Purer Streams - Engineered Waterway Regeneration

Good morning, Mr. Gee.

I have some expertise in designing sluice gates, because I have been working for one of the biggest Companies of this field in Spain.

For a starting, I would like to have an schematic layout of the waterway regeneration system you propose, and the volume of the rock filled tanks.

I understand that the water to be regenerated should be pumped from one tank to the other one, in cycles of two to four hours, and so on. How many times should the water be pumped between the two tanks?

I understand that one tank stays two to four hours exposed to the air to let the bacteria to become aerobic, and then is filled with the water of the other tank. After several cycles, the regenerated water is given back to the river, in this application, or to the regenerate water distribution system, in other cases.

Is it like that?

My e-mail is apr@arrakis, please contact me directly.

Many thanks,

Arturo Pérez

Dr. Industrial Engineer

Dear Mr. Perez,

It would help if this discussion continue to happen on CR4 so that fellow members also learn more about this very interesting and useful application.

Gracias,

Qaiser

In septic work tanks are required and so is pumping. That system is essentially someone else's intellectual property and I wish them every success.

The concept I am working to develop uses rock filled open impoundments and nearly natural flow patterns for the fields. During spring flooding seasons all fields would naturally fill to capacity greatly relieving downstream peak flood levels. During normal flows each field would fill and drain on a cyclic schedule that represents some compromises between flow volume field volume and treatment optimization.

In terms of the environmental biology point of view we are talking about engineered wetlands, flood plains, or serge. As natural a system as possible but with greatly improved oxygenation and purification of the native flows.

In this country the army corp of engineers has regulatory authority over these types of projects but the work is typically privately contracted. The mine waste applications are fully funded and some projects have been awarded and completed but many many projects remain and there have been quality and reliability issues raised with some of the existing installations. The more highly engineered the systems the greater the reliability problems have been so I feel this low tech approach relying on enhanced microbial action has merit.

Sincerely,

Mr. Gee

This sounds like you want to apply a recirculating sand filter to the creeks and rivers. There is a large amount to research that has been done by EPA and several states. You may want to look at this further because creeks and rivers, at least in Kentucky, are so clean that this process may have a hard time getting started. There needs to be a good supply of bacteria for this to get started and it needs to be fairly constant to work properly. I would expect that varible rates of flows and concentrations will be the biggest stumbling blocks.

I've designed and built several recirculating sand filters for decentralized sewer systems in Tennessee. I've also visited a site in Alabama where TVA has been studying one version of the system you describe.

The efficacy of the application you propose depends on several factors - flow (volume per unit time), the "strength" of the water you intend to "cleanse" (how "dirty" is it?), what are the constituents in the dirty water (heavy metals, acid, organic matter), and how clean do you want it to be (this is a factor in how many cycles it must undergo).

Biological processes will not fix everything, and these things are not maintenance free. For instance, if heavy metals could be captured you have to think through the process of occasionally cleaning or replacing the media without releasing a huge dose of the offending stuff and creating a new problem.

The size of your impoundments could be rather large - capable of detaining 2 to 4 hours of flow. Where are the impoundments to be constructed (a remote mountain stream or at a mine site) and how does re-routing the flow affect the ecology of the stream (this may not matter much if the stream is already dead from pollutants).

Designing sluice gates to redirect the flow ought not be that difficult.

Do you have design parameters in mind - starting with the quality of the influent and desired quality of the effluent?

There is a new machine that can oxygenate sludge streams, in-line, very efficiently that creates an aerbic environment.

It is in the development stages but field tests have been extremely good in reducing sludges into soil in record time.

Contact Mike Mitton at 519-758-7208 for more details.

SL

the web site is www.mittonvalve.com

for DAF process.

Gentlemen

I live in El Salvador, and 90% of our rivers are highly contaminated, please send a link for where can we find this valuable information, are there any NGO´s thta transfer this kind of technologies?

Thank you

To all,

This is a very interesting topic indeed. I am wondering how this would work. Let's say that we wanted to remove 75% of the organic material from a stream or river. Would this require all of the water to go through this filtration system? Also, wouldn't flood control involve some sort of dam(n) construction? If so, then wouldn't this have some environmental impact in that area (construction, additional roads, wildlife, fish, birds, etc...)?

How does one improve the water quality (with this type of method) without significant impact to the environment?

Birdman

Sand filtration is just that. This approach is different. Filtration is not necessarily a project goal. Sedimentation can and does occur in streams all the time and dealing with it in this proposed system is one of the greater challenges.

The practical results obtained in similar systems to date indicate that the high surface area to contained volume in a rock filled tank or impoundments provide a very good substrate for bacteria growth. The bacteria feed off the dissolved or suspended organics and reduce the yuck that is prone to decomposition.

The entire flow volume of a stream does not need to be treated in a single stage at a single sight in most cases. As I envision the system oxygen absorption (a metabolic process and a fluid dynamic one) by the wet slime on the rocks would reduce the pH of the treated water dynamically without chemical admixture. Including limestone rock would create the possibility of bacterial and chemical reduction of the pH of the native flows.

Practical experience with contained effluent treatment systems indicates that fouling of the tanks or fields is substantially less of a problem than might be anticipated.

Substantial areas of low lying flood prone wetlands adjacent to native flows would have to be engineered to support the several goals of the project which would include flood prevention, oxygenation, cleansing, and possibly aquaculture.

Projects that are specific to mine waste remediation would probably have to be constrained to a single large specific site and be more highly engineered. Projects that have more diverse environmental improvement goals could be more dispersed along the flow.

Seasonal flooding must be anticipated in many instances so a very reliable low tech means of flow switching is required or the switching and pumps will fail due to seasonal inundations. Because of the field volume to flow volume relationship these projects would involve fairly large areas that are already in some cases wetlands or flood plains. The pumping would ideally be accomplished through gravity driven filling and draining cycles which means that there must be a certain amount of fall, head, or run in the site location near the stream or river.

The justification for the project rests on two main points. First these engineered wetlands have the potential to be 10 times as efficient at bio-remediation as the native streams are. Secondly the expansive, nearly level flood fields with control systems means that there is a real potential for flood remediation in this system as opposed to flood control systems. Finally, there are a number of other possible benefits that might be realized from promoting biodiversity in the serges and supporting migratory, amphibious, and other species.

The primary difficulties that can be anticipated are the wetlands possibly supporting the proliferation of mosquito's and the sedimentation of the fields. Since several members have made good contributions about the controls I would also welcome discussion of these issues as well.

Thank you for all your contributions to this discussion.