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The project “Micro Landslide Hazard Zonation Mapping of Lunglei Town using Remote Sensing and GIS” was undertaken by the Mizoram Remote Sensing Application Centre (MIRSAC), Science & Technology, Planning Department, Government of Mizoram, as an in-house study to support disaster-risk reduction and safer urban development in Lunglei. The study was initiated in response to recurrent landslides associated with the town’s steep and dissected terrain, weak sedimentary formations, heavy monsoon rainfall and increasing anthropogenic disturbances such as road cutting, slope modification and unplanned construction. Its main objectives were to analyse land use/land cover, slope, geomorphology, lithology and geological structure, and to integrate these parameters for preparation of a micro-level landslide hazard zonation map.The study covered the 55.08 sq. km notified area of Lunglei Town. High-resolution QuickBird imagery with 0.8 m spatial resolution formed the primary database, supplemented by IRS-P5 Cartosat-I stereo imagery of 2.5 m resolution, Survey of India topographic maps, field observations and ancillary information. Cartosat-I stereo data were used for contour and slope generation, while QuickBird imagery supported detailed thematic interpretation. The hazard assessment adopted a qualitative, expert-weighted methodology modified from the NRSA approach, in which the controlling terrain parameters were rated according to their relative influence on slope instability.The terrain analysis revealed the dominance of steep slopes: 55.41% of the study area lies within the 40–60° slope class, while another 33.60% falls within 20–40°; only about 9% of the area has slopes below 20°. Geomorphologically, Medium Structural Hills occupy 71.94% of Lunglei, followed by Low Structural Hills at 21.18%, demonstrating the strong structural control over the town’s rugged landscape.The final landslide hazard zonation classified Lunglei into five susceptibility classes. Very High Hazard Zones occupy 1.01 sq. km (1.84%), while High Hazard Zones account for 7.67 sq. km (13.92%). The largest proportion falls within the Moderate Hazard Zone—19.76 sq. km or 35.87%—followed by Low Hazard at 17.05 sq. km (30.96%) and Very Low Hazard at 9.59 sq. km (17.41%). Thus, approximately 51.6% of the town falls within Moderate to Very High hazard categories, highlighting the significance of terrain instability for future urban planning.The study also documented field evidence of slope instability associated with crumpled shale, jointed rock, quarrying, road widening, retaining-wall failure and soil saturation. Overall, the project demonstrated the effectiveness of high-resolution Remote Sensing and GIS for micro-level landslide assessment. The resulting thematic layers, hazard zonation map and 1:20,000 grid-wise maps provide an important scientific baseline for land-use regulation, infrastructure planning, slope stabilization, disaster preparedness and prioritization of mitigation measures in Lunglei Town.Summarized MetadataMapping Scale: 1:5,000 Satellite data & Year: Quickbird & Cartosat-1 (2007)Thematic sub-category: Disaster Management, GeologyCollaborating/Funding Agency: Science, Technology & Environment Wing, Planning Department, Government of MizoramReport Publication Month/Year: February, 2009

The project “Micro Landslide Hazard Zonation Mapping of Aizawl City using Remote Sensing and GIS” was undertaken by the Mizoram Remote Sensing Application Centre to produce a detailed spatial assessment of landslide susceptibility within Aizawl City. The study was initiated in response to recurrent slope failures, rapid urban expansion and increasing development pressure on the city’s narrow ridges and steep hill slopes. Its principal objective was to identify areas of varying landslide hazard, analyse the major causative factors influencing slope instability and provide a scientific basis for safer land-use planning, infrastructure development and disaster-risk mitigation.The study covered the entire Aizawl urban area of 128.98 sq. km. High-resolution QuickBird imagery with 0.8 m spatial resolution was used as the primary dataset, supplemented by IRS-P5 Cartosat-I stereo data at 2.5 m resolution, Survey of India topographic maps, field observations and GPS-based ground verification. Five principal thematic parameters—land use/land cover, slope, geomorphology, lithology and geological structure—were generated and integrated in ARC/INFO GIS using a weighted heuristic approach. Additional consideration was given to active and old landslides, fault proximity, road cutting, drainage conditions and dip-slope relationships. The final hazard maps were prepared at 1:5,000 scale, with grid-wise reference maps also produced at 1:20,000.The results demonstrate the inherent fragility of Aizawl’s terrain. About 64.22% of the city lies on slopes exceeding 40°, including 63.95% within the 40–60° class, indicating that steep terrain is the dominant physical constraint. Scrubland forms the largest land-use category, occupying 52.51 sq. km or 40.71%, while built-up areas already cover 18.23 sq. km or 14.13%. Geomorphologically, medium and low structural hills together account for more than 96% of the study area, whereas valley fills occupy only 0.28%, confirming the scarcity of naturally stable flat land. Lithological analysis shows that sandstone covers 39.41%, while crumpled shale and shale-sandstone units together occupy over 45%, creating extensive zones of relatively weak and weathering-prone material.The hazard zonation classified the city into five categories. Very High and High Hazard Zones together cover 37.77 sq. km, or 29.28% of the city, representing areas where construction and major development require avoidance or stringent geotechnical scrutiny. The Moderate Hazard Zone is the largest class at 56.66 sq. km (43.93%), while Low and Very Low Hazard Zones account for 20.61% and 6.18%, respectively. High-risk locations were associated with active landslides, faults, crumpled shale, steep road cuts, quarrying, poor drainage and dense settlement.The project’s principal outcome is a detailed GIS-based hazard database for Aizawl City. It provides planners, engineers, municipal authorities and disaster-management agencies with an operational tool for site selection, building regulation, road and drainage design, slope stabilization, emergency planning and hazard-sensitive urban development. Summarized MetadataMapping Scale: 1:5,000 Satellite data & Year: IRS P5 Cartosat-I & Quickbird (2006)Thematic sub-category: Forestry, Administrative boundaryCollaborating/Funding Agency: Science, Technology & Environment Wing, Planning Department, Government of MizoramReport Publication Month/Year: March, 2008

The Report on Landslides in Mizoram, prepared by the Mizoram Remote Sensing Application Centre (MRSAC) under the Science and Technology Wing, Planning Department, Government of Mizoram, was compiled in 2007 in response to the increasing incidence of landslides and associated disruptions across the State's mountainous terrain. The study was undertaken to document recent landslide occurrences, assess their geographical distribution and impacts, and provide an initial scientific understanding of landslide susceptibility across Mizoram, particularly following intense monsoon rainfall during September 2007.The project employed Remote Sensing and Geographic Information System (GIS) techniques to prepare a generalized Landslide Hazard Zonation (LHZ) map for the State. IRS-1D LISS-III satellite imagery acquired in February 2003, together with Survey of India topographic maps at 1:50,000 scale and available ancillary spatial datasets, was used to analyse terrain and geo-environmental conditions. Key causative parameters—including lithology, geological structure, geomorphology, slope, and land use/land cover—were integrated using ARC/INFO GIS software to classify Mizoram into five relative landslide hazard categories. The analysis provided a statewide framework for identifying areas of varying susceptibility and understanding the influence of both natural terrain conditions and human interventions such as road cutting and quarrying.The report also compiled field and administrative information on landslide impacts from across all eight districts of Mizoram, documenting damage to houses, roads, bridges, public utilities, and communication networks. The assessment highlights the vulnerability of settlements and infrastructure during periods of intense rainfall and demonstrates the widespread nature of landslide-related hazards in the State.A key outcome of the project was the preparation of a generalized Landslide Hazard Zonation Map of Mizoram, providing an important baseline for disaster preparedness and mitigation. The report emphasizes that although landslides cannot be completely prevented, their impacts can be reduced through appropriate land-use planning, slope stabilization, safer infrastructure development, and avoidance of highly susceptible areas.The resulting landslide inventory, hazard zonation map, spatial information, and documented observations provide valuable reference material for government departments, disaster management authorities, planners, engineers, researchers, and local administrations. The information can support road and infrastructure planning, hazard monitoring, emergency preparedness, environmental management, and prioritization of mitigation measures, while also providing a foundation for more detailed, site-specific landslide susceptibility and risk assessments in the future.Summarized MetadataMapping Scale: 1:50,000 Satellite data & Year: IRS 1D LISS III (2003)Thematic sub-category: Landslide, Disaster ManagementCollaborating/Funding Agency: Mizoram Remote Sensing Application CentreReport Publication Month/Year: September, 2007

The Vulnerability Analysis of Cyclone in Mizoram State was executed by the State Remote Sensing Centre (SRSC), Science, Technology & Environment Wing, Planning Department, Government of Mizoram, Aizawl. Stemming from a Hazard Mapping meeting on April 13, 2004, chaired by the Secretary, Relief & Rehabilitation, the project was funded by the Relief & Rehabilitation Department., Government of Mizoram.Covering Mizoram (21,087 sq km) strategically bordered by Bangladesh (west) and Myanmar (east/south), featuring NNW-SSE trending ridges with humid tropical climate (250–350 cm annual rainfall and temparatures ranging from 11–31°C, the study analyzed cyclone impacts using 20-year records (1985–2004) from eight districts (Mamit, Kolasib, Aizawl, Champhai, Serchhip, Lunglei, Lawngtlai, Saiha) and 2001 Census data.​The methodology integrated IRS LISS-III FCC visual interpretation, SOI topographical maps for physiographic parameters (location: ridge/hill-top/slope/valley; aspect: N/NE/E/SE/S/SW/W/NW; altitude: 0–500/501–1,000/>1,001 m), and ArcInfo GIS for vulnerability zoning: low (0–3 events), medium (4–6), high (≥7). Of 828 villages/towns/wards, 450 (54.4%) were low vulnerability, 243 (29.3%) medium, and 135 (16.3%) high.​District-wise observation and analysis showed that Saiha topped high vulnerability (23/77 wards; 29.87%), followed by Lunglei (52/185; 28.11%), Lawngtlai (16/139; 11.51%), Champhai (12/85; 14.12%), Aizawl (15/160; 9.38%), Kolasib (11/52; 21.15%), Mamit (4/87; 4.6%), Serchhip (2/43; 4.65%). Locationally, ridge/hill-tops dominated high vulnerability (e.g., 82.69% in Lunglei; 93.33% in Aizawl), vs. slopes (20.17% overall) and valleys (18.24%). Altitude-wise, high vulnerability peaked at 501–1,000 m (56/135; 41.5%) and >1,001 m (45; 33.3%). Aspect vulnerabilities varied throughout the locations e.g., NW highest in Lunglei (23.07%), E in Kolasib (54.55%). Cyclones (post/pre-monsoon tails from Bay of Bengal; est. Saffir-Simpson scale 2–3: 43–58 m/s) caused house/powerline/road/crop/livestock damage, exacerbated by Assam-type/thatched/tin-roof structures on exposed saddles/ridges.​The project produced thematic maps, tables (village/ward/district/aspect/altitude-wise), and a cyclone database, marking SRSC's first disaster management effort. Outputs enable risk-based planning: prioritize retrofitting high-vulnerability ridge-tops (>501 m), enforce cyclone-resistant designs (sloping roofs at 33:10, J-bolts/anchors/bracing/bands, leeward sites, windbreaks like tree belts), avoid saddles/protrusions, and integrate into mitigation cycles (preparedness/response/recovery).​Recommendations from the project outputs emphasize wind-loading standards, RCC slabs, reinforced walls/frames, minimal projections, and firm foundations against torrential rains, fostering resilient infrastructure amid Mizoram's frequent moderate cyclones.​Summarized MetadataMapping Scale: 1:50,000Satellite data & Year: IRS LISS III (2003)Thematic sub-category: Disaster managementCollaborating/Funding Agency: Relief & Rehabilitation Department, Govt. of MizoramReport Publication Month/Year: December, 2004