Social and Environmental Consequence of Highways & their Mitigating Measures

 

Highways provides both positive & negative impact to the people and society. It benefits by providing mobility and reducing the commuting time, whereas on the negative side, it causes environmental degradation through pollution, land use and some social obstacles. It may create dislocation of society, damage to cultural heritage. Social consequences are related to human dimension of environment and seeks to identify the impact on people. Major type of social impacts is related to lifestyle, cultural, community, quality of life & health related impacts. Environment consequences are related to environmental factors on air quality, water, noise, biodiversity, ecosystem, land stability etc. It is inevitable to identify social and environmental impact and consequences of construction & operation of highways during planning phase. The mitigation plan should be prepared and implemented to reduce the impact and consequences of highways to society & environment.

Social & Environment consequences are:

a. Demographic process- Migration, seasonal residents, displacement, influx and outflux of workers 

b. Economic process- Inflation, currency fluctuation, export/import, employment, economic globalization

c. Geographic process- Change in land use pattern, formation of city, industrial area, residential area, urban sprawl, Urbanization, gentrification, enhanced transportation and rural accessibility.

d. Institutional and legal process- Institutional globalization & centralization, Decentralization, Privatization.

e. Emancipator and empowerment process- Democratization, Marginalization, Capacity building.

f. Socio-Cultural Process- Social globalization, segregation, social integration, cultural differentiation.

g. Environment process- Air quality, sound pollution, water pollution, soil erosion, ecosystem, biodiversity, flood, landslide.

Positive Social Impacts

a. Income opportunities for local labor- During Construction phase

b. Income opportunities for contracting firms & consulting firms- During construction phase

c. Creation of job opportunities for local region & wider region- During construction phase and operation phase

d. Time saving- During operation phase

e. Reduction of Vehicle operating cost- Operation phase

f. Accident reduction- Due to better roads during operation

g. Better level of service

h. Financial benefits due to regular toll revenue

i. Improvement of road infrastructure

j. Regional balance & equality

k. Connectivity and social integration

l. Positive externalities like development of city, Urbanization.

Negative impacts

a. Land acquisition- During pre-construction/planning phase

b. Possibility for accidents and safety risk- During construction and operation phase

c. Sound pollution- During construction & operation phase

d. Air & water pollution- During construction & operation phase

e. Migration- During operation phase

f. Increase in land value

g. Need of resettlement

Mitigation plan for social impacts

a. Compensation on land acquisition- During Planning phase

b. Resettlement plan- During planning phase

c. Risk assessment & Identification- During planning phase

d. Quality construction material- during construction

e. Lean construction method- during construction phase

f. Safety, supervision- During construction & operation phase

g. Regular maintenance, rehabilitation, safety structures- during construction & operation phase

h. Communication with local people about timing of explosive activities and other construction activities

i. Appropriate right of way, drainage, bridge

j. Control of dust during construction

Environmental impacts 

a. Public health and safety- Mainly during construction phase

b. Accessibility- Can restrict access to community facilities like water source, forest etc.

c. Land stability- land collapse, landslides, soil erosion

d. Sedimentation- Increased sediments near shore

e. Air quality- Air borne dust

f. Noise pollution- During construction and operation phase

g. Land surface disturbance- Due to vibration during construction and operation phase

h. Deforestation- Use of forest area

i. Disturbance to wildlife

j. Ecosystem imbalance

k. Disaster- landslide, flood

l. Accident hazards

m. Aesthetics & landscapes

Mitigation Measures

a. Maintaining moisture during road construction can reduce dust pollution

b. Construction of overhead and under head structures to provide accessibility for people and wildlife. Green overhead/under head structures for wildlife crossing in forest area.

c. Providing structures like retaining walls, revetment wall, gabion walls according to the site requirement to stabilize the slope.

d. Slope protection works like bio- engineering, vegetation in berms of embankment etc.

e. Construction of cross drainage structure, maintenance and cleaning to protect from flood.

f. Providing structures in bridge to control sedimentation and dredging. Protection against scouring.

g. Construction of green roads to preserve aesthetics and landscape of area.

For road transportation, construction of highway is necessary. It provides connectivity within wide range to people & society and reduces the travel time. It also has positive impact on economy of country and is directly related to living standard of people. However, it causes both positive and negative impact to the society and environment. With the help of proper planning and action, positive impacts can be enhanced, and negative impacts can be minimized. It is necessary to integrate environment impact assessment and social impact assessment along with the scope of project. Impact assessment should be carried during planning phase of the project and should identify the problems and mitigating measures. Mitigating activities should be carried out during construction period as well as operation period, and it should clearly define the responsibility of contractor, client and consultant and time frame of the activities to be carried out.