Water as Leverage- Setting the scene for a call for action

Water as Leverage for Resilient Cities Asia Setting the Scene for a Call for Action Content
2.2.2 Drainage
Almost 50% of the canals and rivers that
historically shaped Khulna’s drainage system have
disappeared in the last thirty years. This is mostly
due to human intervention; people filled in canals
to create more inhabitable space. Other reasons
include the accumulation of solid waste and natural
sedimentation processes. As a consequence,
the drainage system is not working optimally,
contributing to more frequent and severe floods and
waterlogging. In addition, open and green spaces in
central Khulna are disappearing.
Khulna is very vulnerable to tidal floods,
cyclones, storm surges and waterlogging after
heavy rainfall. Especially the combination
of typhoons and high tide leads to surges
that inundate large parts of the city, affecting
thousands of people.
Legal and illegal real estate developments
on embankments and ponds, as well as
encroachment by agriculture, reduce the
drainage capacity of the city. Whereas the
ponds are traditionally the most important
source of water, the rivers and canals function
as drainage for rainwater and sewerage.
As such, the canals and rivers are generally
of little social importance. Due to natural
sedimentation processes and waste disposal,
big parts of the original canals (khals), forming
the backbone of the drainage system, became
stagnant or disappeared. The Mayur river,
into which most canals flow, faces similar
problems. The river lies lower than the Rupsha
river, is protected by gates for flooding and will
need pumps in the future in order to maintain
its drainage function. Taken together, this lack
of drainage capacity leads to waterlogging
during heavy rains. It takes several days to
drain the logged water, paralyzing daily life,
which in turn results in income loss for people
who rely on occasional work, like street
venders and rickshaw drivers.
A person removing solid waste from one of Khulna’s ponds.
Encroachment for agricultural purposes.
Together with accumulation of solid waste
and sedimentation processes, this has led
to impairments of Khulna’s drainage system,
resulting in more frequent and more severe
floods. In turn, these floods might impede
mobility, as infrastructure becomes unusable or
damaged, and might contribute to the spread
of waterborne diseases such as diarrhea,
dengue, ringworm and dysentery. A lack
of sewerage as well as proper solid waste
management results in the distribution of
large amounts of pollution and waste through
the city during floods. The lack of waste
management itself also increases the drainage
problems. Many drains and drainage canals are
blocked by solid waste.
Khulna has a population of 1.9 million, which
produces about 450 tons of solid waste each
day. Given that the population is growing
rapidly, enhancing the waste management
system is an important challenge for the
future. At this point, about 42% of this waste is
collected and transferred by truck to a landfill
close by Rajbandh, about ten kilometers away
from Khulna. Furthermore, waste management
is currently still handled by too few people
and with inadequate resources (i.e. small
trucks and small garbage bins). The waste
Siltation of a creek.
that remains uncollected tends to end up in
the open spaces throughout the city, thereby
possibly contributing to issues of waterlogging
and contamination of the air and water. A
wide range of NGOs have shown interest in
improving the waste processing system of
Khulna. Recent interests focused on further
improving the community waste management
programs and using the waste collected at the
landfill as a resource (Ahsan & Shams, 2009).
Encroachment
by Agriculture
Landfill
Encroachment and
siltation of a creek.
Encroachment by
housing development
Algae bloom
Tidal Sedimentation
204 KHULNA
Water Issues
PART 2/Background Information on the Partner Cities
205