Evading flood & rethinking urbanization : Urgent need for sustainable planning

Yenning *

Khwairamband Keithel area : Incessant rain floods Manipur on May 30 2024 :: Pix - Khaba Kh

On 31st May 2024, Yumnam Rupachandra, Editor Impact TV posted on Facebook, “Could the flood impact on Thangal Bazar, BT Road & Paona Bazar have been reduced had the width of the Naga River not been reduced and covered?”

This question begs a severe thought – what if the same conservation model is applied to all streams running through the Imphal Valley in the name of containing breaches? That would be disastrous. We’re witnessing the futility of unplanned urbanisation at the cost of lives and properties.

An architect with a master’s degree in urban planning had questioned urban practices in Manipur decades ago. His question, posed some thirty years back, continues to resonate today. It highlights a short-sighted approach to urban development, prioritising individual gain over long-term sustainability. The architect pointed out a concerning trend. Property owners could raise their plots to any desired level by borrowing or even stealing earth from nearby hillocks.

He observed that this practice isn’t merely a cosmetic alteration. Instead, it sets off a domino effect, resulting in perverse competition. As one plot elevates, envious or affected neighbours scramble to do the same. Each person vie to have the highest plinth level – the base upon which their building rests.

This pursuit of an elevated position is often driven by the mistaken belief that a higher plinth offers superior protection from floods. It is an infectious urban syndrome prevailing even today. The architect’s concern went far beyond aesthetics. He recognised the inherent flaw in this approach because it does not address the root cause of the problem - an inadequate drainage system.

Property owners might have felt a temporary sense of security from flooding by raising individual plots. Still, they were playing a game of musical chairs with water. Consider an analogy: a group living on a sloping field during monsoon season. If each person builds a tall platform to escape the rising water, the overall drainage of the field is impeded. The water rises higher, eventually submerging even the platforms.

This is precisely the scenario that unfolds when individual plots are elevated without a comprehensive drainage plan. The consequences of this approach are far-reaching. Unregulated construction practices not only exacerbate flooding but also inflict ecological damage.

Yumnam Rupachandra’s insightful question, echoing across the decades, compels us to delve deeper into Manipur’s struggle with recurrent flooding. We must turn back the clock, not just 30 years, but several decades and re-examine our response to the overflowing streams that have plagued the valley.

Unfortunately, the prevailing approach at the time was characterised by a short-term, reactive mindset. The focus was on restricting the width of the overflowing streams, aiming to “control” the water through brute force. This manifested in constructing embankments with increasing heights – essentially acting as levees built along the riverbanks. However, this very strategy proved to be a double-edged sword.

These embankments encroached upon the natural floodplains. Floodplains are vital low-lying areas that act as a buffer zone, absorbing excess water during heavy rains. By constricting the rivers with embankments, we effectively reduced their capacity to carry floodwater. This trapped the water within the channel, intensifying the flooding in surrounding areas.

Moreover, the quality of construction could have been improved. In haste to “fix” the problem, additional embankments were built on top of the already heightened embankments. The small additional embankments needed to be built with the meticulous engineering required for proper flood control structures. Imagine them more as hastily piled mounds of earth, dwarfed by the immensity of the potential floodwaters.

Unlike robust levees, constructed with layers of reinforced materials and meticulously designed slopes, these “embankments” lacked the structural integrity to withstand the relentless assault of a raging river.

Constructed directly on existing ground, their foundations were often suspect. This shaky base and the rush-job mentality that led to shoddy craft made them particularly vulnerable. Loosely packed earth, lacking proper compaction, became prime real estate for erosion under the relentless current. The materials used often lacked the necessary strength to resist the immense hydrostatic pressure exerted by floodwater.

The absence of crucial elements like drainage channels within the embankments further compromised their stability. Over and above, these “add-on” embankments are easily dwarfed by potential flood peaks, rendering them utterly useless. Imagine a child’s sandcastle facing the ocean tide. It’s destined to crumble under the real deal.

Another point to consider is the unintended consequence of these poorly constructed structures becoming homes for various burrowing animals, including rats. These burrows could act as weak points, creating pathways for water to seep through and ultimately contributing to embankment breaches.

Minister Yaima is correct in this context. In essence, these embankments were a recipe for disaster. They offered a false sense of security while increasing the risk of flooding through their inherent weaknesses.

In a misguided attempt to further fortify against floods, the strategy shifted from rudimentary earthen embankments to seemingly more permanent solutions. It includes masonry walls and retaining walls. While these structures may have offered a perceived sense of sturdiness, they ultimately perpetuated the core issue – the restriction of the natural river course.

These more imposing walls created a false sense of control, allowing settlements and development to creep ever closer to the rivers, further encroaching upon the crucial floodplains. This encroachment had devastating consequences.

Floodplains act as natural buffers, absorbing excess water during heavy rains. By constricting the rivers with permanent walls, the capacity to carry floodwater has been significantly reduced. These structures trap water within the channel, intensifying flooding in surrounding areas.

The hardened surfaces of these walls offer little resistance to water flow, unlike the natural vegetation that once lined the riverbanks. This resulted in faster-moving floodwaters, causing more erosive damage and making them even more dangerous.

Moreover, the construction of these walls entails the destruction of riparian ecosystems. These ecosystems are the delicate zones where land and water meet. Disruption to the natural habitat had a cascading effect on the local flora and fauna.

The allure of these permanent structures has proved to be a mirage. While offering a fleeting sense of security, they exacerbated the flooding problem. They disrupted the delicate balance of the river ecosystem.

The impact of large-scale deforestation, particularly for poppy plantations, adds another layer of complexity to Manipur’s flooding woes. Poppy cultivation thrives on clear land, necessitating the complete removal of vegetation.

The consequences are alarming. The first is increased erosion. Forests act as natural sponges, absorbing rainwater and slowing its descent into rivers. Without this vital layer of protection, the now-bare soil becomes highly susceptible to erosion. Heavy rains wash away the loosened topsoil, increasing river sediment load. This reduces the river’s capacity to carry water and elevates the riverbed, constricting the natural flow during floods.

The second consequence is a faster flow rate. Stripped of vegetation, the land offers minimal resistance to rainwater runoff. This results in water reaching the rivers much faster, creating flash floods that are more intense and destructive.

Imagine a heavy downpour hitting a paved parking lot versus a grassy field. The water on the pavement rushes off quickly. At the same time, the grass absorbs some and allows it to seep into the ground more gradually. The deforested hillsides act like paved surfaces, rapidly channelling water into the already-burdened rivers.

Adding insult to injury, using fertilisers and other chemicals in poppy cultivation further weakens the soil structure. These chemicals can break down the natural binding agents in the soil, making it even more susceptible to erosion. It creates a vicious cycle. Deforestation leads to erosion, requiring more chemicals to maintain soil fertility, further weakening the soil.

The combined effects of deforestation for poppy plantations – increased erosion, faster flow rates, and weakened soil – create a perfect storm for more frequent and severe flooding. The already strained river channels become overburdened with sediment and rainwater, leading to overflows and inundation of surrounding areas. It not only damages property and infrastructure but also disrupts livelihoods and ecosystems.

Yumnam Rupachandra’s question, then, becomes a stark reminder. We cannot continue down this path of reactive, band-aid solutions. We need to embrace a holistic approach to flood management that respects the natural order and prioritises long-term sustainability.

The architect’s question also serves as a wake-up call. It urges us to move beyond short-sighted solutions and embrace a holistic approach to urban planning. The focus should shift from immoral individual plot elevation to creating a well-designed drainage system to manage rainwater effectively.

Matters being discussed, we cannot leave aside the devastating effect of lam-khoppa (encroachment), particularly Khas-land (property vested in Government ownership), including Khongbans (traditional drainage) and pats (wet-land). True, the government does not keep a record of the Khongbans. The onus of preserving these vital drainages is with every leikai.

Some, including bureaucrats and citizens, perceive Khas-land exists for encroachment and later legalisation of private ownership. The Manipur Government has historically struggled to address encroachment. Evictions have often been most successful during periods of President’s Rule. However, there are positive signs. The current government’s efforts to revitalise wetlands, particularly Lamphelpat, are commendable.

This initiative will significantly reduce flooding in Imphal. Here, cooperation from every leikai to keep away neo-rich land grabbers and land sharks is pertinent. We’re talking about our moral compass.

Unplanned urbanisation and lack of regulation have significantly worsened flooding in Imphal. A holistic approach with strict rules and effective implementation is crucial. Considering the valley’s topography and unique drainage patterns, a comprehensive urbanisation plan for the entire Imphal Valley and surrounding foothills is essential.

Settlement along riverbanks and encroachment into floodplains pose the biggest challenge. To mitigate this, planned townships should be developed to draw the population away from vulnerable areas, reducing flooding risk and creating a safer, more sustainable urban environment.