

Keyword(s):

Rainfall Intensity ◽

Climate Data ◽

Intensity Duration Frequency ◽

Frequency Curves

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Pengaruh Curah Hujan dan Debit Air Terhadap Produktivitas Energi Listrik yang Dihasilkan Pada Pembangkit Listrik Tenaga Air (Studi Kasus: Sub Unit PLTA Kracak, Kabupaten Bogor Jawa Barat)

Journal of Electrical Vocational Education and Technology ◽

10.21009/jevet.0051.09 ◽

2020 ◽

Vol 5 (1) ◽

pp. 56-60

Author(s):

Wildan Gunawan ◽

Suyitno Muslim ◽

Imam Arif Rahardjo

Keyword(s):

River Discharge ◽

Research Method ◽

Rainfall Intensity ◽

Discharge Rate ◽

Electrical Power ◽

Electric Energy ◽

Energy Productivity ◽

Rain Fall ◽

Average Rain

This research is aimed to understand the effects of rain fall and discharge rate towards hydro electric power plant productivity (case study at Kracak Sub Unit HPP, Bogor Regency Jawa Barat). Multiple regression tecnique analysis is used as research method with quantitative approach for describing the effects of rain fall and discharge rate towards hydro electric energy productivity. Based on Sub Unit PLTA Kracak during a highest down pour in June 2018 has gained electrical power about 173,583 kWh for 15,84 mm rain fall and the lowest rain fall in July 2018 is 0,86 mm only obtain 49,772 kWh electrical power with the average rain fall record in three stations is 8,9592 mm. Mean while, for the highest river discharge rate happened in February is 10,08 m3/detik which produce 198,296 kWh electrical power and the lowest in June that only gained 3,53 m3/detik which produce 49,772 kWh electrical power with the average of river discharge rate in 2018 is only 7,9858 m3/detik. The average of electrical power it self is only 156,0105 kWh for 8,9592 mm of rainfall and 7,9858 m3/detik river discharge rate record in 2018. The conclusion oh this research is the discharge rate in headwaters area is affected by rainfall intensity, but not necessarily affected to hydro electric energy productivity. ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui pengaruh curah hujan dan debit air terhadap produktivitas energi listrik yang dihasilkan pada pembangkit listrik tenaga air (Studi Kasus: Sub Unit PLTA Kracak, Kabupaten Bogor Jawa Barat). Metode yang digunakan dalam penelitian ini adalah metode deskriptif dengan pendekatan kuantitatif teknik analisis data regresi berganda untuk mendiskripsikan data penelitian curah hujan dan debit air terhadap produktivitas energi listrik yang dihasilkan. Berdasarkan data hasil penelitian yang diperoleh di Sub Unit PLTA Kracak data curah hujan tertinggi pada tahun 2018 di Bulan Juni sebesar 15,84 mm dapat menghasilkan energi listrik sebesar 173,593 kWh dan terendah di Bulan Juli sebesar 0,86 mm dapat menghasilkan energi listrik sebesar 49,772 kWh dengan rata-rata pertahun 2018 yaitu sebesar 8,9592 mm di tiga stasiun. Sedangkan data debit air pada tahun 2018 tertinggi di Bulan Februari sebesar 10,08 m3/detik dapat menghasilkan energi listrik sebesar 198,296 kWh dan terendah di Bulan Juli sebesar 3,53 m3/detik dapat menghasilkan energi listrik sebesar 49,772 dengan rata-rata pertahun 2018 debit air sebesar 7,9858 m3/detik. Dengan rata-rata curah hujan 8,9592 mm dan debit air 7,9858 m3/detik dapat menghasilkan energi listrik rata-rata pertahun 2018 sebesar 156,0105 kWh selama tahun 2018. Dapat disimpulkan curah hujan tidak berpengaruh langsung terhadap produktivitas energi listrik yang dihasilkan sedangkan debit air berpengaruh terhadap produktivitas energi listrik.

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Development of Temporal Rainfall Pattern for Southern Region of Sarawak

Journal of Civil Engineering Science and Technology ◽

10.33736/jcest.98.2012 ◽

2012 ◽

Vol 3 ◽

pp. 17-23 ◽

Cited By ~ 1

Author(s):

Rosmina A. Bustami ◽

Nor Azalina Rosli ◽

Jethro Henry Adam ◽

Kuan Pei Li

Keyword(s):

Temporal Pattern ◽

Rainfall Intensity ◽

Peninsular Malaysia ◽

Southern Region ◽

Rainfall Pattern ◽

Rainfall Duration ◽

Design Rainfall ◽

Average Rainfall ◽

Urban Storm ◽

Australian Rainfall

In the process of a design rainfall, information on rainfall duration, average rainfall intensity and temporal rainfall pattern is important. This study focuses on developing a temporal rainfall pattern for the Southern region of Sarawak since temporal pattern for Sarawak is yet to be available in the Malaysian Urban Storm Water Management Manual (MSMA), which publishes temporal pattern for design storms only for Peninsular Malaysia. The recommended technique by the Australian Rainfall and Runoff (AR&R) known as the ‘Average Variability Method’ and method in Hydrological Procedure No.1-1982 are used to derive design rainfall temporal pattern for the study. Rainfall data of 5 minutes interval from year 1998 to year 2006 for 7 selected rainfall stations in the selected region is obtained from Department of Irrigation and Drainage (DID). The temporal rainfall patterns developed are for 10 minutes,15 minutes, 30 minutes, 60 minutes, 120 minutes, 180 minutes and 360 minutes duration. The results show that Southern region of Sarawak has an exclusive rainfall pattern, which is different from the pattern developed for Peninsular Malaysia.

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Evaluation of Dimensions and Drainage Performance Office in the Aceh Tamiang Area Kuala Simpang

Britain International of Exact Sciences (BIoEx) Journal ◽

10.33258/bioex.v3i1.355 ◽

2021 ◽

Vol 3 (1) ◽

pp. 20-32

Author(s):

Kamaluddin Lubis

Keyword(s):

Channel Capacity ◽

Discharge Capacity ◽

Return Period ◽

Rainfall Intensity ◽

Drainage Channel ◽

Flood Discharge ◽

Discharge Plan ◽

Runoff Discharge ◽

High Degree

The Aceh Tamiang office area is one of the office areas in Kuala Simpang which consists of various offices in the Aceh Tamiang area. The purpose of this research is to identify the drainage condition of the existing primary drainage channel which accommodates runoff discharge, the shape and direction of the flow in the inundation channel in the Aceh Tamiang Kuala Simpang office area, which is expected to help solve the problem of flooding in the 832 m3 / second. And for the channel capacity in this primary drainage drainage of 0.829 m3 / sec, the value is smaller than the planned flood discharge (Qr). Rainfall intensity (I) of 126,432 mm / hour. The plan flood discharge (Qr) for a 5-year return period yields 2,551 m3 / second and the value for channel discharge capacity (Qs) is obtained from the calculation of 2,216 m3 / second. This value is smaller than the value of the planned flood discharge.area. From the results of research conducted by the Aceh Tamiang Kuala Simpang office area is a location with a fairly high degree of rainfall, with a rainfall intensity (I) of 126,432 mm / hour and a flood discharge plan for a 5-year return period obtained a result of 0.

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