[INFORMATIVE] The Increase of Concrete Roads and Its Effect on Groundwater

The Increase of Concrete Roads and Its Effect on Groundwater

By Mansi Kumbhare

What are Concrete Roads?
Concrete roads are made from a mixture of cement, water, sand, and aggregates such as gravel or crushed stone. This mixture hardens into a durable surface used for road construction. Concrete roads are known for their strength, longevity, and ability to withstand heavy traffic and adverse weather conditions. Here are some key features of concrete roads:

• Durability: Concrete roads have a long lifespan, often lasting 20 to 40 years or more without requiring significant maintenance.
• Strength: They are particularly good at supporting heavy loads, making them ideal for highways and areas with frequent truck traffic.
• Low Maintenance: Once laid, concrete roads require minimal maintenance compared to asphalt roads.
• Reflectivity: Concrete reflects more light, which can enhance visibility at night and reduce the need for street lighting.
• Heat Resistance: Concrete doesn't soften under high temperatures like asphalt, making it suitable for hot climates.

However, concrete roads can be more expensive and take longer to build than asphalt roads, and repairs can be more complex.

What is Groundwater?
Groundwater is the water that exists beneath the Earth's surface, filling the pores, cracks, and crevices in soil, sand, and rock layers known as aquifers. It is a critical component of the hydrologic cycle and is replenished through processes like rainfall infiltration and surface water seepage. Groundwater accounts for a significant portion of the Earth’s freshwater supply and is utilized for various purposes, including agricultural irrigation, industrial processes, and drinking water. This water can be accessed through wells, springs, and boreholes. Groundwater is particularly vital in arid and semi-arid regions where surface water sources, such as rivers and lakes, may be limited or seasonal. Managing groundwater resources sustainably is essential, as over-extraction can lead to issues like aquifer depletion, land subsidence, and contamination.

The Benefits of Groundwater:

• Reliable Water Supply: Groundwater provides a consistent and dependable source of water, especially during periods of drought when surface water sources such as rivers and lakes may dry up. It acts as a natural reservoir, storing water that can be accessed year-round.
• High Water Quality: Groundwater is often of higher quality than surface water because it is naturally filtered as it moves through soil and rock layers, which can remove impurities and contaminants. This makes groundwater a safer source for drinking in many regions.
• Agricultural Irrigation: A significant portion of groundwater is used for irrigation in agriculture. It is essential for maintaining food security, especially in regions with insufficient rainfall or unreliable surface water supplies.

Effects of Concrete Roads on Groundwater
Concrete roads have an adverse effect on groundwater levels in these precarious times of water scarcity. The following are the effects that concrete roads have on groundwater levels:

• Reduced Rainwater Infiltration: Concrete roads are impermeable surfaces that block rainwater from infiltrating into the soil. This leads to a significant reduction in groundwater recharge, as water that would normally seep into the ground is diverted to storm drains, rivers, or lakes instead. Over time, this can contribute to the depletion of local aquifers.
• Increased Surface Runoff: The impervious nature of concrete roads increases surface runoff during rain, which can result in flooding, soil erosion, and the rapid removal of potential groundwater recharge. Instead of being absorbed by the ground, the water quickly flows away, carrying contaminants and reducing the amount of water that reaches underground aquifers.
• Altered Water Table Levels: The disruption of natural water flow patterns caused by concrete roads can affect the water table in the surrounding areas. In some cases, water tables may drop, making it more difficult for wells to access groundwater. In extreme cases, a declining water table can lead to the drying up of wetlands, springs, and rivers that are dependent on groundwater.
• Urban Heat Island Effect: Concrete roads contribute to the urban heat island effect, where urban areas become significantly warmer than their rural surroundings due to heat absorption by concrete surfaces. This can increase evaporation rates and further limit the availability of groundwater recharge, especially in already arid regions.
• Pollutant Contamination: Concrete roads can also lead to the contamination of groundwater due to pollutants like oil, heavy metals, and chemicals from vehicles and road construction materials. As surface runoff flows over roads and into storm drains, these contaminants can seep into groundwater sources through cracks in drainage systems or poorly maintained infrastructure.
• Disruption of Natural Hydrological Cycles: Concrete roads disrupt the natural hydrological cycle by altering the flow and distribution of water across landscapes. This may result in an imbalance in the local ecosystem, negatively affecting both groundwater availability and quality in the long term.

Measures to be Taken to Prevent These Climate Disruptions

• Promote Permeable Pavements: Advocate for the use of permeable materials, such as porous asphalt, permeable concrete, or gravel, which allow rainwater to seep through and recharge groundwater instead of running off. These materials can be used in roads, parking lots, sidewalks, and driveways.
• Support Green Infrastructure: Encourage the implementation of green infrastructure, such as rain gardens, green roofs, bioswales, and constructed wetlands. These systems help manage stormwater naturally by allowing water to infiltrate into the ground and filter pollutants.
• Implement Rainwater Harvesting: Promote or implement rainwater harvesting systems in urban areas. These systems capture and store rainwater from rooftops, reducing surface runoff and giving residents an alternative source of water for non-potable uses.
• Advocate for Urban Planning with Water Management: Work with local governments or urban planners to incorporate sustainable water management practices into city planning. This includes designing cities with more green spaces, permeable surfaces, and efficient drainage systems.
• Raise Awareness: Educate others about the importance of groundwater recharge and the negative impacts of impervious surfaces like concrete roads. Community engagement can lead to more environmentally friendly decisions in urban development.
• Push for Policy Changes: Lobby for changes in policy and building codes that promote sustainable urban development and water conservation practices. Governments can offer incentives or mandates to use permeable materials or create more green spaces.

Long-Term Environmental and Social Benefits of Sustainable Water Management
Incorporating sustainable water management practices, such as permeable pavements, green infrastructure, and rainwater harvesting, offers not only immediate benefits for groundwater recharge but also long-term environmental and social advantages. By allowing water to naturally infiltrate into the soil, these solutions help maintain the health of local ecosystems, which depend on consistent water supplies. For example, wetlands and urban green spaces can thrive, supporting biodiversity and providing essential ecosystem services such as carbon sequestration, habitat creation, and natural flood control (Gill et al., 2007). These benefits extend to urban residents, as green infrastructure helps reduce the urban heat island effect, making cities cooler and more comfortable places to live.

Moreover, sustainable water management reduces the risk of urban flooding, as permeable surfaces and stormwater retention systems absorb and store rainwater, mitigating the overflow into drainage systems (Fletcher et al., 2015). This contributes to climate resilience by protecting communities from the adverse impacts of extreme weather events, which are expected to increase due to climate change. Implementing these strategies creates a ripple effect of positive outcomes, including improved air quality, reduced energy consumption for cooling, and enhanced public health.

Conclusion
Sustainable water management practices, such as permeable pavements and green infrastructure, offer critical long-term benefits beyond groundwater recharge. These solutions not only enhance the resilience of urban environments to flooding and climate change but also support ecosystem health, improve air quality, and foster social well-being. By integrating these practices into urban planning, cities can build greener, more resilient communities that safeguard both their water resources and quality of life for future generations.


References
Hutchinson, B. (2024, April 25). 7 Solutions to ocean plastic pollution. Oceanic Society. https://www.oceanicsociety.org/resources/7-ways-to-reduce-ocean-plastic-pollution-today/

Bouwer, H. (2002). Artificial recharge of groundwater: hydrogeology and engineering. Hydrogeology Journal, 10(1), 121–142. https://doi.org/10.1007/s10040-001-0182-4

Bouwer, H. (2002). Artificial recharge of groundwater: hydrogeology and engineering. Hydrogeology Journal, 10(1), 121–142. https://doi.org/10.1007/s10040-001-0182-4

Li, F., Li, E., Samat, A., Zhang, L., Liu, W., & Hu, J. (2020). Estimation of large-scale impervious surface percentage by fusion of multi-source time series remote sensing data. National Remote Sensing Bulletin, 24(10), 1243–1254. https://doi.org/10.11834/jrs.20209450

Brattebo, B. O., & Booth, D. B. (2003). Long-term stormwater quantity and quality performance of permeable pavement systems. Water Research, 37(18), 4369–4376. https://doi.org/10.1016/s0043-1354(03)00410-x

Scholz, M., & Grabowiecki, P. (2007). Review of permeable pavement systems. Building and Environment, 42(11), 3830–3836. https://doi.org/10.1016/j.buildenv.2006.11.016

Peterson, A., Mcalpine, C. A., Ward, D., & Rayner, S. (2007). New regionalism and nature conservation: Lessons from South East Queensland, Australia. Landscape and Urban Planning, 82(3), 132–144. https://doi.org/10.1016/j.landurbplan.2007.02.003