Challenges faced for Installation of Emergency Restoration System (ERS) in the Major Natural Disaster Hit High Voltage Transmission Lines in India

Tamil Selvan M. and Kodi Malar

Page No. 1-8

High Voltage Transmission lines are subjected to several natural disasters like earthquake, flood, landslides, hurricanes etc. Power line failure due to these scenarios makes a severe financial damage to consumers, utilities and the power producing agencies. Also, transmission line failures occur due to harsh weather and non-climatic reasons such as human errors and mechanical failures. While it is impossible to prevent all such situations, electrical utility officials and contractors have to be equipped to meet such emergencies.

Emergency Restoration System (ERS) structures are temporary solution designed to bypass the existing transmission towers of any voltage in any terrain. They will be used until the main line is re-conductored or restored. Planning includes determining which transmission lines are important and the possible ways in which they can fail and how best to restore them. This includes general information about existing structures and foundations, data on past weather-related failures, weather criteria and structural loading and the extent of damages. In this study, we are analyzing various challenges faced due to the major transmission lines failures in India during various past natural disasters. Supply of continuous power will be the most important aspect of a transmission line network during emergency time.

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Drivers of Natural Hazards Vulnerability in Urban Waterfront of Alexandria, Egypt

Tawfik Sahar, Ragab Tarek and Darwish Mennatallah

Page No. 9-14

Natural hazards are a serious threat to urban areas with a heavy concentration of population growth and economic activity along with a fast rate of unplanned urban development. Extreme events expose Alexandria highly to potential adverse consequences that lead to considerable damage and loss of natural and cultural heritage. Climate change combined with many complications such as land subsidence and informal settlements, have adverse effects on its coastal areas.

The evaluation of the city’s vulnerability to such implications shows a gradual increase in marine submersion risk and coastal erosion. This study aims to identify the relation between the city’s characteristics and document its vulnerabilities to provide a tool for urban planning. The results reveal a gradual increase of coastal resource’s vulnerability highlighting the importance of the formulation of the appropriate adaptation strategies and approaches.

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Comparing Seismicity Parameters for Different Seismic Zones in Warangal

Mohammad Muzzaffar Khan and Gonavaram Kalyan Kumar

Page No. 15-25

In this study, the spatial variation of b-value has been investigated to identify the frequency of a particular magnitude earthquake to occur. The study area is considered for a radius of 500 km with NIT Warangal as centre (lat. 17.591 and long. 79.533). The earthquake data for the period from 1800 AD to 2016 AD is used in the analysis. The b-value has been calculated for two scenarios. In the first scenario, the whole study region is considered as one seismic source zone whereas in the second scenario, the considered study region was divided into four seismic source zones. The b-value has been investigated by adopting the maximum likelihood method and least square method.

The magnitude of completeness (MC) was analyzed using Entire Magnitude Range (EMR) technique in ZMAP software package. The maximum magnitude (mmax) has been estimated for each seismic zone using the Kijko-Sellevoll-Bayes procedure. Significant variations in seismicity parameters have been observed in four seismic zones. The b-value is ranging from b ≈ 0.7 to 1.13 whereas the mmax value ranges from 5.18 to 6.65. This data can be used in further research to develop a higher understanding of the earthquake hazard at the regional level.

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Performance of Flood Prediction Model in Tropical River Basin, Indonesia: A Synthetic Unit Hydrograph-based Evaluation

I. Gede Tunas

Page No. 26-37

The major issue in flood mitigation scheme is how to predict the flood peak in a region based on a certain rainfall event. Many approaches have been developed including rational, statistical, empirical and synthetic unit hydrographs (SUH) models. This study aims to evaluate the performance of flood prediction models especially SUH-based models. This study was carried out in six medium-sized watersheds based on the eight most popular synthetic hydrograph models in Indonesia comprising Snyder, Nakayasu, Soil Conservation Service (SCS), GAMA I, ABG, Limantara, ITB-1 and ITB-2. The performance of these models was evaluated by comparing the basic parameters of synthetic unit hydrographs with the basic parameters of the observed unit hydrographs expressed by relative error. The Nash-Sutcliffe Efficiency (NSE) and the coefficient of determination (r2) were also applied to measure the performance of the models.

The results revealed that the eight evaluated SUH models showed performance with varying levels of deviation mostly above 30% and NSE and r2 values mostly below 0.8. Based on the average deviation of the three basic hydrograph parameters (Qp, Tp and Tb), the best-performing SUH models were ITB-1 for Qp (15.6%), Limantara for Tp (3.9%) and ABG for Tb (20%). Based on NSE and r2, the SUH model with the best performance was Limantara (NSE=92; r2=0.95). The best performance of the model is expressed by the highest score of the five indicators. Based on all those indicators, it can be inferred that the GAMA I is the most accurate model with the highest score of performance in the study area. This model can be applied for flood prediction in other unmeasured watersheds in Indonesia with similar morphometric characteristics.

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Analysis of Long-term Extreme Weather Events and Prediction of Natural Disaster-Prone Regions of the Himalayas using PRECIS Regional Climate Model (RCM)

Tamil Selvan M.

Page No. 38-46

Himalayan region is the source of ten major Asian rivers, so the region is called as the Water Tower of Asia. With high elevations and holding large mass of ice and debris cover, Himalayan region has been recognized as one of the most fragile areas susceptible to climate change effects. Last decade reported highest number of disasters and greater spatial coverage as compared to the earlier decades. In this study, analysis of various climatic datasets has been done over period of time. From the long-term analysis, various extreme weather events have been identified based on their intensity and classified accordingly.

In this study, high-resolution regional climate model (RCM), PRECIS (Providing Regional Climates for Impacts Studies) is used to project future climate scenario over the Himalayan region for impact assessment. PRECIS model was analyzed by comparing its baseline simulation daily weather data on temperature and precipitation patterns with other observed weather data for the corresponding period in order to find out the bias in the model. The result shows that the western regional disturbances will become more frequent, elevating the probability that winter snowfall in the Karakorum and western Himalayas will increase in frequency and amount.

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A Review on the Response of Mangroves to the Climatic Changes

Srinidhi N.S., Lingaswamy Manchala and Anji Reddy M.

Page No. 47-51

Mangroves at the coastal frontier are being degraded at an alarming rate due to their ecological and economical importance. “A world without Mangroves” article has clearly stated that every year about 1 to 2%, a rate greater than or equal to declines in the coastal areas. The major factors contributing for the loss and degradation are underestimating the total economic value and the human impacts. The loss of mangroves can affect biodiversity, environment and the livelihood of the people depending on them. The various factors of natural and anthropogenic factors contributing to the degradation of mangroves are natural disasters, urbanization, aquaculture, agriculture, tourism and environmental pollution.

Other effects like global warming, rising water due to the melting of the ice caps, climate change, ocean currents, salinity and surface temperatures could be significant threats to mangrove cover and biodiversity. Mangrove area, structure and species composition of mangroves are expected to alter in the position due to climatic changes. The present study discusses on the response of mangroves to the climatic changes and the alternatives for mitigating the adverse effects.

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