Effective engineering solutions can mitigate the ongoing flood and landslide crisis in India

India is a witness to diversity not only in terms of its culture and heritage but also in its climate across all regions. While some states see extreme climate from scorching summers to freezing winters like Delhi, others have heavy rainfall and humidity like the coastal regions. Different borders come with a set of different weather woes as well.

In the recent years, India has seen a significant rise in extreme precipitation events. Driven by unplanned urban growth, environmental degradation and rising temperatures, the resulting nationwide calamities like floods and landslides have forced millions to flee their homes causing widespread damage to life and property.

Monsoon’s sweet relief laced with apprehensions: A view on the recent floods and landslides in India

Days of hefty monsoon downpour triggered flooding along with several landslides in north Indian states. Cloudburst in Himachal Pradesh, Uttarakhand, Jammu and Kashmir, and Ladakh killed at least 17 people, damaged several residential houses, bridges and a mini hydro-power plant. Yamuna River in Delhi breached the danger mark issuing a flood alert with expedited efforts to evacuate people living in the area.

The damage was equally menacing for the southern states as well. Nine people died and hundreds were evacuated in states of Telangana and Goa due to flash floods. Approximately 76 people lost their lives amid recent landslides and floods in parts of Maharashtra. With rescue and relief measures still underway, about 90,000 people have been evacuated across the 9 districts of the state.

Eastern states were not far behind, the havoc caused due to extreme rainfall in Assam flooded 90% of the districts putting more than 50,000 people in relief camps. Additionally, over 100,000 people in eight districts in north Bihar have been affected since last year.

What’s costing Indian states so much damage?

There are several causes of floods and landslides that differ from region to region. The reasons may vary from a rural to an urban area. It is common to mistake heavy rainfall and overflowing of riverbanks as the only causes of floods in our country. However, recent studies show that this is far from true.

Rising global temperatures due to climate change, speeding up the glacier melt (Himalayan region in India) has led to a shift in the weather patterns. Not to forget the same is also projected to swell up the flow rates in the Ganges and Brahmaputra rivers and as a trickledown effect threatening damage to livelihood with floods, landslides, and cloudbursts.

Loss of green cover is another reason to worry about. With rapid deforestation activities across the country, there is nothing left to hold together the soil at the flood prone regions. This increases the risk of landslides exponentially.

Unchecked or ill-planned urban development cannot be ignored as well. Grazing down of mountains and hills (Himalayan ranges are a fragile ecosystem), improper drainage systems in cities, especially the metropolitans, have recently cropped up as a factor causing chaos in the monsoon season.

There is a need for proactive planning & budgeting for hazards like landslides and rockfall. At the conceptual/feasibility stage of any infrastructure development these aspects must be considered which will save precious human life, valuable infrastructure and avoid inconvenience.

Some solutions to the hazard

Recognizing the vulnerable areas to flood, landslides, rockfall regions and slope instability should be one of the initial focuses.

More structural solutions require mitigating hydro-geological problems such as debris flows or shallow landslides. Using dynamic barriers, reinforced soil embankments can avert the dangers of an outburst and resultant flooding.

Next, protection of the newly exposed vulnerable soil is very important to prevent topsoil run-off into watercourses as well as debris flows. Erosion control mats can be deployed to protect soils whilst improving conditions for vegetation regrowth.

Advanced economical and effective solutions to rockfall regions as well as slope stabilization solutions can be beneficial from commercial, and eco-friendly points of view. The protection measures for such hazards are covered in the Indian Road Congress guidelines and these need to be practiced. Technological measure can also include an alert system to monitor rockfall protection. The system can send timely alerts not only when a rockfall event occurs but also on the status of the rockfall protection ensuring safety, reliability, and accuracy.

Preventing watercourse from getting overtopped and flooded in the first place with watercourse design software solutions that works through a great river channel design along with the inclusion of appropriate hydraulics, can be a helpful preventive tool.

For areas with improper drainage systems, and erosion caused by a flowing river coupled with an intense monsoon, using geosynthetics during construction of drains can be the answer to distresses of people in the flooded cities of India.

A good case in point of a holistic implementation was provided by us for the Lambagarh landslide region. A system of solutions was provided at the site of the Lambagarh landslide which receives a large number of visitors. It is located on the road (NH-58) and leads to the holy shrine of Badrinath in Uttarakhand. The solution included construction of a flexible reinforced soil wall with gabions as facia and high strength geogrid as reinforcement towards the valley side for shifting the road from its current position.

Sustainable measures that are immediate and long lasting in nature is the need of the hour for the current floods and landslides crisis in India. It’s important to note that while relief measures are crucial during disaster management, it’s the preparedness that ultimately results in reducing the risk to lives and property in the long run.

The author is the Managing Director of Maccaferri in India and the Regional CEO of the ISEAP region at the Officine Maccaferri Group.

(Disclaimer: The views expressed above are the author's own and do not reflect those of DNA.)