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Jamuna River

Women washing, clothes, their children and themselves at the foot of the embankment at Sirajganj. Suring the summer, the water reaches almost to the top.

Prior to the late 1700s, the Brahmaputra River flowed farther east by up to 100 km.  It then switched, or avulsed, into a straight north-south route, possibly triggered by an earthquake in 1787.  The small river whose course it usurped was called the Jamuna River.  Now, below the avulsion point where what is now the Old Brahmaputra deviates from the present course, the Brahmaputra is called the Jamuna.  The last two days were upstream of that location.  Now we are downstream of it and thus on the Jamuna River.   Our first stop was Sirajganj.  This town is protected by a stone embankment.  The river has been migrating to the west, threatening the town.  As a result, the embankment now protrudes into the river.  When I was here in 2011 I saw several collapses along the embankment and my class

Meredith and Chris buying snacks and fruit for lunch.

saw them repairing it in 2012.  They now have a lot more riprap at the base to protect it.

We drove along the embankment, a nice promenade, to the ghat and got a fast boat.  Chris had picked out an area with a lot of diversity, so we could efficiently do our sampling.  We checked our notes and found the char that had joined to the very large stable island was not the one we visited in 2005.  That char was now a thin sliver.  We stopped at the head of Katanga Char, only 2 years old, where the high ground was stabilized by grasses and people were growing peanuts and rice on the flanks.  We then crossed a channel to the tail of the next char to the north.  Here, what had been a grass-covered highland had been

Meredith taking notes with our sporty boat in the background.

ravaged by the river.  Tufts of grass that had help on were surrounded by large scours over a meter deep.  The little remnants had the same teardrop shape as the larger chars.  Here and on another small char, we were able to collect all the samples we needed.  We headed for the ghat and our hotel with an outside chance of taking their boat to the char I visited with my students last year.  However, before arriving, we finally found green coconuts for sale.  We had been searching for days for green coconuts. The seller cuts off the top with a machete, inserts a straw and you drink the refreshing coconut water.  Afterwards, he splits it and you can eat the coconut jelly, not yet matured into the coconut meat.  To add to our enjoyment,

All that was left of a vegetated char were mounds anchored by grass that had resisted the flood surrounded by large scours. The teardrop shape was a miniature of the larger chars.

Chris also found a shop selling the wasabi potato chips he had been searching for.  With the extra stop and the slow check-in process, we abandoned visiting the char, but it was still early, so we went into Tangail for some shopping, although we found most shops closed as it was Friday.

For our last stop in the field, we continued south to the confluence, where the Jamuna meets the Ganges to form the Padma River. There are ghats for crossing the Padma and for crossing the Jamuna.  We went to the later, which is smaller now that there is a bridge over the Jamuna.  As the chars shift, so does the ghat.  We had to walk for the last ½ km to the rental boats as Babu’s van could not go.  We started at the southern end of Shivayala Char, a large char at least 30-40 years

I am still drinking the green coconut water while Humayun is already eating the jelly inside the split coconut.

old.  However, the southern end had been eroded and then grew back.  Where we were was only few years old.  From there we went to the next, newer char for examining and sampling as it showed a lot of variety on the satellite imagery.  That done, our next stop was a piece of fluviotourism, the confluence or actual meeting point of the Brahmaputra and Ganges Rivers.  We stopped upstream and walked down the long narrow char.  There were huge scour pits from the turbulence of the two rivers meeting during the monsoon.  The point where the tow rivers met wasn’t as clearly defined as in 2005, but we waded around and found it our final group photo.  Our work was done and it was time to return to Dhaka for some final meetings and a last hartal, and then home.  As usual here, many things did

Boatman at Sirajganj watches Chris load a data point into his GPS. The white wind-blown sand is starting to cover the dry channel behind them.

not go as planned, but with some adjustments, everything we planned got done.

People leaving a crowded ferry at Aricha, by the confluence.
The scours pits formed by swirling eddies of water where the two rivers met during the monsoon.
Lunch on the boat.

The four of us standing a the confluence of the Brahmaputra (left) and Ganges (right) rivers.

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Guamssesy
10 years ago

Aw, this was a seriously nice post. In idea I would like to put in writing like this moreover – taking time and actual effort to create a rather fantastic article?- but what can I say?- I procrastinate alot and by no means seem to obtain some thing completed.

micheal kors

mirza
10 years ago

mike you and your friends are welcome to my home district sirajgonj.i spent my childhood with mighty river jamuna,erosion of river jamuna my forefathers are loosed their houses and cultivated lands.so what,still i love river jamuna.you can find a number pictures in panoramio,posted by my oneself . thanks

mirza
10 years ago

mike you and your friends are welcome to my home district sirajgonj.i spent my childhood with mighty river jamuna,erosion of river jamuna my forefathers are loosed their houses and cultivated lands.so what,still i love river jamuna.you can find a number of pictures in panoramio,posted by my oneself . thanks

Md.Fazle Rabbi Joy
Md.Fazle Rabbi Joy
6 years ago

we the students of gelogy department, university of Dhaka fell very proud to have such legendary teacher Humayun sir.
He has always being an inspiration for the new comer in this subject.