Environment
The Prakasam Barrage at Vijayawada serves irrigation in Andhra Pradesh, but downstream the Krishna River lies dry for most of the year. This post looks at the harm to ecology, climate, wildlife and farming, and proposes a simple fix: a chain of low check dams every 2 to 5 km.
The Prakasam Barrage, located in Vijayawada, is an important structure contributing to irrigation and infrastructure in Andhra Pradesh. However, while the barrage has served these purposes, it has also caused significant ecological and environmental problems for the Krishna River downstream, from Vijayawada to Hamsaladeevi, where the river meets the Bay of Bengal.
This blog explores the ill effects of the barrage and offers a practical solution, building check dams on the Krishna River, which would ensure both ecological restoration and sustainable water management.
Ecological degradation of the Krishna River
The Prakasam Barrage has led to severe environmental damage along the roughly 100-kilometre stretch of the Krishna River downstream, from Vijayawada to the sea. The barrage has altered the natural flow of the river, leaving large parts of the riverbed dry for most of the year. This has resulted in the degradation of the local ecology, with the once-thriving riverbank now barren and devoid of life. The loss of natural water flow has disrupted the river’s ecosystem, leading to the destruction of soil fertility and the loss of plant life along the banks.
Rising temperatures and climate change effects
The dry riverbed passing through Vijayawada has also contributed to rising temperatures in the region. Without the cooling effect of flowing water, the city and its surrounding areas have experienced extreme heat during summer months. This has forced residents to rely heavily on air conditioning, which increases energy consumption, further contributing to air pollution and worsening the region’s heat problems.
The absence of a consistent water flow has had a profound impact on the local climate, creating a vicious cycle of environmental degradation and climate-related issues that continue to worsen over time.
Loss of wildlife and aquatic species
The lack of water in the Krishna River downstream of the Prakasam Barrage has severely affected local wildlife. Birds, animals and aquatic species that once thrived along the river now struggle to survive without a consistent water supply. The dry riverbed has left many species without their natural habitat, leading to migration, reduced populations and, in some cases, their disappearance from this stretch of the river. This has resulted in a dramatic decline in biodiversity, which has long-term consequences for the ecological balance of the region.
Agricultural decline and economic loss
The reduction of water flow downstream has also led to a decline in agricultural productivity. Farmers who depend on the Krishna River for irrigation are now facing water shortages, leading to lower crop yields and significant economic losses. The once fertile lands along the river are turning barren, putting the livelihoods of thousands of farmers at risk and impacting the regional economy.
The solution: check dams for sustainable water management
To address these pressing issues, a viable and sustainable solution is to construct check dams along the Krishna River at regular intervals of 2 to 5 kilometres. These check dams, designed to store water up to 3 feet in height, would retain rainwater and allow it to accumulate throughout the year. By creating a series of reservoirs along the river, this solution would help in maintaining a continuous flow of water, even during dry months.
The same approach has already worked on smaller rivers: in Rajasthan, two check dams in Dholpur created a 6.5 km reservoir and brought migrant families back to farm.
Benefits of constructing check dams on the Krishna River
Water retention: The check dams would retain water in the riverbed, ensuring that water remains available throughout the year. This would help restore the natural ecosystem, allowing the region’s flora and fauna to thrive once again.
Temperature regulation: By ensuring that the river holds water year-round, the check dams would help cool the surrounding environment, reducing the extreme heat that currently affects the region. This would decrease reliance on air conditioning, lowering energy consumption and reducing air pollution.
Biodiversity restoration: With consistent water availability, birds, animals and aquatic species would have access to water and habitat, leading to the revival of biodiversity along the river. The return of natural habitats would restore ecological balance and improve the region’s overall health.
Improved agriculture: Farmers would benefit from a reliable water source, allowing for consistent irrigation and improved crop yields. This would not only help the region’s agricultural economy recover but also contribute to food security and the livelihood of local farmers.
Groundwater recharge: Check dams would also help recharge groundwater by allowing water to percolate into the ground, providing a sustainable source of water for local communities and agriculture. Kalyaan’s guide to rainwater harvesting in large open spaces explains more ways to recharge groundwater.
Conclusion: a call for action to build check dams
The Prakasam Barrage, while beneficial in some aspects, has caused significant environmental damage that requires immediate attention. Constructing check dams along the Krishna River is a practical and sustainable solution to restore the river’s ecological balance, support local biodiversity and improve agricultural productivity.
By taking action to implement these measures, the Government of Andhra Pradesh and other concerned authorities can ensure the long-term health and prosperity of the region. This solution would not only address the current challenges but also protect the environment for future generations. Kalyaan has proposed the same idea for the Jawai River in Jalore, Rajasthan.
It is crucial that we act now to restore the Krishna River and preserve it as a vital natural resource for both people and wildlife. Let’s work together to implement sustainable water management solutions and create a more balanced, healthier ecosystem for all.
Questions and answers
Why is the Krishna River dry below Prakasam Barrage?
The barrage holds back and diverts the river's flow at Vijayawada, so for most of the year very little water flows on to the roughly 100 km stretch downstream to the sea.
How would check dams on the Krishna River help?
Low check dams every 2 to 5 km would hold rainwater and river flow in a chain of shallow reservoirs, keeping water in the riverbed all year for farms, wildlife and groundwater.
How high would the check dams be?
The proposal is for low structures that store water about 3 feet (roughly 1 metre) deep, enough to keep the river alive without flooding the banks.
Who can build these check dams?
The Government of Andhra Pradesh and the concerned water authorities, ideally with local communities, as Dholpur's villages did with their own check dams.
