Pages

Wednesday, 28 December 2011

Coastal Andhra Pradesh undergoing major geomorphological changes: New beaches appearing, some disappearing: Upputeru shifting its course unidirectionally

Syed Akbar
Hyderabad: The coastal region in Andhra Pradesh is fast
changing with the area under beaches either increasing or decreasing,
and rivulets shifting their course. The sea is eating into lush green
lands at certain places.

The geomorphology data for the last four decades available with the
city unit of the Geological Survey of India indicate that the mouth of
the Upputeru rivulet has unidirectionally shifted very rapidly
westwards by about 3 km in the last 30 years, eroding more than 100
hectares of high-yielding coconut gardens near Chinnagollapalem. There
has been a growth of about 3 km long beach near the Upputeru river
mouth and formation of bars and shoals in the vicinity.

The coastal tract between the two distributaries channel mouths of the Gautami Godavari at Malatithippa is subjected to both erosion and accretion, though the latter is dominant.  The prominent bar, which existed in 1971, and the northeastern side of the Gautami-Godavari mouth disappeared. Spits are developing on left mouth of the
Vainateyam and the Vasishta.

The GSI has summerised the research works (GSI Memoirs) since the
opening of the Hyderabad centre in 1973. An analysis of the data
reveals that the delicate geomorphology of the coastal region is
undergoing visible changes at a rapid phase. According to the GSI
data, beach growth up to 1 km wide has been noticed along the 10 km
stretch from river mouth of Gautami towards west, while the shoreline
near Machilipatnam is subjected to erosion. The tidal creek mouth is
constantly shifting northwards with respect to the Machilipatnam Port.

The GSI city team has found erosion of bars on one side and accretion on the other side of the estuary of the Penna River. A spit is emerging on the Swarnamukhi River mouth. There is beach accretion further south near Kondurupalem.

“Accretion in the form of bar and shoal is seen at the confluence of
Vainateyam, Vasishta, Krishna River northeast distributary and also
the outfalls of Enamadurru drain- straight cut, Kunavaram straight
cut, Peddalanka drain etc. Due to the formation of the Kakinada spit,
a vast area of shallow sea is being separated from the main sea,” the
GSI Memoirs points out.

The GSI has noticed sea erosion north of Uppada village, where 100 m
wide beach was eroded in 14 years. Besides, presence of a wave-cut
platform at 2.5 km southwest of Uppada, and erosion of beach at
Mulapeta are the important evidences of sea erosion.

No comments:

Post a Comment