Residential Wastewater Systems

Have you contacted anybody about this, maybe someone in the West Indies.

What have you done so far?

I am looking for a Distributor. DAJJ provides MBR wastewater systems.

Are septic tanks and drain fields feasible?

No.

So, exactly what are the waste streams? Where would they go to?

Some shipboard sewage treatment systems might be the right size for your situation. It has been a long time since I was involved with those, but "Microphor" was the brand name of such a system on a 43-crew crab boat on which I was chief engineer. I think they made smaller units as well. A Web search may turn up others.

Why on earth go with a residential WWTP? They are expensive and maintenance intensive. Repairs can often exceed the principal cost to procure the WWTP. Also, their track record for meeting effluent guidelines is not too good. Ditto, for reliability.

I would prefer to install what is called a "shallow Absorption trench system" or a "Mound System" with a precast concrete septic tank and distribution box. The type of system installed is highly dependent on the depth of the seasonal high groundwater level or depth to underlying rock. They are very hands off and maintenance free. Depending on the magnitude of the wastewater stream (waste load and flows), expect to just pump out the septic tank every 5-to-10 years on average if it is used year round. You can extend that period by flushing down a few yeast packages once a month so that the anaerobic bacteria digest the sludge in the bottom of the septic tank.

Expect a well built and maintained shallow absorption system to last over 20 years before it has to be rebuilt or a new one built along side of the old one. Make provisions to include enough reserve space for a future system replacement.

Doesn't Barbados have minimum wastewater disposal statutes that you have to adhere to? You had better check to see if that is the case before construction any wastewater disposal system.....

My first choice would have been a Centralised MBR Wastewater System. However, that's not a consideration of the Developer. Each home must have its own WWTP with each homeowner responsible for the O&M of their system.

I think everyone is going about this the wrong way. A mechanically-based WWTP is energy and mechanically intensive. In the long run, it's going to cost each home owner a large bundle of cash to keep it running over the years.

Believe me, Iknow these things as I'm a Licensed Professional Engineer and have my Doctorate degree in Environmental Engineering. I design WWTP and residential subsurface wastewater disposal systems routinely.

I do agree with you about the cost to the home owner. That's what I am trying to avoid, so I need an economical system that will produce quality treated effluent.

I like and have considered Norweco singular systems, but Home owners will not accept that energy cost to their monthly electrical power bill.

I was quite certain I saw residential systems online that use Oxygen from the atmosphere injected through the inlet pipe to aerate the Mixed Liquor. However, I am not finding these systems online.

The main issue is to have a reliable efficient WWTP that will be economically viable to the home owner.

It appears Dajj Water Systems wants to be able to reclaim the waste water for domestic use. Probably for flushing the toilets again, or even better re-using the water as potable water.

It is a noble idea, but is it cost effective as a stand alone system for an individual home owner?

I have seen some waste water recycle on a small scale, where the ptable water was brought in by truck every day, and the waste water was treated and filtered and then used for flushing the john again - it was not very appealing and the reused water was definitely coloured.

Your response was very much the same as I would have replied.

However, there appears to be a critical lack of water in the Barbados.

http://www.mcgill.ca/files/bioeng/AmelieEdmundAlain2005.pdf

This article appears to provide some ideas along the lines of the poster's requirements.

Some other references:http://www.cep.unep.org/pubs/Techreports/tr43en/Barbados.htm
Dajj Water Solutions:
http://www.facebook.com/video/video.php?v=10150690313192437

I think you should examine the code for your area. I have run septic beds for years without any "horrors". And this was in Canada, which freezes a meter deep every winter! I had it installed by a certified installer who works to code. That is your best and cheapest option by far. I replaced the filter bed when I bought this house I am living in now 30 years ago...it was all clay tile which had been installed sometime in the '30s. Plant grass, or flowers. Or carrots. I don't know why they would EVER wear out. Mine are still working fine, and its been some thirty years.

That being said, the nature of septic is that it uses anerobic bacteria to break down the bad stuff...adding oxygen would simply create a smelly mess. If your residences are very rustic, there are some very useful composting privies existing in the market place. These use oxygen, and are often simply "flushed" with dry leaves. You avoid the ammonia by using urinals, which is disposed of separately. The whole earth catalogue has some. They are also VERY inexpensive to install, and operate. The fancier ones for indoors use some electricity to dry the solids...turns out that after they have been dried to dust, they don't take up much room. BUT the electric bill is there, if not very high, and you have to hire a guy to clean it out once in a while.

Do like the Cap'tn said, and find out what is normally done in your area. There are several options. Cheap....well....just don't contaminate the fresh water wells. People are depending upon you to do it right.

I built an underground home and installed a Makeway Plastic Septic system ( www.makewayplastics.com) This system treats the sewage in such a manner that the end product is ( Near Drinkable) In Ontario it was legal to let this effluent into a waterway however we installed a weeping bed of septic tank specifications just to be extra safe. There are photos of the installation on the site ( www.domehome.ca). Usual disclaimer.

Thanks I will look at their systems.

I am also looking at available systems on www.wte-ltd.co.uk.

I greatly appreciate all the feedback on this topic.

Thanks.

Check out Advantex Systems at www.orenco.com.

Thanks. I am on the website right now.

I tend to fully agree, Capt. Moosie. I think dajjwater had better look into composting toilets, and hope the island is large enough to support whatever he installs.

Decades ago before introduction of detergents by MNCs for cleaning- in India we had eco friendly, washing solutions - for washing hands and vessels etc. So the water from washbasin used to be diverted into the garden for plants directly. There are many plants which need plenty of water. Now MCs which developed detergents as efficient cleaning solutions need to develop another cheical to neutralise tehse- so taht the same water can go into garden.

As far as sewerage water - it is discharged into teh main outlet of city's sewaerage line. May be you could consider pumping washbasin & washing machine water into a separate overhead tank for discahrging intotoilet tanks. It may still save lot of water.

Since electric energy is a problem ,you should steer away from all the commercial type package plants. A septic tank and tile field is Good if the soils drain well or the water line is not too high. If the groundwater is high then you need a sand mound but they use dosing pumps.Depending on how long the electric is turned off this could still work if you size the dosing tank large enough to hold the flow volume. Look into a Clivus mulstrom waterless composting toilet with a septic tank for the gray water into a leaching bed. Also look into artificial reed beds if the soils do not percolate.

You don't necessarily need a "dosing pump" to lift the wastewater up between a septic tank and the headworks (ie, distribution box) of the tile field.

Depending on the actual LIFT height, you may be able to utilize a "Dosing Siphon" inside the septic tank. They do not require any electricity whatsoever.

Here's a link to a manufacturer of automatic dosing siphons (there are others):

http://www.siphons.com/index.html

Here in St. Thomas we have similar problems like Barbados. Water is scarce, drainage is poor, and electricity is expensive. I had a Microphor system on a dive shop, too close to the water for anything else. It worked fine, they are rated for marine use, safe to discharge into the ocean. It has a chamber with vertical columns of redwood chips in pvc tubes to support aerobic bacteria that consume the waste. The discharged effluent is post-chlorinated for marine use, or fed to a small drain field.

Grey water is not so difficult to deal with, since it usually doesn't contain dangerous bacteria, usually just soapy water. The plants love it . The condos here use it to water the grass, (or bananas) no problems.

Setting up a dual system is the trick. Keep the grey water separate from the sewer. It's not that hard to process some grey water back to flush the toilets, saves a lot of potable water. Otherwise 'well' water which is not quite potable because of salinity can be used for flushing, too.

Thanks Mike for your contribution.