2. Why foaming happens?

Due to presence of SURFACTANT in water, from:  

  1. Industrial effluent
  2. Household laundry detergent and cleaning
  3. Dead and decaying plants


Bellandur lake had 15-20 ppm of anionic surfactant. Most of it was from untreated Household sewage (40% of 530MLD inflow).


It is possible that surfactants get accumulated in the lake sediment in significant proportions. This when churned by heavy runoff, has a very great potential to form large quantities of foam. 

Fig 3: Hypothesis : surfactant desorption from sediment due to rainfall



3. Sediment Characterization


  1. To  charecterize Bellandur sediment
  2. Sorption kinetics of anionic surfactant(SDBS) on sediment.


Fig 4: Sampling locations of sediment around Bellandur Lake

Aim 1: Sediment Characterization

Table 1: Sediment charecteristics


Inference 1: 
  1. The Bellandur sediment was predominently sandy.
  2. Sample B2 and B4 had highest organic carbon content , comparable to STP sludge
  3. Bellandur sediment had adsorbed anionic surfactant at ranges 2.9-4.9 g/kg (dry wt) 


Aim 2​: Sorption Kinetics 

Sediments 0.3 g (d.w.) were shaken with 50 ml of 10 ppm SDBS soln for various periods of time. After centrifuging at 10,000 rpm for 10 min, SDBS in the supernatant  was determined. 


Fig 5: Absorption kinetics of surfactant on sediment with respect to time

Inference 2:
  1. Carbon content in sediment was proportional to amount of anionic surfactant adsorbed    [Sludge>B2>B4>B5>B3>B1]
  2. Absorption time (6 hours) << HRT of Bellandur lake (10 days ).This ensures no washout of surfactant from lake.



1. Foaming Lake or Snowy Swiss locale??

Fig 1: Foaming Urban Indian Lake- Bellandur Lake. Foam reaches 6-7 feet height, disrupts traffic and emits smell.


When foaming happens?

Fig 2: News clippings showing foaming occurs only after rain



4. Role of sediment in foaming

Aim : To analyse foam stability due to sediment

Different conc. of sediments were foamed with SDBS soln. (10 ppm).  Time needed for the foam to subside was indicative of foam stability


Fig 6: Foam persistence time with varying sediment concentration



1. Increasing sediment concentration added to foam persistence time. Increased surfactant concentraion noted in supernatant

This proves that surfactant gets desorbed from the sediment.

2. beyond 20 g/l total solid conc. the foam persitence dropped.This is due to viscous drag provided by sediment particles.






5. What did we find?

  1. Household laundry detergent  gets absorbed onto the Bellandur sediment.
  2. Absorption of surfactant is proportional to the carbon content in the sediment
  3. Rain desorps the surfactant and adds to the foaming intensity


Is there any novelty?

Absolutely!  This is the first study on sediment of foaming waterbody. We also address the reason behind seasonality of such foaming events.



Your iPoster has now been unpublished and will not be displayed on the iPoster Gallery.

You need to publish it again if you want to be displayed.

You must be registered to publish your poster.

Please visit www.agu.org/Fall-Meeting/Pages/Register-Housing/Registration-Rates to get registered

If you have recently registered, you may have to wait up to 10 minutes to be able to publish.

If you are still unable to publish, please contact AGU at: [email protected]

Sorry but time is up!

Because of maintenance we have just saved your content and will within a few minutes logout all users and restart our server. We will be back in a moment.

Sorry for the inconvenience!

Because of maintenance we will within a few minutes restart our server. We will be back in a moment.

Sorry for the inconvenience!

Poster editing is now closed, but you can still:

• Add an Audio Presentation
• Arrange a Chat or Video Session
• Use My Settings to Change your Publishing and Sharing Rules, and view Statistics

Please address any questions to [email protected]


Contact Author

Get Poster



Please enter your email address in the field below and a link to this iPoster will be sent to you.

NOTE: Your email address will be shared with the author.