Despite the recognition of the importance, and a slew of programmes and projects focusing on watershed development, the scenario today is typified with a sense of lost focus and minimal effectiveness.
One of the major concerns that is gaining widespread acceptance, at least in the research community (and discussed at length in the TEEB report on wetlands) is that much of water resource development that have been undertaken to increase access to water have not given adequate consideration to harmful trade-offs with other services provided by wetlands, and many such conversions of wetlands have favoured provisioning services (notably food production) at the expense of losing or reducing delivery of regulating and supporting services. Given the often high values, and the diversity of ecosystem services provided by intact wetlands, and that a large proportion of these values are from services such as regulation of water flows, moderation of extreme events and water purification, the widespread and major losses of all types of inland and coastal wetlands have led to a situation where the ecosystem services of wetlands are poorly delivered to people.
Permitting the remaining wetlands to be converted or letting them degrade means further loss of their value to people. Such costs of inaction (or actions to convert wetlands) can be very high. Global research provides much needed evidence of this scenario which citizens of Chennai can well relate to: the loss of one hectare of wetland is estimated to correspond to an average increase in storm damage from specific storms of $33,000. The costs of just one summer flooding event in the UK, in 2007, are estimated at £3.2 billion ($ 5.2 billion), with damage and costs occurring largely in areas of former river floodplain converted through urban, industrial and infrastructure developments.
When wetlands have been allowed to be lost or degraded, there is a second category of the cost of such inaction: the cost of restoration. Overall, whilst costs of restoration can be high, and require long term management investment, the resulting economic benefits to people can outweigh such costs. However, in general even with active restoration interventions, once wetlands have been disturbed, they either recover slowly (over decades or centuries) or move towards alternate states that differ from their original (pre-disturbance) state. Removing the stressors or pressures on the ecological character of existing wetlands is the best practice for preventing further loss and degradation. When this is not feasible or when degradation has already occurred, wetland restoration must be considered as a potential response option. Some wetland restoration efforts have failed due to, among other things, narrow objectives which focus on one benefit or a partial package of benefits. These failures, once accepted could form the bedrock for a more multi-purpose, scientific restoration of wetlands that are case specific. The commitments and obligations under the Ramsar Convention clearly mandate wise use and the avoidance of wetland loss and degradation as the first and highest priority. The Convention has also provided national governments and others with a framework on how to avoid, mitigate and compensate for wetland loss and degradation, which includes identification of the opportunities for wetland restoration.
The recently enacted National Wetland Rules are based on the principles outlined by the Ramsar Convention, and the State Wetland Authority of Tamil Nadu (constituted in 2016) cannot afford inaction.
— The writer is Managing Trustee, Care Earth