TOI : Coastline sees sea change: Fish stock up, sewage dilution better : Sept 11, 2007
Coastline sees sea change: Fish stock up, sewage dilution better
TIMES NEWS NETWORK
There’s some good news on the water front. After long years of neglect,
Mumbai’s coastline is finally beginning to experience the benefits of an
ambitious clean-up which involved treating sewage and discharging it far out
into the sea.
The Environment Status Report released by the BMC quotes the findings of
a recent survey carried out by the National Environmental Engineering
Research Institute (NEERI) to show that in the past few years, the quality
of seawater around Mumbai has improved considerably.
The study was carried out to determine “the existing water quality
status of sea beaches, sea fronts and along west coast at 1 km, 3 km and 5
km line from the shore starting from Colaba to Madh,” says the report. The
results show that “water quality at 1 km line from the shore is moderately
improved,” it says.
The findings have been linked to the implementation of the Mumbai Sewage
Disposal Project (MSDP)-Phase I, which was funded by World Bank.
MSDP-Phase I included construction and laying of 3.5-km-long pipes to
dispose the sewage far out into the sea and also construction of artificial
lagoons to aerate the waste and increase oxygen content before discharging
it.
At Colaba, Worli and Bandra where sewage is now being treated and then
discharged into the sea through the marine outfalls or long pipelines, the
water within a kilometre of the shore meets environmental requirements. The
reason for this is that the waste is now being dispersed over a much larger
area resulting in its dilution, thereby mitigating the adverse impact on
marine life.
Rakesh Kumar, NEERI’s zonal head in Mumbai, acknowledged as much. “There
was a time when waste water was spoiling the beaches and waterfront. Now
with the outfalls, there is dispersion of sewage water far away from land.
It is still not an ideal situation, but once BMC introduces better treatment
for waste water, the situation will improve further,” he said.
According to the report, better coastal water quality has even led to
improved yields for the indigenous fishing community.
“Fishermen have expressed satisfaction over greater quantity and variety
of fish catch,” says the report, adding that the benefits have been linked
to the removal of “domestic sewage and industrial waste from the inner city’s
natural water courses, surface water drains, shore line and beaches.”
To sustain the momentum of this environment-friendly measure, BMC has
now begun work on MSDP Phase-II, estimated to cost Rs 5,000 crore. The
objective is to bring the entire city within the sewerage network. MSDP-II
is scheduled to be ready in 2025 when the projected population of 16 million
is expected to generate 3,400 million litres of sewage daily.
On the Waterfront
Area | Projected sewage flow in 2025
Colaba | 31 MLD Love Grove | 399 MLD Bandra | 241 MLD Dharavi | 337 MLD
Versova | 278 MLD Malad | 644 MLD Gorai | 39 MLD Bhandup | 253 MLD Ghatkopar
| 400 MLD Total | 2,622 MLD
(MLD = million litres daily)
PLANS FOR PHASE-II OF SEWAGE TREATMENT
Primary treatment plants will be constructed at Colaba, Worli and Bandra
Sewage-handling capacity of lagoons at Versova, Malad, Bhandup, Ghatkopar
will be enhanced A new marine outfall at Erangal, 3.4 km long and 3.5m in
diameter. Versova and Malad will have effluent pumping stations 14 existing
pumping stations will be expanded, replaced or refurbished 1 new pumping
station will be constructed 15 km of sewer lines will be expanded 25 km of
man-entry sewer lines will be rehabilitated Projects to be completed by 2012
and will cost Rs 1,896 crore