*** The herring-bone pattern of dykes are used to prevent siltation
of the main channel of the river.
They direct the current towards the deeper channel and prevent
erosion of the banks.
But here is a caveat:
If these current diverting structures are made from silt,
they too will get washed out
over time, reverting to the original problem -- of silting.
They have to be made from
rocks for them to be successful. Some silt could possibly be
deposited down-stream of the
the rock 'rip-raps' ( as we call them here in the USA).
These rip-raps can be seen all over the Mississippi and the
Missouri rivers. When the US
Corps of Engineers took over flood control and navigational
waterways maintenance work
on these two major, flooding prone rivers over fifty years
ago, they dredged them for
creating navigational channels and used the rip-raps for
directing the current
towards the dredged navigational channels. They also dammed
the rivers up and built
endless embankments, reducing their flood plains, which, when
breached , have created
untold misery. They continue to do so. The last such episode
was in 1993.
The Missouri river, environmentalists say, was dug, up,
straightened out, embanked
and turned into a 'drainage ditch' by the US Corps of
Engineers, thereby destroying the
side channels , chutes and the sand bars which sustain
habitats for fish and wildlife. They
are now trying to UNDO the damage that was done by man.
Here is a lesson to be learnt:
*** The rivers that created the habitats for man and other
creatures of nature, over millenia,
ought NOT to be turned into drainage ditches.
The chutes, the channels, the sand bars --- ALL play a vital
role in the health of a
river system.
YES, The Yamuna, the Brahmaputra, the Ganga and their many
tributaries MUST be
dredged and deepened. But NOT in a STRAIGHT LINE to turn them
into DITCHES. Most of
silt will have to be deposited in ways to prevent returning
to river the next rainy season.
Rip raps will have to be built.
All could be done. It requires a national commitment.
cm
At 9:51 AM +0530 6/4/07, mc mahant wrote:
*1 Channelizes main flow in the straight course-as should be:
*2 Allows Stormwater from sides unrestricted into river channel as should be:
*3 Creates natural non-swampy high-ground mounds where you can plant
orchards.Their roots may be submerged for 2-3 days at High Flood but
will yield rich fruits due to silting those few days
*4 Allows dynamic Temporary storage for sudden flow rate surges due
to sudden storm upstream.
*5 You do not need to carry the bottom silt to vast distances.
BR
MM
Date: Sun, 3 Jun 2007 20:13:01 -0700
From: [EMAIL PROTECTED]
Subject: RE: [WaterWatch] Cleaning the Yamuna in Delhi - Cleaner
Yamuna : Greener City
To: [EMAIL PROTECTED]
dear mr mahant, i seem to have missed this point last posting:
"Employ 100 floating barge-mounted bottom diggers to dig up the
accumulated putrfiying mass at Yamuna bottom-and deposit fish-bone
like on both banks' lowlying floodplain perpendicular to main
stream."
why specifically the fish-bone pattern? does it act as natural
breakers for the waters more than had the silt been deposited flat
across? does it thereby reduce the amount of silt that can run back
into the river? or any other reason?
regards, benita sen
mc mahant <[EMAIL PROTECTED]> wrote:
To: [EMAIL PROTECTED]
From: [EMAIL PROTECTED]
Date: Sun, 3 Jun 2007 06:11:55 +0000
Subject: [WaterWatch] Cleaning the Yamuna in Delhi - Cleaner Yamuna
: Greener City
Please have a look at the following article - on Cleaning Yamuna in
Delhi.
<http://delhigreens.wordpress.com/2007/06/03/cleaning-the-yamuna-drain->http://delhigreens.wordpress.com/2007/06/03/cleaning-the-yamuna-drain-
in-the-capital/
Do let me know what you think by replying or leaving a comment, I am
thinking of developing a strategy asking the Govt to develop a
demand/supply based policy.
Thankd and Regards
Govind Singh
<http://delhigreens.wordpress.com/>http://delhigreens.wordpress.com
M.Sc.(Semster - IV) Environmental Studies
School of Environmental Studies
University of Delhi
Delhi - 110 007
Catch the cricket action with MSN!
<http://content.msn.co.in/Sports/Cricket/Default.aspx>Click here!
__._,_.___
<http://groups.yahoo.com/group/WaterWatch/message/5764;_ylc=X3oDMTM0dmZzcDQ0BF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBG1zZ0lkAzU3NjkEc2VjA2Z0cgRzbGsDdnRwYwRzdGltZQMxMTgwODk3NzMyBHRwY0lkAzU3NjQ->Messages
in this topic (0)
<http://groups.yahoo.com/group/WaterWatch/post;_ylc=X3oDMTJwdDJldmRzBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBG1zZ0lkAzU3NjkEc2VjA2Z0cgRzbGsDcnBseQRzdGltZQMxMTgwODk3NzMy?act=reply&messageNum=5769>Reply
(via web post) |
<http://groups.yahoo.com/group/WaterWatch/post;_ylc=X3oDMTJlaGR2bzN1BF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA250cGMEc3RpbWUDMTE4MDg5NzczMg-->Start
a new topic
<http://groups.yahoo.com/group/WaterWatch/messages;_ylc=X3oDMTJlbTllZ3JhBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA21zZ3MEc3RpbWUDMTE4MDg5NzczMg-->Messages
|
<http://groups.yahoo.com/group/WaterWatch/files;_ylc=X3oDMTJmaW1nZjEzBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA2ZpbGVzBHN0aW1lAzExODA4OTc3MzI->Files
|
<http://groups.yahoo.com/group/WaterWatch/photos;_ylc=X3oDMTJldmZyZ3FmBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA3Bob3QEc3RpbWUDMTE4MDg5NzczMg-->Photos
|
<http://groups.yahoo.com/group/WaterWatch/links;_ylc=X3oDMTJmZmcxc3JyBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA2xpbmtzBHN0aW1lAzExODA4OTc3MzI->Links
|
<http://groups.yahoo.com/group/WaterWatch/database;_ylc=X3oDMTJjZnVhMWk5BF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA2RiBHN0aW1lAzExODA4OTc3MzI->Database
|
<http://groups.yahoo.com/group/WaterWatch/polls;_ylc=X3oDMTJmZjhxN2ZyBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA3BvbGxzBHN0aW1lAzExODA4OTc3MzI->Polls
|
<http://groups.yahoo.com/group/WaterWatch/calendar;_ylc=X3oDMTJkOGw1b3YwBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA2NhbARzdGltZQMxMTgwODk3NzMy>Calendar
<http://groups.yahoo.com/;_ylc=X3oDMTJkbDk4NGVpBF9TAzk3NDc2NTkwBGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA2dmcARzdGltZQMxMTgwODk3NzMy>
<http://groups.yahoo.com/group/WaterWatch/join;_ylc=X3oDMTJmdDY4ZjVtBF9TAzk3NDc2NTkwBGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA3N0bmdzBHN0aW1lAzExODA4OTc3MzI->Change
settings via the Web (Yahoo! ID required)
Change settings via email:
<mailto:[EMAIL PROTECTED] Delivery:
Digest>Switch delivery to Daily Digest |
<mailto:[EMAIL PROTECTED]
Delivery Format: Traditional>Switch format to Traditional
<http://groups.yahoo.com/group/WaterWatch;_ylc=X3oDMTJkc2lndW8xBF9TAzk3NDc2NTkwBGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwNmdHIEc2xrA2hwZgRzdGltZQMxMTgwODk3NzMy>Visit
Your Group | <http://docs.yahoo.com/info/terms/>Yahoo! Groups Terms
of Use |
<mailto:[EMAIL PROTECTED]>Unsubscribe
Recent Activity
12
<http://groups.yahoo.com/group/WaterWatch/members;_ylc=X3oDMTJmNWRtbnJvBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwN2dGwEc2xrA3ZtYnJzBHN0aW1lAzExODA4OTc3MzI->New
Members
1
<http://groups.yahoo.com/group/WaterWatch/links;_ylc=X3oDMTJnMXZtN2RoBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwN2dGwEc2xrA3ZsaW5rcwRzdGltZQMxMTgwODk3NzMy>New
Links
<http://groups.yahoo.com/group/WaterWatch;_ylc=X3oDMTJlbXRhaXVyBF9TAzk3MzU5NzE0BGdycElkAzk1NDI2MDkEZ3Jwc3BJZAMxNzA1MjkxNzcxBHNlYwN2dGwEc2xrA3ZnaHAEc3RpbWUDMTE4MDg5NzczMg-->Visit
Your Group
SPONSORED LINKS
<'"http://groups.yahoo.com/gads;_ylc=X3oDMTJjM3RjZDg0BF9TAzk3MzU5NzE0BF9wAzEEZ3JwSWQDOTU0MjYwOQRncnBzcElkAzE3MDUyOTE3NzEEc2VjA3NsbW9kBHN0aW1lAzExODA4OTc3MzM-?t=ms&k=South+asia&w1=South+asia&w2=South+east+asia&w3=Fresh+water&w4=Three+gorges+dam&w5=South+ame>South
asia
<'"http://groups.yahoo.com/gads;_ylc=X3oDMTJjN21qMGx2BF9TAzk3MzU5NzE0BF9wAzIEZ3JwSWQDOTU0MjYwOQRncnBzcElkAzE3MDUyOTE3NzEEc2VjA3NsbW9kBHN0aW1lAzExODA4OTc3MzM-?t=ms&k=South+east+asia&w1=South+asia&w2=South+east+asia&w3=Fresh+water&w4=Three+gorges+dam&w5=Sout>South
east asia
<'"http://groups.yahoo.com/gads;_ylc=X3oDMTJjdmFzbHNlBF9TAzk3MzU5NzE0BF9wAzMEZ3JwSWQDOTU0MjYwOQRncnBzcElkAzE3MDUyOTE3NzEEc2VjA3NsbW9kBHN0aW1lAzExODA4OTc3MzM-?t=ms&k=Fresh+water&w1=South+asia&w2=South+east+asia&w3=Fresh+water&w4=Three+gorges+dam&w5=South+am>Fresh
water
<'"http://groups.yahoo.com/gads;_ylc=X3oDMTJjOWp0MmxxBF9TAzk3MzU5NzE0BF9wAzQEZ3JwSWQDOTU0MjYwOQRncnBzcElkAzE3MDUyOTE3NzEEc2VjA3NsbW9kBHN0aW1lAzExODA4OTc3MzM-?t=ms&k=Three+gorges+dam&w1=South+asia&w2=South+east+asia&w3=Fresh+water&w4=Three+gorges+dam&w5=Sou>Three
gorges dam
<'"http://groups.yahoo.com/gads;_ylc=X3oDMTJjaXFtOG9rBF9TAzk3MzU5NzE0BF9wAzUEZ3JwSWQDOTU0MjYwOQRncnBzcElkAzE3MDUyOTE3NzEEc2VjA3NsbW9kBHN0aW1lAzExODA4OTc3MzM-?t=ms&k=South+america&w1=South+asia&w2=South+east+asia&w3=Fresh+water&w4=Three+gorges+dam&w5=South+>South
america
Yahoo! Finance
<http://us.ard.yahoo.com/SIG=12jqahlaq/M=493064.10729649.11333340.8674578/D=groups/S=1705291771:NC/Y=YAHOO/EXP=1180904933/A=4507179/R=0/SIG=12de4rskk/*http://us.rd.yahoo.com/evt=50284/*http://finance.yahoo.com/personal-finance>It's
Now Personal
Guides, news,
advice & more.
Y! Messenger
<http://us.ard.yahoo.com/SIG=12jogt8ma/M=493064.10729668.11333359.8674578/D=groups/S=1705291771:NC/Y=YAHOO/EXP=1180904933/A=3848589/R=0/SIG=12dds2hov/*http://us.rd.yahoo.com/evt=42403/*http://messenger.yahoo.com/feat_voice.php>Talk
it up - free!
Call your friends
worldwide - free!
Yahoo! Photos
<http://us.ard.yahoo.com/SIG=12jb9bj1i/M=493064.10729658.11333349.8674578/D=groups/S=1705291771:NC/Y=YAHOO/EXP=1180904933/A=3848633/R=0/SIG=10p8tommg/*http://photos.yahoo.com>Order
Online
Pick up at Target
Start now
.
__,_._,___ .ExternalClass #EC_ygrp-mlmsg
{font-size:13px;font-family:arial,helvetica,clean,sans-serif;}
.ExternalClass #EC_ygrp-mlmsg table {font-size:inherit;font:100%;}
.ExternalClass #EC_ygrp-mlmsg select, .ExternalClass input,
.ExternalClass textarea {font:99% arial,helvetica,clean,sans-serif;}
.ExternalClass #EC_ygrp-mlmsg pre, .ExternalClass code {font:115%
monospace;} .ExternalClass #EC_ygrp-mlmsg * {line-height:1.22em;}
.ExternalClass #EC_ygrp-text {font-family:Georgia;} .ExternalClass
#EC_ygrp-text p {;} .ExternalClass #EC_ygrp-tpmsgs
{font-family:Arial;clear:both;} .ExternalClass #EC_ygrp-vitnav
{padding-top:10px;font-family:Verdana;font-size:77%;} .ExternalClass
#EC_ygrp-vitnav a {padding:0 1px;} .ExternalClass #EC_ygrp-actbar
{clear:both;white-space:nowrap;color:#666;text-align:right;}
.ExternalClass #EC_ygrp-actbar .left
{float:left;white-space:nowrap;} .ExternalClass .EC_bld
{font-weight:bold;} .ExternalClass #EC_ygrp-grft
{font-family:Verdana;font-size:77%;padding:15px 0;} .ExternalClass
#EC_ygrp-ft {font-family:verdana;font-size:77%;border-top:1px solid
#666;padding:5px 0;} .ExternalClass #EC_ygrp-mlmsg #logo
{padding-bottom:10px;} .ExternalClass #EC_ygrp-vital
{background-color:#e0ecee;margin-bottom:20px;padding:2px 0 8px 8px;}
.ExternalClass #EC_ygrp-vital #vithd
{font-size:77%;font-family:Verdana;font-weight:bold;color:#333;text-transform:uppercase;}
.ExternalClass #EC_ygrp-vital ul {padding:0;} .ExternalClass
#EC_ygrp-vital ul li {list-style-type:none;clear:both;border:1px
solid #e0ecee;} .ExternalClass #EC_ygrp-vital ul li .ct
{font-weight:bold;color:#ff7900;float:right;width:2em;text-align:right;padding-right:.5em;}
.ExternalClass #EC_ygrp-vital ul li .cat {font-weight:bold;}
.ExternalClass #EC_ygrp-vital a {text-decoration:none;}
.ExternalClass #EC_ygrp-vital a:hover {text-decoration:underline;}
.ExternalClass #EC_ygrp-sponsor #hd {color:#999;font-size:77%;}
.ExternalClass #EC_ygrp-sponsor #ov {padding:6px
13px;background-color:#e0ecee;margin-bottom:20px;} .ExternalClass
#EC_ygrp-sponsor #ov ul {padding:0 0 0 8px;} .ExternalClass
#EC_ygrp-sponsor #ov li {list-style-type:square;padding:6px
0;font-size:77%;} .ExternalClass #EC_ygrp-sponsor #ov li a
{text-decoration:none;font-size:130%;} .ExternalClass
#EC_ygrp-sponsor #nc
{background-color:#eee;margin-bottom:20px;padding:0 8px;}
.ExternalClass #EC_ygrp-sponsor .ad {padding:8px 0;} .ExternalClass
#EC_ygrp-sponsor .ad #hd1
{font-family:Arial;font-weight:bold;color:#628c2a;font-size:100%;line-height:122%;}
.ExternalClass #EC_ygrp-sponsor .ad a {text-decoration:none;}
.ExternalClass #EC_ygrp-sponsor .ad a:hover
{text-decoration:underline;} .ExternalClass #EC_ygrp-sponsor .ad p
{;} .ExternalClass EC_o {font-size:0;} .ExternalClass .EC_MsoNormal
{;} .ExternalClass #EC_ygrp-text tt {font-size:120%;} .ExternalClass
blockquote {;} .ExternalClass .EC_replbq {;}
BENITA SEN
JOURNALIST & AUTHOR
<http://us.rd.yahoo.com/mail/uk/taglines/hotmail_com/nowyoucan/pc_mag/*http://us.rd.yahoo.com/evt=40566/*http://uk.docs.yahoo.com/nowyoucan.html>All
new Yahoo! Mail "The new Interface is stunning in its simplicity and
ease of use." - PC Magazine
Want to look great? Get expert opinion on beauty and skin care.
<http://content.msn.co.in/Lifestyle/AskExpert/Default01.htm>Ask the
expert!
_______________________________________________
assam mailing list
[email protected]
http://assamnet.org/mailman/listinfo/assam_assamnet.org
_______________________________________________
assam mailing list
[email protected]
http://assamnet.org/mailman/listinfo/assam_assamnet.org
