The disappearing Puducherry seaside comes again to life. A synthetic reef got here to its rescue – Gaonconnection


Puducherry

Proper reverse the Secretariat constructing in Puducherry (traditionally referred to as Pondicherry), a portion of seaside juts out into the ocean. Residents, kids and vacationers get pleasure from strolling on the seaside sand and clicking selfies with the ocean waves. Younger {couples} stroll hand in hand having fun with the cool sea breeze.

However,
simply over a yr in the past, there was no seaside in Puducherry. A stone seawall and a
promenade had been unsuccessfully making an attempt to maintain waves of the Bay of Bengal from
destroying the inland infrastructure. The seaside highway had developed cracks,
threatening to erode into the ocean.

That’s
when the Nationwide Institute of Ocean Expertise (NIOT), a Chennai-based
analysis institute hooked up with the Union ministry of earth sciences, determined
to implement a singular seaside restoration mission in Puducherry. 

“Fairly
than utilizing concrete constructions like groynes and stone seawall, we adopted a
sustainable mission for seaside restoration at Puducherry,” MA Atmanand,
director of NIOT advised Rural Connection. “After analysis and modelling research,
a synthetic reef was submerged into the ocean, which, within the final one yr, has
helped restore part of the seaside. Each native folks and vacationers now use it
for recreation,” he added.

Puducherry had misplaced its seaside, however a pilot mission by the Nationwide Institute of Ocean Expertise, Chennai, has helped restore part of the seaside. Pic: Nidhi Jamwal

Seashores
are usually not simply areas for recreation. Seashores are rivers of sand. They assist
marine life and livelihood of fishers, and likewise maintain a test on groundwater
salinity.

The
Puducherry seaside restoration mission has obtained the assist of the native
residents and environmental organisations.

“Until
the Nineteen Eighties, Pondicherry used to have an exquisite sandy seaside, which
slowly began to vanish after the development of Pondicherry harbour in
1989. Quickly, we misplaced our complete seaside with sea waves threatening to eat into the
infrastructure,” mentioned Probir Banerjee, president of Pondicherry Citizen’s
Motion Community (PondyCAN), a Puducherry-based environmental organisation.
“We spent many years making an attempt to get the federal government to handle coastal erosion, however
to no avail. Lastly, the NIOT applied its mission, which has borne fruits,”
he added. 

A
yr in the past, in January 2019, Harsh Vardhan, the Union minister of earth sciences,
inaugurated the restored
Puducherry seaside lauding the efforts of NIOT.

“The
pilot mission by NIOT has efficiently demonstrated how a seaside could be
restored,” mentioned M Rajeevan, secretary, Union ministry of earth
sciences. “However, we should additionally do not forget that seaside restoration is expensive. The
Puducherry mission costed about Rs 30 crore. Our first precedence needs to be to
keep away from coastal erosion and shield our seashores,” he added.

How a seaside disappeared

Puducherry, 151-km south of Chennai, at all times had an exquisite sandy seaside. Individuals who grew up within the union territory within the Sixties-70s-80s, bear in mind early morning walks and sports activities actions on the seaside. 

Issues
began to vary in 1989, declare native environmentalists.

“That
time the Centre was giving funds to varied state governments to construct harbours
and ports. Harbour development began in Puducherry in 1989,” mentioned Banerjee. “The
harbour stopped the motion of sediment, thus depriving our seaside of its sand
resulting in its disappearance,” he lamented.

This
is famous in a 2011 report of the Nationwide
Centre for Sustainable Coastal Administration below the Union ministry of
setting, forests and local weather change: “… zones of abrasion have elevated,
presumably associated to the development of the Puducherry Port within the late Nineteen Eighties
and different groyne subject constructions alongside this a part of the coast subsequent to
the development of the Puducherry Port.”

Seashores are essential for the livelihood of India’s fishing group. Pic: Nidhi Jamwal

Explaining
the science behind it, J Ram Kumar, a mission scientist with Chennai-based
Nationwide Centre for Coastal Analysis (NCCR), one other institute below Union ministry of earth sciences, mentioned: “Coast is sort of a river of sand with
steady motion of sand as a result of wind and waves. If you assemble a
construction on the coast, you primarily construct a dam to cease the motion of
sand. Locations the place sand can’t attain begin to erode.”

Curiously,
on the east coast of India, the place Puducherry is situated, waves strategy the
coast from the southwest course for about eight to 9 months a yr. This
southwest strategy of waves induces northward transport of sand. If a coastal
construction is constructed, then accretion takes place on the southern facet and
erosion on the northern facet of the construction, defined Kumar. 

For
the remaining three months of the yr, which is in the course of the northeast monsoon
(October to December), the waves strategy from the northeast facet and the sand
strikes in the wrong way. This motion of sand is named longshore
drift or seaside drift.

In accordance
to Banerjee, when the harbour was proposed, the Central Water and Energy
Analysis Station (CWPRS) was conscious of the very fact
that longshore drift shall be affected. Therefore, within the design doc, dredging
of sand — sand bypass system — was part of the mission. As per it, sand had
to be usually dredged from the south of the harbour and pumped to the north
to make sure Puducherry seaside doesn’t disappear. However, the identical was not carried
out and our seaside fully vanished within the subsequent few years, he
complained.  

The
2011 report, too, notes: “…
the sand bypassing system has not been utilised appropriately. Due to this,
deposition occurred on the south facet of the breakwater and erosion on the
north facet of the northern breakwater. For the safety of shoreline erosion,
the Puducherry authorities has constructed riprap utilizing boulders… In lots of locations alongside
this riprap, the seabed under the riprap is eroded as a result of extreme wave motion
and floor subsidence.”

This
report of the
Nationwide Centre for Sustainable Coastal Administration concluded that the “shoreline
of Puducherry has undergone excessive erosion on a long-term foundation… The coast
adjoining to the south breakwater, sediments are trapped on the southern facet of
the breakwater and, because of this, there is no such thing as a web sediment motion in the direction of the north
of the Puducherry Port, inflicting erosion on the northern facet of the north
breakwater

“We
have had seaside erosion for about 30 years in Puducherry, which corresponds with
the development of the harbour. An enormous gap within the coast has been created in
the final three many years that now must be crammed up with sand to revive our
seaside,” mentioned Aurofilio Schiavina, co-founder of PondyCAN.

Coastal erosion all alongside the shoreline

Puducherry isn’t the one coastal space within the nation dealing with erosion. India has a protracted shoreline of over 7,516-km of which 6,100-km is within the mainland.

A
July 2018 joint report, Nationwide Evaluation of
Shoreline Adjustments alongside Indian Coast (1990-2016), by NCCR and
Union ministry of earth sciences has scientifically documented shoreline
adjustments alongside a 6,031 km shoreline utilizing satellite tv for pc photos. The outcomes are
categorized in three classes — erosion, secure and accretion.

The examine discovered that between 1990 and 2016, about 34 per cent of the Indian shoreline is dealing with coastal erosion, 28 per cent has accretion, whereas 38 per cent is secure (see desk: Shorelines adjustments alongside the Indian shoreline 1990-2016). Greater than 40 per cent of the entire erosion has been recorded in 4 coastal states of West Bengal, Puducherry, Kerala and Tamil Nadu.

Desk: Shorelines adjustments alongside the Indian shoreline 1990-2016

Supply: Nationwide Centre for Coastal Analysis, Chennai

Coastal
erosion is each a pure phenomenon and impacted by human actions. Waves,
winds, tides, nearshore currents and storms trigger pure adjustments to the coast.
Anthropogenic actions, akin to the development of harbours and jetties,
dams, seawalls, seaside sand mining, destruction of mangroves, and so forth exacerbate
coastal erosion.

Puducherry seaside restoration mission

As per the July 2018 report, 57 per cent of Puducherry’s shoreline, the second-highest within the nation, is dealing with erosion. To handle coastal erosion, NIOT has applied a pilot mission within the union territory.

In
the unique mission doc, Detailed Design Report on
Pondicherry Seaside Restoration Venture, there are three
parts of the seaside restoration mission: a nearshore wedge reef, south
reef, and seaside nourishment utilizing 450,000 cubic metre of sand (see determine:
Parts of Puducherry seaside restoration mission
).

Up to now, just one element — wedge reef — has been accomplished.

Determine: Parts of Puducherry seaside restoration mission

Supply: Detailed Design Report on Pondicherry Seaside Restoration Venture, NIOT, Chennai, Could 2016.

The
wedge reef is a triangular form metal caisson resting on a mattress of rocks laid
horizontally at 2.5 m depth. It’s 50 metres (m) in width and 60 m in size.
The reef crest is designed to be on the water floor at low tide and submerged
by multiple metre throughout excessive tide.

The
wedge reef element of the Puducherry mission
was began in Could 2017 and resulted in October 2018. Within the final 15 months,
optimistic outcomes are displaying up. A sandy seaside has come up proper reverse the
Secretariat constructing the place reef has been submerged within the sea.

“The
reef tries to change the wave setting domestically via wave transformation.
It tries to vary the wave course, thereby altering the course of the
sediment or sand transport,” defined Kumar. “The reef stops the sediment from
transferring north. However, throughout excessive tide, when it’s submerged one metre under sea
degree, sand can transfer northward, which is fascinating in order that the north doesn’t
change into sand poor,” he added.

Explaining
the advantages of wedge reef, Schiavina mentioned: “The
benefit of reef in comparison with different constructions designed to retain sand is that
the reef retains solely as a lot sand as is required to revive the eroded seaside. It
doesn’t deprive different seashores of their fair proportion of sand. It behaves like a
pace breaker.”

A 2018 examine has discovered about 34 per cent of the Indian shoreline is dealing with coastal erosion. Pic: Nidhi Jamwal

Venture isn’t full but

A wedge reef is only one element of the seaside restoration mission at Puducherry. The complete coastal safety mission at Puducherry entails three parts — wedge reef, south reef, and seaside nourishment element.

The
wedge reef element needed to be applied by the NIOT, which has been achieved.
The remaining two parts are to be applied by the state authorities, however
delayed as a result of a scarcity of funds. All of the three parts mixed are anticipated
to guard the coastal stretch of about 1.5-2 kilometres.

As
per the information report, Lieutenant Governor Kiran Bedi has requested the Union ministry of earth
sciences to “allocate ample funds for extension of the seaside on the southern
facet.” However, the ministry’s position was restricted to the wedge reef element of the
mission and the opposite parts needed to be applied by the Puducherry
authorities.

In the meantime,
the NIOT has applied one other coastal safety mission at Cuddalore
Periyakuppam village situated between Mahabalipuram and Puducherry.

“In
this fishing village, fishers had misplaced their seaside the place they used to fix
fishing nets, convey fish catch and public sale it. We now have put in a geo-tube
based mostly shore safety methodology, which has helped restore the misplaced seaside,” mentioned
Atmanand.

Explaining
the functioning of geo-tube luggage, Kumar mentioned that geo-tube is a bag product of
naturally out there supplies, crammed with sand and positioned within the sea, away
from the shoreline, at Cuddalore Periyakuppam website. The perform of geo-bags is
to scale back the wave vitality coming to the coast by making the waves break
off-shore.

“At
Cuddalore Periyakuppam, there are three geo-bags — two on the backside and one at
the highest put in within the sea barely away from the coast. These geo-bags cowl
a size of 1.5 kms and have helped shield the seaside from coastal erosion,” knowledgeable
Kumar.

Nevertheless,
the native fishers haven’t warmed as much as the thought of geo-tube luggage and advised Rural
Connection they needed a seawall or groynes. A number of teams have additionally questioned the efficacy
of geo-tube luggage to guard the seaside. They declare geo-tubes have failed to guard
shoreline in a number of different states.

A
wedge reef, nevertheless, has been a welcome intervention.

“Establishing
a seawall or placing groynes is a response to a direct disaster. It solely
shifts the issue elsewhere,” mentioned Banerjee. “Wedge reef is crucial and has
proven a seaside could be protected and restored,” he added.  



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