Is it soap suds?

[welch100]

Periodically, we get what looks like a quantity of soap suds washing up on our island beach. This may sounds like a stupid question, but I've always wondered if that phenomenon really is soap. Is there some other cause? How would we find out? Take a water sample to Concord for testing?

Thanks!

[LadyoftheLake]

Welch,

I have seen those soapy looking masses many times. I was told it was from "algae blooms" caused by acid rain. I was curious enough to search for more info and here is a link from the gov/epa

http://www.epa.gov/acidrain/effects/surface_water.html

I wish that someday it will disappear by helping with cleaner air.

Happy Boating to all. :)

[Lakegeezer]

The NH DES has an article about lake foam (http://des.nh.gov/organization/commissioner/pip/factsheets/bb/documents/bb-5.pdf). Here is part of it.

The foaming of surface waters on lakes is not a new phenomenon. It is a natural process that has been going on for a long time. Foam is created when the surface tension of water (attraction of surface molecules for each other) is reduced and the air is mixed in, forming bubbles. Man-made agents can also reduce surface tension. All lakes contain organic matter, such as algae and plants, and when these decompose they release cellular products (surfactant) into the water, which lessons the surface tension. When the wind blows, the waves on the lake agitate this surface agent, thus transforming it into sudsy white foam. Currents and boats also mix air with the organic compounds present in the lake to produce foam.

While the acid rain creates problems for the lake, it also helps to keep the zebra muscles away. The acid makes it hard for them to form calcium shells. I believe the rain has become less acidic since the steel mills shut down, but coal-fired power plants still contribute acid to the air upstream. The NH DES also has an article on acid rain (http://des.nh.gov/organization/divisions/air/tsb/tps/acidrain/categories/overview.htm) and lists some water bodies with impact. Lake Winni is not on the list, but it probably should be.

[Merrymeeting]

I participate with a group that does weekly water testing on Merrymeeting Lake. The samples and results are sent to the UNH Extension Service. A quick search shows that the same is done on Winnipesaukee, in multiple locations.

http://cfb.unh.edu/programs/LLMP/nhllmp.htm

http://winnipesaukeegateway.org/monitoring-the-lake/introduction/

I did not find any of the 2012 water quality reports for Winni. The Merrymeeting one can be found here. http://www.mmlake.org/MMLA_documents/Merrymeeeting%20Lake%202012%20Report.pdf

The good news is that we have been getting pH readings of 7.1-7.3 all year, consistent with other years. As much of this water flows into Alton Bay, I would expect this to be true in that area also.

While many other factors need to be considered when assessing these numbers (buffering capacity, sample depths/areas/locations, etc), the numbers indicate that acidity of our water is not an issue...yet.

[welch100]

to all for the great info! I'm so glad to hear it's not soap after all.:)

[rgilfert]

We are situated on the west end of Rattlesnake on the Broads side and have noticed that when the foam accumulates off shore it tends to occur in virtually the exact same position every time. In our neck-of-the-woods the foam manifests itself as a long (1/2 Mi +/-), narrow (20' +/-) band that is consistently approx 100' offshore. We had a mooring installed this year and we have noticed the the foam band consistently passes right past the mooring ball (i.e .it forms almost exactly 100' from shore). There must be some reason explaining why it (i.e. the long band of foam) seldom moves closer to shore. Possibly it has something to do with the fact that there is a shelf off shore on our end of the island that extends out perhaps 150' from the shore and then the bottom drops off quickly. Despite the fact that our mooring is about 100' from shore it is only in 7.5' of water...and if you go out perhaps 50' further it becomes deep quickly. We feel that the pattern/location of the foam band must have something to do with this natural shelf/ledge...but can't for a minute hazard a guess as to why. Does anyone know?

[PaugusBayFireFighter]

We are situated on the west end of Rattlesnake on the Broads side and have noticed that when the foam accumulates off shore it tends to occur in virtually the exact same position every time. In our neck-of-the-woods the foam manifests itself as a long (1/2 Mi +/-), narrow (20' +/-) band that is consistently approx 100' offshore. We had a mooring installed this year and we have noticed the the foam band consistently passes right past the mooring ball (i.e .it forms almost exactly 100' from shore). There must be some reason explaining why it (i.e. the long band of foam) seldom moves closer to shore. Possibly it has something to do with the fact that there is a shelf off shore on our end of the island that extends out perhaps 150' from the shore and then the bottom drops off quickly. Despite the fact that our mooring is about 100' from shore it is only in 7.5' of water...and if you go out perhaps 50' further it becomes deep quickly. We feel that the pattern/location of the foam band must have something to do with this natural shelf/ledge...but can't for a minute hazard a guess as to why. Does anyone know?
Just guessing, since the surfactant is produced by decomposition of plant material, could that shelf provide an abundant area of algae and other plant life that causes a large release of the surfactant which would cause the foam?
Just a guess

[garysanfran]

It says although salt water, the salt is NOT the reason for the foam...

http://geology.utah.gov/surveynotes/gladasked/gladfoam.htm

[garysanfran]

http://des.nh.gov/organization/commissioner/pip/factsheets/bb/documents/bb-5.pdf

[ApS]

to all for the great info! I'm so glad to hear it's not soap after all.:)
Now, after decades of resistance, even dishwasher soap must meet higher biodegradable standards, so soap would be a very unlikely cause of foam in this lake.

The "test" is to scoop up the suds and smell them. I've never detected soap odor, even before any Phosphorus standards came into being.

Perhaps it was in the old forum, but I'd written of Langmuir Streaks before; however, Google doesn't return Langmuir Streaks—but Langmuir Circulation.

(News to me). :confused:

http://en.wikipedia.org/wiki/Langmuir_circulation

In especially strong winds, I've counted as many as 11 parallel streaks off our particular shoreline. By October, the foam can appear in long cylindrical clumps—much like beige-colored swim noodles.