monsoon season – Meghalaya PCS Free Notes

Rivers and drainage system of Meghalaya

One of the world’s wettest regions is found in Meghalaya. Mawsynram and Cherrapunji (Sohra) in the East Khasi Hills district are geographically considered as the rainiest places in the World. — Cherrapunji, which has an average annual precipitation of about 11,430 mm (450 inches) during monsoon season (from May to September) and Mawsynram, a village directly west of Cherrapunji, where rainfall of around 17,800 mm (700 inches) per year has been recorded. The area receives rainfall on an average for 160 days in a year, spread over 6 to 8 months from March to October.

Physiographically, Meghalaya represents a remanant of an ancient plateau of Pre-Cambrian Peninsular shield, block lifted to its present height and is referred as Meghalaya Plateau or as Shillong-Mikir massif. It is the detached northeastern extension of Indian Peninsular shield, part of which lies beneath the alluvium deposited by Ganga Brahmaputra system of rivers. The rivers of the State are rainfed and therefore their discharge dwindles during summer. Important rivers in Garo Hills region are Daring, Sanda, Bugi, Dareng and Simsang. In the central and eastern part of the plateau are Umkhri, Digaru, Umngot and Myntdu rivers.

The surface water resource is tapped in a number of places by constructing dams across the rivers. The reservoirs, like the Umium and Kopili, so developed are not only used for irrigation and drinking water but also for generating electricity. Inspite of this, the area experiences shortage of water during the summer resulting in crisis for drinking water. This is mainly due to topographical and geomorphological conditions apart from alterations of the natural land surface by way of development, mining and urbanization.

Moreover, the characteristic hilly and steep sloping terrain condition in the area with localized small valleys results in very high surface run-off during the monsoon.

Some of the important rivers of Meghalaya are as follows:

Digaru

Digaru is a river originating in the Garo-Khasi hills of Meghalaya state in India, flowing towards the northeast and then meeting the Kolong river and then merging with the Brahmaputra river. The name Digaru originated from a Kachari/Mech word ‘Di’ which means water and ‘Garo’ means the people living in the Garo hills. Hence Digaru literally means “water of the Garo”.

Kopili River

The Kopili originates in the Meghalaya plateau and flows through southern Assam before its confluence with the Brahmaputra. In Assam it drains the districts of Karbi Anglong, Dima Hasao, Kamrup and Rivers and drainage system of Meghalaya Nagaon. The river flows for a total length of 290 kilometres (180 mi) and has a catchment area of 16,420 square kilometres (6,340 sq mi). It is noted for several spectacular waterfalls along its course which has several deep gorges and rapids in the 120 kilometres (75 mi) of its flow before debouching into the plains at Nagaon district.

Myntdu River

Myntdu River is one of the major water bodies in Jaintia Hills District, Meghalaya, locally known as ‘ka Tawiar ka Takan’ (Our Guardian Angel) in the Pnar dialect. It is a blessing to the residents of the town of Jowai and adjacent places. Its abundant water is used to irrigate the Myntdu Valley, located on the outskirts of Jowai town. The river, originating at 1,420 metres (4,660 ft) above sea level, is fit for hydro-power development.

The river flows across Jowai, and then through Leshka (where a Hydro Project Dam is being constructed) to reach a village Borghat, within Jaintia Hills, before finally entering Bangladesh, where it is locally called ‘Shari’.

Piyain River

Piyain River a trans-boundary river of India and Bangladesh. It is a tributary of the Surma river, which is originates from the Umgat river of Assam. The river enters Bangladesh through Sylhet district. The length of the river is 145 km. Piyain river has emerged from the river om or Umagat river or Assam.

Someshwari River

Someshwari River, known as Simsang River in the Indian state of Meghalaya, is a major river in the Garo Hills of Meghalaya and Netrakona District of Bangladesh. It divides the Garo Hills into two parts.

Natural hazards and related issues of Meghalaya

As the State lies in the seismically active zone, special emphasis should be given to reduce the impacts of earthquake. Moreover, it is also affected by hazards such as floods, flash floods, epidemics, fire, hailstorm, lightening, road accidents, etc.

Earthquake

The State of Meghalaya has witnessed seismic events of ‘8.7 magnitude in 1897’. This region has been identified as a potential site of a future catastrophic earthquake. With the growth of population and infrastructure seismic vulnerability has increased and previous earthquakes have provided a glimpse of the devastating potential of seismic tremors.

Cyclones

Meghalaya is situated in the north eastern direction of Bangladesh which is highly prone to cyclone/ winds. Every year about 60% of the area is affected by cyclone in Bangladesh. The Districts of West Jaintia Hills and East Jaintia Hills may experience a wind speed of up to 55m/s. Occasional cyclones do occur in western Meghalaya their severity being more during monsoon season. The Districts close to Bangladesh like South West Garo Hills, South Garo Hills, South West Khasi Hills, West Khasi Hills, fall in very high cyclonic zone due to close proximity to Bay of Bengal (which is a cyclone basin). In this zone wind speed can reach up-to 50 m/s, which can cause large scale damages. The Bay of Bengal accounts for seven percent of the annual tropical cyclone activity worldwide; the recorded frequency of cyclones per year along the Bay of Bengal is four and inevitably one of the four transforms into a severe cyclone causing human and property losses

Floods

The State with hilly terrain does not suffer from a major problem from floods, However, due to heavy rain, flash floods may be caused resulting in river bank erosion and some local damage. In Meghalaya, Natural hazards and related issues of Meghalaya floods occur in river valleys, when flow exceeds the capacity of the river channel, particularly at bends or meanders. The plain areas of Meghalaya adjoining Assam are affected by flood due to the back flow of water from the River Brahmaputra during the flood season between June and October. The tributaries like Krishnai, Jinari, Jingjiram, Rongai, Dudhnoi, Ringgi, Gohai, Dilni etc cause flood in the plain areas of the State.

Landsides

Meghalaya being a hilly terrain is prone to landslides. Every year a number of landslides have been reported from various localities. These cause a lot of miseries to public, resulting in loss of lives and properties, disruption of communication network, besides causing economic burden on the society. Landslide is primarily attributed to high slope, immature geology, neo-tectonic activity, heavy rainfall, unplanned and improper land use practice in the State. Landslides generally occur during heavy rains, that is during the months of June to October in Meghalaya.

Southern part of Meghalaya is more susceptible to Landslides than the Northern Part. National Highways like Bajengdoba-Tura-Dalu, Damra–Siju-Baghmara, Guwahati – Shillong- Tamabil, and Shillong- Jowai- Badarpur are prone to landslides.

Landslide occurred frequently at Sonapur on Shillong- Jowai- Badarpur Road, but now the problem has been mitigated by constructing a tunnel for the vehicular traffic. Urban areas of Shillong and Tura, Jowai are also prone to landslides due to the faulty Construction of Houses and rapid Urbanization.

Lightning and Hailstorms

Lightning occurs during the monsoon months and can strike at any place. Hailstorm generally occurs in the pre and post monsoon months. Some loss of crops lives and properties due to lightning and hailstorms are reported in the state.

Hazard Specific Mitigation Plan

The State Disaster Management Authority was established in the State under the Chairmanship of the Chief Minister with 8 other members under section 14 of the Disaster Management Act, 2005 by a Government notification dated 26th June, 2008. It is the apex body for disaster management in the State.

The State Executive Committee headed by the Chief Secretary with 4 other Secretaries as members was also set up to assist the State Disaster Management Authority in the performance of its functions.

The District Disaster Management Authorities under the Chairmanship of the Deputy Commissioners and Chief Executive Members of the District Councils as Co-Chairmen with 5 District Officials as members were also set up for the better management of disasters in the Districts.

Similarly at the Block and Village levels Block Disaster Management Committee and the Village Disaster Management Committee were set up headed by the respective Block Development Officers and the Village Headmen. The State Disaster Management Authority, has set uMock drill by NGO’sMock drill by NGO’sp a State Disaster Management Secretariat in 2010 which is located in the Office of the Director of Land Records and Surveys, Lower Lachumere, Shillong. The day to day functioning of the SDMA is looked after by the Executive Officer of the Secretariat.

Functions of SDMA

Framing of Disaster Management Policy and the preparation of the State Disaster Management Plan, reviewing the preparedness, prevention, mitigation and capacity building measures in the State.

Activities of SDMA

The preparedness, prevention, mitigation and capacity building programmes.

The Disaster Risk Reduction Project funded by the UNDP which focuses on the awareness programmes, capacity building, strengthening of the disaster management institutions are being implemented in the three districts of East Khasi Hills. West Garo Hills and the Jaintia Hills, While the Urban Risk Reduction Programme is being implemented in the capital city Shillong through the SDMA Secretariat the Capacity Building Programme is under the 13th Finance Commission. Besides, Hazard Risk Vulnerability Assessment (HRVA) will also be carried out for the Shillong city and the West Garo Hills through North Eastern Space Application Centre, Umiam.

State Disaster Response Fund is available for management of disasters in the State. An advance amount from the fund is made available to the Deputy Commissioners to meet any emergency arising out of disasters.