been effectively used by the city of Kolkata which depends upon the East Kolkata
Wetlands to treat nearly 65% of its wastewater, saving nearly Rs. 4600 million
annually in terms of avoided treatment cost (WISA 2020). Wetlands act as major
flood defence systems for cities such as Srinagar (Jammu and Kashmir) and
Guwahati (Assam) (Kumar et al. 2017). In the hard rock Deccan Plains and arid
regions of the country, there has been an age-old tradition of constructing tanks to
store rainwater for use in irrigation and domestic water supply (Bhattacharya 2015).
The value of coastal wetlands as a buffer against tropical storms has been brought
out by several researchers (Das and Vincent 2009; Kathiresan 2010). Wetlands are
also intricately interwoven with the rich cultural and religious tapestry of the
country, and several wetlands are considered sacred (Singh 2013).
India’s total annual utilizable water resources have been assessed to be
1123 km
3 , of which 39% is accounted for by groundwater (MoWR 2010). The
surface storage capacity of inland wetlands (projected from the wetland extent data
from National Wetlands Atlas and assuming an average depth of 1 m) comes
roughly to 60 km
3 . The contribution of inland wetlands to groundwater recharge
[estimated by the authors using National Wetlands Atlas data and recharge factors
of Central Ground Water Board] comes to 51 km
3 , of which 21 km
3 is from natural
inland wetlands. While the contribution of wetlands to available water resources
may appear small (for want of a more systematic assessment), their value lies in
their availability as a diffuse resource in virtually all landscapes. Unlike large water
storage structures, these systems do not require massive investments into infrastructure for accessing and distributing water, rather can be accessed with very
nominal technology. The ability to support diverse life forms while also playing a
crucial role in food and climate security makes them an incredible water resource.
Notwithstanding the high value of ecosystem services wetlands provide to
society, they continue to be degraded, polluted, encroached upon and converted for
alternate uses. A wetland area trend index constructed by the authors for Indian
wetlands based on 237 published data points for 1980–2014 using wetland extent
trends index method (Dixon et al. 2016) indicates an average decline in natural
wetlands area by 41% and a near commensurate increase in area under human-made
wetlands by 44% (Fig. 2). These trends are similar to those reported globally,
wherein the natural wetlands have been on a decline, and the human-made wetlands
are increasing (Gardner and Finlayson 2018). Such trends are worrying because
natural wetlands are difficult to restore, and their functions cannot be totally
replaced by human-made ones (Gardner and Finlayson 2018).
There is a considerable body of research that highlights the increasing vulnerability of landscapes, wherein natural wetlands have been degraded or lost (Dewan
and Yamaguchi 2008; Acreman and Holden 2013; Marois and Mitsch 2015). This
is especially true for major urban areas in India, wherein large swathes of wetlands
have been converted to give way for housing and other infrastructure needs (Kumar
and Kaul 2018). As a matter of fact, a positive relationship between an increase in
the built-up area, increasing run-off, loss of wetlands and enhanced flood vulnerability has been observed for several cities, such as Mumbai (Zope et al. 2016),
Bangalore (Ramachandra et al. 2019) and Chennai (Gupta and Nair 2011).
Wetlands and Water Management: Finding a Common Ground
109
Wetlands to treat nearly 65% of its wastewater, saving nearly Rs. 4600 million
annually in terms of avoided treatment cost (WISA 2020). Wetlands act as major
flood defence systems for cities such as Srinagar (Jammu and Kashmir) and
Guwahati (Assam) (Kumar et al. 2017). In the hard rock Deccan Plains and arid
regions of the country, there has been an age-old tradition of constructing tanks to
store rainwater for use in irrigation and domestic water supply (Bhattacharya 2015).
The value of coastal wetlands as a buffer against tropical storms has been brought
out by several researchers (Das and Vincent 2009; Kathiresan 2010). Wetlands are
also intricately interwoven with the rich cultural and religious tapestry of the
country, and several wetlands are considered sacred (Singh 2013).
India’s total annual utilizable water resources have been assessed to be
1123 km
3 , of which 39% is accounted for by groundwater (MoWR 2010). The
surface storage capacity of inland wetlands (projected from the wetland extent data
from National Wetlands Atlas and assuming an average depth of 1 m) comes
roughly to 60 km
3 . The contribution of inland wetlands to groundwater recharge
[estimated by the authors using National Wetlands Atlas data and recharge factors
of Central Ground Water Board] comes to 51 km
3 , of which 21 km
3 is from natural
inland wetlands. While the contribution of wetlands to available water resources
may appear small (for want of a more systematic assessment), their value lies in
their availability as a diffuse resource in virtually all landscapes. Unlike large water
storage structures, these systems do not require massive investments into infrastructure for accessing and distributing water, rather can be accessed with very
nominal technology. The ability to support diverse life forms while also playing a
crucial role in food and climate security makes them an incredible water resource.
Notwithstanding the high value of ecosystem services wetlands provide to
society, they continue to be degraded, polluted, encroached upon and converted for
alternate uses. A wetland area trend index constructed by the authors for Indian
wetlands based on 237 published data points for 1980–2014 using wetland extent
trends index method (Dixon et al. 2016) indicates an average decline in natural
wetlands area by 41% and a near commensurate increase in area under human-made
wetlands by 44% (Fig. 2). These trends are similar to those reported globally,
wherein the natural wetlands have been on a decline, and the human-made wetlands
are increasing (Gardner and Finlayson 2018). Such trends are worrying because
natural wetlands are difficult to restore, and their functions cannot be totally
replaced by human-made ones (Gardner and Finlayson 2018).
There is a considerable body of research that highlights the increasing vulnerability of landscapes, wherein natural wetlands have been degraded or lost (Dewan
and Yamaguchi 2008; Acreman and Holden 2013; Marois and Mitsch 2015). This
is especially true for major urban areas in India, wherein large swathes of wetlands
have been converted to give way for housing and other infrastructure needs (Kumar
and Kaul 2018). As a matter of fact, a positive relationship between an increase in
the built-up area, increasing run-off, loss of wetlands and enhanced flood vulnerability has been observed for several cities, such as Mumbai (Zope et al. 2016),
Bangalore (Ramachandra et al. 2019) and Chennai (Gupta and Nair 2011).
Wetlands and Water Management: Finding a Common Ground
109