Ensuring freshness of water for one and all – Conserving coastal wetlands for water security

Home » Blogs » Healthy Wetland Nature » Integrated management planning » Ensuring freshness of water for one and all – Conserving coastal wetlands for water security
Blog

Water security is central to lives and livelihoods of people.  As we endeavor to achieve the SDGs, the overall water environment is increasingly getting stressed. Population growth has resulted in an exponential increase in the demand for water. The way in which water is managed has far reaching human and economic implications and is key to the economic success of the countries and will certainly determine the success of the SDGs.

India has an estimated utilizable water resources of 1123 km³. 61% of utilizable water is available as surface water resources and the rest as groundwater. The per capita water availability in the country has declined from a high of 5,277 m³ in 1955 to 1,820 m³ in 2001, and is likely to slip below 1,000 m³ by 2025, affecting over 600 million people. 54% of the total area in India is facing ‘high’ to ‘extremely high’ stress on its water resources due to the fall in groundwater levels and deterioration of surface water sources. As climate change makes rainfall more erratic and less predictable and as groundwater situation becomes perilous year after year, there is an urgent need to look in to holistic solutions to address water security concerns of communities and to address ecological sustainability of ecosystems.

Water security at any level from household to the global, means that every person has access to enough safe water at affordable cost to lead a clean, healthy, and productive life, while ensuring that the natural environment is protected and enhanced. Water security is determined by the quantum and distribution of the three forms of water viz. blue, green and grey in a system. A system may receive sufficient green water from rainfall but it may not be having the required surface infrastructure to capture the stormwater runoff and convert it to blue water.

Through their capacity to store water, recharge groundwater and buffer extreme events, wetlands form a critical part of water natural infrastructure.

Healthy and functioning wetland ecosystems play an important role in storing water and regulating quantity as well as quality of water. Many floodplain and riverine wetlands are known to have this hydrologic capability. This important attribute of wetlands has been used by town and water planners since centuries for supplying water to communities living around them. This is particularly true in landscapes where freshwater is a scarce commodity. There are numerous examples of such natural and man-made wetlands in India that play a crucial role in bridging the gap between demand and supply of water. The Sasthamkotta lake in Kerala state caters to the water supply needs of over 3.5 million residents of Kollam city. Similarly, in arid landscapes of Rajasthan, lake Pichola and Fateh Sagar were constructed to meet the drinking water and irrigation needs of the Udaipur town and down south in the Deccan plateau region, Nizamsagar and Osmansagar lakes supply water to the Hyderabad city.

The importance of wetlands in coastal areas for water security is immense as they serve to enhance the freshwater conditions of coastal aquifers.

Planning water supply projects in coastal areas is challenging, complicated by factors of complex geology, hydrology, hydrogeology and heterogeneous sedimentation resulting from dynamic marine and fluvial processes. Development of groundwater in these areas is constrained by salinity hazards.

The coastal tracts of Odisha is shaped up by high rainfall conditions, freshwater fluvial regimes and seawater influences and presents typical problems in ground water development and management for drinking, irrigation and other use. The coastal region receives plentiful of annual rainfall, averaging 1480 mm, from the south west monsoons as well as the north east monsoons.  Mahanadi, and five other major rivers including the Rushikulya drain the region bringing in heavy riverine flows. The sediments that the rivers bring in create extensive deltas. The rates of sand accretion along the shores in Odisha, are said to be amongst the highest in the world. So high are the transportation rates that Konark Sun Temple, built originally on the seashore in the 13th century, is now more than three km away from the coast.

As the rivers near the coast such high rates of deposition divides the rivers into a number of distributaries.  High rainfall, diminishing speeds of river flows, upon interaction with sea water creates conditions that are conducive for formation of shallow aquifers. Studies indicate that the ground water in shallow aquifers of coastal Orissa, within a depth of 60 to 80 m, is suitable for drinking and irrigation. These coastal aquifers extend from Chilika Lake in the south to Subarnarekha River in the north.

The wetlands here are important not only for their groundwater recharge function but to maintain the required hydrostatic pressure to sustain the thin wedge of freshwater above the sea water.  Any ill planned development here may offset the delicate surface – groundwater equilibrium, increase salinity risk in groundwater and impact lives of communities living around.

The case highlighted here is of a coastal lake, Tampara situated in Ganjam District, south of the Rushikulya River in Odisha state. The lake spanning around 325 ha offers an extensive impoundment of rainwater sustained by natural elevations along the east and west margins of the lake.  This important attribute of the lake as a natural water harvesting and groundwater recharge structure, underpins its importance as a drinking water source for a population of around one lakh people living in the town of Chhatrapur, situated in the lake catchment.

Tampara Lake, Odisha

 

The lake catchments spread over precambrian crystalline rock formations and quarternary sediments at places.  The sub-surface geology around Chhatrapur town has revealed the presence of hard rock Khondalite formations. These hard rock types devoid of primary porosity that could store groundwater, have low yield and offer little prospect for any large scale groundwater abstraction.

Preliminary observations to understand surface groundwater relationships made as part of Watershed – India programme, suggests that while hard rock geology around Chhatrapur may be the restraining factor for groundwater development, Tampara Lake and its downstream coastal reaches have a sub-surface repository of groundwater that are helping to meet the water supply needs of both urban and rural populations.

Aquifers along the Tampara are tapped by a water supply project that was started in 1972. The project that began with two to three pumps extracting water directly from the lake, from one single tank equivalent to 0.15 million litres, now has 17 borewells that tap in the aquifers along the lake, with an installed capacity of supplying around 0.7 million litres of water.

The rural water supply systems in ten villages around the lake, barring a couple of villages where household piped water supply systems are operational, largely comprise of public handpumps. These handpumps installed at shallow depths also tap in to the shallow coastal aquifers.

It is a common knowledge that the complex sea water and freshwater interactions result in distinct vertical and horizontal zonation of freshwater aquifers, particularly in areas with hard bedrock. It can be observed that within the same village, handpumps in one part of the village, mostly the ones closer to the coast have freshwater, whereas the handpumps situated landwards have salinity issues. Similarly, there are instances of borewells not yielding the proper quality and quantity of water leading to failure of water supply schemes in a few villages that are situated upstream of the lake. This fact is supported by studies on coastal aquifers of Odisha which reveal that the depth to basement of the alluvial aquifers here is variable, landwards it is shallow while it deepens seawards. As new schemes for piped water supply that rely on groundwater abstractions are being sanctioned and implemented, it becomes critical that enough attention is paid to adopt a holistic approach to water management in the area.

As we move towards SDG 6, a critical concern is to ensure sustainability of water resources.

Surface water availability here is rapidly shrinking. A temporal analysis of the lake catchments reveals that the capacity of the entire system to store water and recharge the aquifers has undergone a significant decline as marshy areas and wetlands have decreased considerably over the last two decades.

Sanitation coverage in the villages is inadequate and open defecation is a common practice amongst the rural communities. Runoff water from the catchment, as well as wastewater drains flow directly in to the lake. All this has resulted in significant eutrophication of lake and the lake is witnessing a rapid loss of area due to siltation in its southern ends.

There are growing concerns over falling lake levels in Tampara and drying up during summers which is sometimes catastrophically complete, as witnessed during a few years in the 1990s. This not only adversely impacts the drinking water supply from the lake but also puts at risk the livelihoods of other stakeholders living around the lake. As water demands of populations grow, there is a need to adopt an integrated approach to ensure water security.

A multi-stakeholder environment and the pressures on limited resources highlight the need for community led solutions for lake and catchment management so as to enhance water security.

Located in a predominantly rural set up, the lake also supports livelihoods of communities who have traditionally lived in close association with the lake. The association ranges from direct dependencies in the form of fisheries or for irrigation water needs to aesthetic experiences of boating in the lake’s cool and serene surrounds. 170 Tior community fishermen living in fishing hamlets surrounding the lake, use the lake for fishing. Similarly, agriculturists of the villages have benefitted till recent past from minor irrigation projects which enabled them to grow groundnut and other crops.

Wetland conditions around Tampara and its adjoining areas, benefit one more stakeholder – the Kewra flower collectors and Kewra water distilleries.  Kewra or Pandanus odoratissimus L. grows profusely along Tampara and its adjoining coastal stretch thriving in the brackish marshes and watercourses. The flowers of the plant yield the Kewra or Ketaki essential oil that has a pleasant odour and is used in sweets, confectioneries and perfumery. Kewra flower collection happens to be main source of income for people in some of the villages around the lake, particularly those situated near Gopalpur and some of the finest types of Kewra essence in India is said to be produced from this area. During monsoons and other parts of the year, every morning women folk embark on this activity and could be seen carrying a bundle of corn like flowers of the Ketaki over their heads. This is sold to local collectors or directly to the distilleries which fetches them around 1 USD for nine or ten flowers.

While the Kewra plant requires wetland-like conditions and abundant water to grow, its distillation also requires water. It is estimated that there are nearly 200 registered Kewra distillation factories in Ganjam District. Though, the quantum of water used is not huge but the distilleries install motor pumps to source water from nearest ponds, often constructing tanks to store it. Thus, this perfume industry will not thrive if water becomes a scarce commodity.

Kewra processing unit in Matikhala

 

It is widely observed, that while urban settlements benefit from water supply from wetlands, there is hardly any investment made to ensure the sustainability of the source.  This is more so when the source is not situated within the immediate urban limits.  More often than not, there is no or little coordination of the water supply department with the institution that is responsible for the management of the water resource and its catchment. Unabated unwise use of resource continues to the point of significant resource degradation, leading to conflicts of interests, further mismanagement and the ecosystem reaching a state of no return.

There is an urgent need to look in to integrated solutions for water resource management that goes beyond the realm of demand and supply. Often institutional arrangements create artificial divides.

For all practicalities of purpose and in order to ensure source sustainability, water supply programmes need to be in sync with water resources management. In the past, frequent drying of lake necessitated hydrological interventions to reduce outflows to the Rushikulya River from the lake. As recalled by a fisherman, when the Tampara Lake dried up completely in 1997, it necessitated the District Collector’s intervention, following which a pond was constructed for the Tior fishermen in Taraipatpur so that they could meet their water needs and cultivate fish.  However, such curative measures are often not enough and far from being holistic. As water regime degrades tending to become unsustainable with growing population needs, the communities bear the cost of poor resource management practices.

Pivoting on four pillars of ecological sustainability, social equity and economic efficiency, Integrated Water Resource Management (IWRM) process requires looking at water security in a coordinated manner whereby development and management of water resources maximise the social welfare in an equitable manner without compromising the sustainability of vital ecosystems.  Institutionalising IWRM however, involves both centralised approaches as well as localised interventions and requires adequate capacities to implement it at different scales.

Bottoms up participatory approaches that aim at enabling community led and demand centric water solutions has emerged as the way forward, to make this process operational on ground, in which communities identify the opportunities to conserve and manage their water bodies to meet their various needs. This finds resonance in the national programmes as well which call for investing in community based management of water services and ensuring source sustainability. While many aspects of how these community based approaches work on ground, in terms of rights, access, institutions, and sustainability widely vary and are still emerging. One thing that is common in all cases is the need to develop the right kind of capacities within communities to assess, plan, implement and manage their own water needs and resources.

‘Connecting people to nature’ was the theme of the National Environment Day in 2017.  As summarized in the words of a local Self Help Group representative

“As we move towards the sea the water from the handpumps becomes sweeter.”

It is time we recognise and establish this in order to maintain this sweetness of water for one and all.

 

 

Leave a comment