Sediment Control System
A sediment control system for a contaminated source, comprising an intake system for reversibly diverting flow from the contaminated source to a pipeline extending from the intake system to a plurality of spaced discharge outlets in a low turbulence zone within a water body to minimize mixing of the contaminated source flow with the water body. The source may be a stream, an industrial discharge, a construction site siltation settlement pond, a community storm drain, or a mine tailings source, The water body may be a lake, an ocean, a settlement pond, or a water reservoir.
The present invention relates to water treatment. In particular, the invention relates to systems for reducing contamination of water bodies by silt or sediment.
BACKGROUND OF THE INVENTIONSuspended silt or sediment in water bodies can be a significant issue for fish habitat and human water consumption. Small quantities of silt in streams entering a large water body can result in contamination of the entire water source. Large water bodies can be contaminated by small sources of contaminated silty water. One or a few small streams contaminated with silt can cause widespread silt issues within a much larger water body such as a lake or reservoir.
Silt in water reservoirs can be difficult and expensive to resolve once the entire water source has been affected. Even minute levels of suspended sediments can be a significant health concern and an expensive issue to resolve. Water quality issues arc becoming a much more heavily scrutinized public health issue. Acceptable silt levels in drinking water reservoirs are constantly being reduced to avoid any potential issues.
An easy and inexpensive solution to suspended sediments would drastically reduce water treatment costs.
The present invention will be described in further detail in accordance with the following drawings where;
It is to be expressly understood that the description and drawings are only for the purpose of illustration and as an aid to further clarify the descriptive text of the present invention and are not intended to limit the parameters and potential applications of the invention.
SUMMARY OF THE INVENTIONThere is provided a sediment control system for a silt contaminated source, comprising an intake system for reversibly diverting flow from the contaminated source to a pipeline structure having proximal and distal ends, the pipeline extending from the intake system to a low turbulence zone within a water body; wherein the distal end of the pipeline further comprises a plurality of discharge outlets selectively spaced to minimize mixing of the contaminated source flow with the water body.
The pipeline structure may include a pipeline submerged along the bottom of a water body, the system further comprising submersion means for maintaining the distal end of the pipeline near the bottom of the water reservoir. The submersion means may be one or more concrete weights distributed along the distal end of the pipeline.
The pipeline structure may include a floating horizontal pipeline portion extending from the edge of the water body to a position vertically above the low turbulence zone, and a submerged vertical pipeline portion extending from the floating portion to the discharge outlets at the bottom of the water body.
The contaminated source may be a stream, an industrial discharge, a construction site siltation settlement pond, a community storm drain, or a mine tailings source. The water body may be a lake, an ocean, a settlement pond, or a water reservoir. The intake system may be a dam or a head pond.
The system may include means for replenishing the watercourse, which may be a water pumping system to move water from the water reservoir to the watercourse downstream of the intake system.
The intake system further may include a flow control system, a sediment monitoring system, a flow directional control valve, and a screen for removing large granular particles and debris.
The sediment control system may include a fish diversion structure to allow fish to bypass the intake system, an overflow management system, and flushing means for clearing residual sediment from the pipeline.
There is further provided a method of controlling sediment in a water body fed by one or more contaminated sources, comprising the steps of diverting a portion of the silt-contaminated water of at least one of the silt-contaminated streams into an intake system; transferring the silt-contaminated flow into a pipeline extending from the intake system to a low turbulence zone within a water body; and discharging the silt-contaminated flow through a plurality of selectively spaced discharge openings in the distal end of the pipeline. The method may include the additional steps of monitoring the sediment levels in the one or more contaminated sources; adjusting a directional flow control valve to select the portion of the contaminated water to be diverted into the intake system; and replenishing the contaminated sources with water piped from the water body.
There is also provided the use of the sediment control system of the invention for reducing silt contamination in a stream, for safely discharging contaminated industrial sources, for storm drain discharge, for industrial effluent settlement, and for mine tailings settlement.
DETAILED DESCRIPTION OF THE INVENTIONThe invention comprises a sediment control system designed to manage the suspended sediment problem created in large lakes, reservoirs or other water bodies by contaminated sources, such as contaminated streams, entering the water body. Small streams with relatively small volumes of water but with significant sediment content can contaminate much larger reservoirs. As well, larger streams can carry sediment and cause contamination. Sediment in reservoirs used for drinking water can be a costly problem to deal with for communities. Even small levels of sediment can create health hazards. Prior art solutions require costly filtration systems to deal with the sediment.
Drinking water contamination is becoming a critical issue in many parts of the world. Industrialization and increasing pollution are continuing to threaten already heavily utilized water sources. Excessive sedimentation further complicates the pollution issues. In many advanced countries, the sediment issue and resulting water quality concerns are increasing in priority as the evidence of their impacts increases. Acceptable sediment levels in drinking water reservoirs are continually being lowered. As a result, an inexpensive and effective solution to excessive sediment is increasingly important. The more effective and inexpensive the solution, the more widely it will be implemented.
Small streams can easily be heavily laden with sediment under certain runoff conditions. Even small streams can easily contain sufficient sediment to contaminate much larger water bodies such as lakes and reservoirs. Fine silt and clay particles can remain in suspension for very long periods. Large water bodies are subject to continual wind, current and flow conditions which complicate the settlement of suspended sediments.
Small or large contaminated streams entering large water bodies can create significant sediment issues which are very costly to resolve and can persist for long periods of time.
The proposed sediment control system involves an intake structure on the problem stream which directs any contaminated flows into a pipeline. The pipeline is of sufficient size to carry the normal stream flow. The flow would be selectively directed into the pipeline when the stream is contaminated. Otherwise the stream flow would follow the normal route to the reservoir. The intake structure would contain a sediment monitoring system and a directional control valve.
As depicted in the drawings, according to one embodiment, the flow from the contaminated source 2 is diverted by an intake 4 into a pipeline 6. The pipeline runs from the intake out into a water body 8 such as a lake and may secured to the bottom 10 of the water body with concrete weights 12. The water at the lake bottom is generally much more static and less prone to constant circulation and mixing, presenting a low turbulence zone 14 within the water body. In contrast, surface water is subject to constant movement and mixing. The pipeline has a plurality of discharge outlets 16 located close to the distal end 18 of the pipe to distribute the sediment laden water over a given area. The discharge system would be designed to distribute the water over an area while minimizing the mixing with the larger reservoir. The contaminated water would remain in the relatively static bottom layer, the low turbulence zone and would settle out much more quickly. The discharge system preferably would be in the most appropriate location in the reservoir. This would generally be a large area located at a deeper elevation with minimal current and circulation.
The proposed sediment control system may work for other types of contaminants that could be deposited appropriately in deep lake bottoms. These would include mine tailing treated water or, in some cases, mine tailings themselves.
The solution of the present invention is a system in which the contaminated stream flows may be directed into a pipeline which runs out into a water body and is weighted to sit on the bottom of the water body. The pipe would extend down to the bottom of the lake where the water is relatively still. The pipe would have openings at the distal ends to allow the sediment contaminated water to discharge 21 from the pipe.
The contaminated water would be dispersed over a distance to ensure the flows exiling the pipe were relatively slow moving. This would minimize the disturbance and mixing of the contaminated water. By minimizing mixing, the risk of affecting the entire water body is reduced.
If a large and deep lake receives small inflows of contaminated water, it would be relatively easy to contain the problem. In other lakes which are smaller, shallower and subject to larger contaminated flows the design of the system would need to be more carefully managed to minimize mixing. Each location would require individual assessment and management.
The depth of the water body and the amount of flow in the lake would affect the water movement at various depths in the lake. The amount of contaminated water relative to the total flow would have to be evaluated. Each scenario would be different as would the effectiveness of the proposed solution.
Stream flows would be directed into the pipe only when the water is contaminated. Normal clean stream flows would be directed down the normal stream route. A metered monitoring system and directional valve 22 would need to be installed to determine and control flow direction.
Fisheries issues would need to be considered. Measures would need to be in place to avoid fish moving down the pipeline. The fish could be fine moving down the pipeline to deep water, or there could be issues. The fish could also become stranded in the pipeline which could be a concern. Heavily contaminated streams however would already significantly damage any fish already in the stream.
The issue of directing flows down a pipeline and potentially slopping flow in the creek could be a problem as well, especially if fish are present. Water from the lake or reservoir may need to be pumped up to the intake area to compensate for any stream losses. This would depend on the distance of the intake valve from the lake.
An intake system would be required to direct stream flows into the pipeline. A small dam or even a head pond 24 may be required to produce sufficient head to move enough water down the pipeline.
The surface water on a reservoir or lake would be circulating and mixing much more than water at deeper levels. Contaminated water entering at the surface will be thoroughly and quickly mixed with the existing lake water.
Water at greater depths would be relatively static and less subject to constant circulating and mixing. Any contaminated water that is directed down to the lower levels of the lake and dispersed carefully should remain in a relatively small and restricted area. The slow movement of the contaminated water would minimize any mixing with existing water. Contaminated stream flows may be only a very infrequent event and the actual volume may be quite small. Rather than mixing and contaminating the entire lake the silty water would remain in a small area in an almost static position. This is the ideal location for the contaminated water to be located to allow it to settle quickly with minimal mixing.
High-density polyethylene pipelines are often floated out into water bodies and sunk to the bottom to be used as effluent disposal systems. Concrete weights are often installed at the ends to ensure the pipeline docs not move. Openings at the ends are installed to allow the effluent to discharge. Concrete and steel pipelines can also be utilized as effluent discharge pipes.
Effluent pipelines are generally located to encourage rapid dispersal and dilution of the effluent. The best location is usually in a fairly rapidly moving water body to ensure mixing and dilution. The effluent is generally encouraged to mix and dilute with the surrounding water because this promotes breakdown and environmental treatment of the effluent.
The intention of the proposed silt system differs from a conventional effluent system because the contaminated water is discharged in a manner which minimizes any mixing and movement. The best way to treat the sediment laden discharge is to contain it to a small area and avoid mixing and excessive movement.
Silty water can contain fine suspended particles which settle out slowly, but it can also contain heavier particles which settle quickly. Potential silting and clogging of the discharge pipeline would have to be considered. A flushing process may need to be included in the design to overcome such silting and clogging.
Environmental issues tend to be reduced in deep water locations. Fish and vegetation is a less significant factor in deeper water. Often there is very little vegetation or fish. Discharge of contaminated silty water is ideally located in deep static locations.
Any debris located on the bottom of water bodies would need to be considered when placing a pipeline on the bottom.
The actual source of suspended particles can be located a distance from the actual main water body. A relatively small source can contaminate a larger stream well before it enters the lake or reservoir. In some situations, it may be easier to locate the actual source of the main contamination and potentially pipe that water to the lake even if it is a considerable distance. This much smaller flow from the contamination source can be piped down to the lake bottom, rather than piping the much larger stream. Each situation would be different and would need individual assessment.
Water temperature concerns may be a factor in some situations. Stream flows may be warmer or colder than the water located at the lake bottom. There may be fisheries concerns with moving surface water to the bottom. In addition, there may be other environmental factors to consider when moving surface flows to deep water locations. In some cases, it may be important to minimize flows to the lake bottom to reduce any of these impacts.
There are other situations where this system may be helpful, including, among others, mine tailing flows. Mine tailing flows are often treated and then transitioned through various settlement ponds before being discharged to water bodies. While these flows are not released until they reach acceptable levels they can still impact water bodies over time. If these flows can inexpensively be piped down to deep water locations and settle out over time this could greatly reduce the impacts for minimal cost.
For a mine tailings application, the contaminated water would need to be discharged over a distance to minimize movement and mixing. The design would need to consider the most effective method of containing the water while minimizing movement and mixing. It would have to be discharged over a large enough area to allow for years of operation. Buildup of sediment in the pipeline would need to be considered.
Mine tailings sediment is generally controlled with settlement ponds of various sizes. The sediment size determines how long it takes for material to settle out. Fine suspended sediments can take long periods of time to settle out. Larger sediments settle out quicker.
The proposed system essentially utilizes large parts of lakes or reservoirs as settlement ponds or areas. Deep locations in the reservoirs are often essentially static. The water does not circulate or mix with surrounding areas.
Creeks and streams generally carry both large and small sediments as part of their normal function. Boulders, rock, gravel and fine sediments are all carried by streams.
Larger particles generally settle out quickly. It is the fine suspended particles which create the longer term problems. There is no benefit to the larger particles entering the proposed pipeline system running to the lake bottom. The coarser heavier particles should be removed before entering the pipeline. The intake system would need to allow for this.
A conventional hydro penstock system generally considers sediments in the design. Coarse sediments and debris is screened or settled out before entering a penstock. A hydro system can handle some sediment because the high water flow will move out any debris and sediment.
In the proposed system, the water flow at dispersal would by design be much slower. The potential for sediment build up is greater and would need to be considered.
The intention of the pipeline outfall system is to dispense the sediment laden water over a given area determined by the design.
Various factors will determine how the outfall system should be designed.
Ideally the sediment should be spread out and not concentrated in a small area. However, the sediment should still be contained in an area of static water. It should not be allowed to circulate into the greater water body and risk contamination of larger areas.
The character of the water body and how the water circulates would need to be evaluated to determine the design of the system. Reservoirs and lakes vary considerably in their size, shape and water flows circulation. The character of the static or slow moving areas would also need to be evaluated.
The system should also move the water with sufficient volume to constantly flush the sediment from the pipes. It should flush the pipes without creating too much velocity and thereby too much mixing with the surrounding water.
The design of the pipeline would be a factor in how the water is dispensed. The pipe size and slope would impact the flow characteristics. The pipeline may need to consist of various sizes to modify the flow rates as the water is dispensed at various locations.
The dispersal pipe openings would likely vary in size and location on the pipeline to optimize the distribution of the water.
The purpose of the intake system is to direct the creek flows into the pipeline only when the water contains excessive sediment. The intake must be structured such that the water is forced down the pipeline rather than overflowing around the pipe. An overflow system would however always be required in the case when the creek flows exceed normal high flow levels. This would be designed to happen only every few years.
A sediment meter and directional valve would be required to direct the creek flows into the pipeline only when the sediment levels reach a certain level. If the sediment levels are below an acceptable level the water would flow down the normal creek route to the lake or reservoir.
The directional valve would be constructed such that the creek would function normally when flows are clean. There would be minimal impacts to habit and water quality.
The intake would be designed to screen out larger granular sediments and debris.
The intake system may need to allow for fish controls as well. Conventional hydro intake structures must account for any fish impacts.
When creek flows are redirected into the pipeline the creek flow below the intake will be disrupted. This is similar to some hydro projects and strict guidelines are required to manage this. A hydro project is required to maintain a minimum flow in a creek at all times. This depends on the existence of any fish.
Water from the reservoir or lake may need to be pumped up to the intake to account for the lost creek flows. Other solutions are also possible.
Alternatively, some sediment laden water could be allowed to remain in the creek to support any fish. This would contaminate the lake with some sediment but at a much lower level.
The location of the intake must also be considered. Ideally it should be relatively close to the lake to reduce the pipeline length. It also needs to function effectively. Moving the intake upstream may allow it to be less expensive or operate more effectively.
There is also the possibility that a smaller minor stream is the main contributor of sediment. This stream may be much farther upstream where it enters the main stream. It may be cost effective to construct a much smaller intake on this minor stream and install o longer but smaller pipeline down to the lake.
Each location would have different characteristics and require alternative designs and solutions.
Modem hydro intake systems are generally automated, especially when the intakes are in isolated locations. The proposed system could also be automated to function remotely. The system could be monitored and operated remotely to handle the current and expected stream and reservoir conditions.
As the system operated and monitoring continued the actual function of the system could be refined to improve efficiency. The reservoir water conditions could be monitored under various system scenarios to further refine efficiency.
The present invention offers a very effective and low cost way to deal with sediment in lakes and reservoirs. It may also prove to be useful for the treatment of other water contamination concerns.
Each part of the system could be refined to operate more effectively. The character of the sediment and how it is handled could be refined.
The present invention may be used for industrial discharge solutions. Many locations in the world discharge contaminants into water bodies with little regard for how it disseminates. If an inexpensive system to discharge it to deep water locations is available, it would be an improvement. Even advanced countries only treat industrial output water to a certain level, then discharge it. That treated discharge would be better to be discharged to deep water locations to continue to biodegrade.
The present invention may be used for storm water dispersal. Even highly advanced cities around the world often discharge storm water runoff directly into water ways. It is deemed as a low risk and is most easily and cost effectively dealt with by direct dumping into water bodies. Storm water, while deemed a low risk, still contains significant contaminants. Dumping it into the main water body will lead to mixing and widespread contamination. Discharging it to deep locations will reduce impacts to the main water bodies. Contaminants in large water bodies will eventually settle to the bottom, but it will take long periods because oceans are in constant circulation and mixing which slows down the settlement process. Contaminants discharged to deep locations will settle out much more quickly.
The present invention may also be used for mine tailings discharge. Mine discharge water is generally treated and then directed through various settlement ponds before being returned to the normal stream or river system. The water is treated and/or settles out until it reaches acceptable levels. Over time however the discharge still can have impacts on large water bodies. If the discharge however was directed to the lake bottom to settle further over time, it would impact the lake much less.
In prior art approaches, mine tailings in some cases were discharged directly to water bodies with minimal treatment, depending on the type of mine. Some mines in Canada sent tailings discharge into lakes as recently as the last 20 years. Mine tailings are generally contained in tailings ponds for eternity in some eases. However, these ponds can be very unstable, especially in earthquake conditions.
There are numerous places around the world where mine tailings continue to be discharged directly into water bodies. Under normal conditions these tailings would contaminate the entire water body until they settled out. If tailings were continually discharged the lakes would never recover.
If tailings were deposited to lake bottoms directly and allowed to settle relatively quickly in undisturbed environments, contamination of the lakes would be dramatically reduced. If it could be accomplished inexpensively the chances of its implementation would be increased. Deposition and settlement of tailings in deep lakes would be performed similarly to the proposed system of dealing with sediment laden water.
High quality water can be highly beneficial as drinking water. However, it can be valuable for industry as well. Water sources which have minimal sediment content are prized for various industrial processes. Link Lake in Ocean Falls was one of the main reasons the Ocean Falls Pulp and Paper Business was located there for many years. Ocean Falls was one of the top producing mills in BC for many years. The quality of the water in Link Lake is still well known to industry as a high-quality water source, hence the reason for locating an on-land fish rearing facility in that location. Various other businesses have considered locating to Ocean Falls to take advantage of the water source. Link Lake is so valuable because the lake is very long which allows abundant time for the sediment to settle out.
The proposed system includes a stream intake structure which is connected to a pipeline which runs out into the lake and is situated on the lake bottom. Dispersal openings at the end of the pipeline distribute the contaminated water to the static bottom layer of water. The contaminated water remains in the static bottom layer of lake water and settles out rather than mixing with the main reservoir water.
The intake structure is located on the contaminated stream relatively close to the lake. The intake directs the stream flow into the pipeline. The water is directed into the pipeline only when it is contaminated. Clean stream flows are allowed to follow the normal stream route.
The intake structure includes a sediment meter and directional valve. The flow is directed into the pipeline only when contaminated above a certain level as determined by the sediment meter. Otherwise the flow follows the normal stream route to the lake.
The intake structure includes fish and debris control devices which minimize any fish or large debris particles from entering the pipeline. The intake system which may include a head pond, limits the amount of larger size heavy granular rocks from entering the pipeline.
The pipeline is sized to handle the normal stream flows. An overflow system would be included to handle the eventuality of an excessive stream flow which exceeds the pipeline capacity.
The pipeline carries the contaminated water down to the bottom of the lake or reservoir where water is generally static or very slow moving.
The pipeline has distribution openings close to the end. The openings distribute the silty water over a given design discharge area. The size, spacing and orientation of the openings will vary with the design criteria. The intention is to disperse the silty water over an area while ensuring the material remains within the area of relatively static water. The sediment laden water once distributed should remain relatively static and should settle out quickly.
The pipeline may be subject to some buildup of silt over time. The velocity of the water in the system should be designed to distribute the water while minimizing the silt buildup within the pipeline. Alternatively, a flushing system may need to be incorporated to ensure sediment buildup can be removed on a regular basis.
The pipeline distribution system should be located as much as possible in an area of static or slow moving water. This will facilitate more rapid settlement of the sediment. It will also minimize any circulation and mixing with the surrounding water. A conventional effluent discharge system encourages pipeline discharges in areas of rapidly moving water to encourage rapid mixing and dilution of the effluent. This facilitates dissemination over a larger area and increased environmental biodegradation. This is directly opposite of the intention of the sediment distribution system.
A conventional effluence discharge system would want to disperse the effluent rapidly to discourage any blockages or backups in the system. The velocity of the discharge would be designed to disperse and mix with the surrounding water as much as possible. The sediment control proposed system would be designed to discharge the silty water only enough to distribute it over a limited area. The velocity would be kept as slow as possible to minimize dissemination and mixing with surrounding water. The velocity would be just sufficient to disseminate the material and to minimize settlement of the sediment.
The intake system would include an automated sediment meter to monitor and control the direction of the stream flow. When the sediment reached a certain level, the meter would initiate the directional valve. The valve would redirect the stream flow into the pipeline. Conventional effluent systems do not have this type of directional control system.
The discharge system would be located as much as possible in an area where the water is static or slow moving. The most efficient way to treat sediment laden water is to maintain it in a static or very slow moving location for as long as possible. This is the best way to promote sediment settlement. Alternatively, the best way to promote treatment of conventional effluent is to encourage wide distribution and continual mixing.
Sediment laden water should be directed as deep in a reservoir or lake as possible. Sediment in any conventional large water body will generally settle to the bottom over time. By dispensing the sediment water directly to the bottom or close to the bottom will just facilitate the normal process that occurs in all water bodies. It will also avoid wide spread contamination of the entire water body and the longer term settlement process which occurs as a result. Water at the bottom of a reservoir is generally more static or slow moving which further encourages settlement. Alternatively, a conventional effluent pipeline discharges into water which is rapidly moving but not necessarily deep. The effluent because of its nature is discharged at a minimal depth, but just to avoid any surface impacts. The intention is to place the material at a minimal depth within rapidly moving water to ensure rapid mixing, and dissemination over a large area. Placing the effluent too deeply will likely mean it is in slower moving water with less chance of mixing and dissemination.
Sediment laden water placed at lake bottoms will have lower environmental impacts. At deeper elevations the habitat and wildlife will be much less, and the sediment will have much less impact. Conventional effluent treatment is best if it is located and disseminated in an area of high habitat and wildlife. This will encourage the more rapid treatment and biological breakdown of the effluent.
Sediment laden water is managed most effectively by being contained in a limited area and allowed to settle with as little disturbance as possible. Conventional effluent is treated more effectively by mixing, dilution and dissemination as much as possible. The more widely it is disseminated the more it will be exposed to biological breakdown mechanisms. The placement and dispersal systems have radically different approaches and intentions when placing sediment laden water versus effluent.
Conventional methods to control sediment laden water is to avoid any contact with larger water bodies. The preferred approach is to isolate the water in settlement ponds or process it through sediment removal systems. Generally, once the contaminated water is in contact with a large water body, mixing and dispersal is inevitable and removal of the sediment becomes significantly more complicated. Dispensing the sediment laden water into a large water body at depth in static locations is a drastically different approach than conventional systems. The critical part of the approach is to ensure the water is dispensed in a deep water location which is static and to minimize mixing with surrounding water. This essentially places the material into a confined settlement area within the larger water body.
The effectiveness of the system depends on how easily the contaminated streams can be isolated from the majority of flow into a water body. If a few small streams arc involved and easily be contained the system could be very effective. If the contaminated streams are a large portion of the lake inflow, then the treatment system may be less effective.
The size of the water body relative to the info volumes is also an important factor. The larger the volume of static and deep water there is relative to the contaminated inflow volume will determine the effectiveness of the system. The system will vary in effectiveness with each reservoir scenario.
According to an alternate embodiment of the present invention, the intake system and pipeline structure may be a temporary structure to handle temporary contaminated water situations.
According to another embodiment, the discharge pipe may float out on the top of a reservoir to a selected location and extend vertically downward to the bottom of the water body with a dispersal pipe located on the bottom. This embodiment may be moved to discharge in various locations.
As has been indicated, there are numerous potential applications for the present invention where contaminated water is best placed at lower levels of the water body in static locations where it will not mix with the main water body.
For example, the system of the present invention may be used for improved mine tailing or industrial settlement pond operation. Prior art settlement ponds operate by adding new contaminated flows directly into the main water body, resulting in constant recirculation and mixing of the entire water body, thereby drastically reducing the efficiency of the settlement process. According to the method of the present invention, new contaminated flows may be placed slowly to the bottom of the settlement pond without disrupting and mixing with the main waterbody, resulting in much quicker settlement. The capacity of mining settlement ponds can limit the productivity of a mining operation. Settlement ponds and disposing of the runoff water can be an enormous cost and limiting factor to productivity and profitability. Improving settlement pond efficiency can improve the operation. Disposing of some of the run-off water earlier by deep static discharge can also improve settlement pond efficiency. Silt settlement pond management would also be improved in the same maimer as industrial ponds. If silt laden water is slowly distributed to the bottom of settlement ponds without mixing with the main water body, then settlement will result much quicker.
According to one embodiment, mine tailings may be placed into a lake or ocean deep static zone, rather than into a settlement pond if the tailings may be safely placed in such location. In some cases, deep static zone discharge of tailings will be safer that in a settlement pond which may be subject to earthquake failure.
Another application may be water which has become contaminated or silty from construction operations and which is to be discharged from a work site to a water body. For some industrial discharges such as heated water or some chemical or radioactive contaminants, the discharge may be best handled by deep static discharge into a water body according to the method of the present invention. Similarly, agricultural discharges such as water bearing high levels of fertilizer or organic contaminants may be appropriate for deep static discharge into water bodies.
It would be advantageous to direct community storm drains using the system of the present invention to deep, static locations within water bodies.
In an industrial context, as well as providing a solution for contaminated discharge, the present invention can improve the quality of source water for industry by reducing the silt contamination of water bodies used as industrial water sources. With respect to fisheries, fish habitat would be improved through a decrease in siltation and contamination.
It is to be understood that any low turbulence zone within a water body may be appropriate for settlement according to the present invention, including oceans.
It will be appreciated by those skilled in the art that other variations of the preferred embodiment may also be practiced without departing from the scope of the invention.
Claims
1. A sediment control system for a silt contaminated source, comprising:
- a. an intake system for reversibly diverting flow from the contaminated source to a pipeline structure having proximal and distal ends, the pipeline extending from the intake system to a low turbulence zone within a water body; wherein the distal end of the pipeline further comprises a plurality of discharge outlets selectively spaced to minimize mixing of the contaminated source flow with the water body.
2. The sediment control system of claim 1, wherein the pipeline structure comprises a pipeline submerged along the bottom of a water body, the system further comprising submersion means for maintaining the distal end of the pipeline near the bottom of the water reservoir.
3. The sediment control system of claim 2 wherein the submersion means comprises one or more concrete weights distributed along the distal end of the pipeline.
4. The sediment control system of claim 1, wherein the pipeline structure includes a floating horizontal pipeline portion extending from the edge of the water body to a position vertically above the low turbulence zone, and a submerged vertical pipeline portion extending from the floating portion to the discharge outlets at the bottom of the water body.
5. The sediment control system of claim 1, wherein the contaminated source is selected from the group of contaminated sources comprising a stream, an industrial discharge, a construction site siltation settlement pond, a community storm drain, and a mine tailings source.
6. The sediment control system of claim 1, wherein the water body is selected from the group of water bodies comprising a lake, an ocean, a settlement pond, and a water reservoir.
7. The sediment control system of claim 1, further comprising means for replenishing the watercourse.
8. The sediment control system of claim 7, wherein the means for replenishing the watercourse comprise a water pumping system to move water from the water reservoir to the watercourse downstream of the intake system.
9. The sediment control system of claim 1, wherein the intake system is selected from the group of intake systems comprising a dam and a head pond.
10. The sediment control system of claim 1, wherein the intake system further comprises a flow control system.
11. The sediment control system of claim 1, wherein the intake system further comprises a sediment monitoring system.
12. The sediment control system of claim 1, wherein the intake system further comprises a flow directional control valve.
13. The sediment control system of claim 1, wherein the intake system further comprises a screen for removing large granular particles and debris.
14. The sediment control system of claim 1, further comprising a fish diversion structure to allow fish to bypass the intake system.
15. The sediment control system of claim 1, further comprising an overflow management system.
16. The sediment control means of claim 1, further comprising flushing means for clearing residual sediment from the pipeline.
17. A method of controlling sediment in a water body fed by one or more contaminated sources, comprising the following steps:
- a. diverting a portion of the silt-contaminated water of at least one of the silt-contaminated streams into an intake system:
- b. transferring the silt-contaminated flow into a pipeline extending from the intake system to a low turbulence zone within a water body; and
- c. discharging the silt-contaminated flow through a plurality of selectively spaced discharge openings in the distal end of the pipeline.
18. The method of claim 17, wherein the contaminated source is selected from the group of contaminated sources comprising a stream, an industrial discharge, a construction site siltation settlement pond, a community storm drain, and a mine tailings source.
19. The method of claim 17, wherein the water body is selected from the group of water bodies comprising a lake, an ocean, a settlement pond, and a water reservoir.
20. The method of claim 17, further comprising the additional initial steps of:
- a. monitoring the sediment levels in the one or more contaminated sources; and
- b. adjusting a directional flow control valve to select the portion of the contaminated water to be diverted into the intake system.
21. The method of claim 17, further comprising the additional step of replenishing the contaminated sources with water piped from the water body.
22. Use of the sediment control system of claim 1 for reducing silt contamination in a stream.
23. Use of the sediment control system of claim 1 for safely discharging contaminated industrial sources.
24. Use of the sediment control system of claim 1 for storm drain discharge.
25. Use of the sediment control system of claim 1 for industrial effluent settlement.
26. Use of the sediment control system of claim 1 for mine tailings settlement.
Type: Application
Filed: Jun 18, 2018
Publication Date: Jun 4, 2020
Inventor: Ian FARQUHARSON (Courtenay, BC)
Application Number: 16/624,015
