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[0001]    This invention relates generally to canal and levee devices, and specifically to structural reinforcement of canal and levee devices. 
       STATEMENT REGARDING FEDERALLY FUNDED RESEARCH 
       [0002]    This invention was not made under contract with an agency of the US Government, nor by any agency of the US Government. 
       BACKGROUND OF THE INVENTION 
       [0003]    The strength and durability of canals and levees in the US has never been more important than at the present time, as the continual physical development of the nation brings ever larger numbers of individuals and ever more expensive physical investments into areas prone to damage should a levee or canal break. 
         [0004]    Obviously, the devastation in the aftermath of Hurricane Katrina and the collapse of the levees protecting New Orleans and other parts of Southern Louisiana from flooding of the waters of Lake Pontchartrain is the first example of this which comes to mind: at least 1836 people lost their lives. It has been estimated that if the federal government undertook the task of rebuilding New Orleans, it would cost between 80 and 100 billion US dollars. 
         [0005]    But the problem is potentially much more widespread than that. There are so many aqueducts, ditches, canals and levees in the United States that numbering them may be impossible. 
         [0006]    The single largest and most expensive aqueduct system built in the US, the Central Arizona Project, has a backbone which covers 336 miles (˜540 km) from Lake Havasu to the Tucson area, with vast amounts of concrete and berming used to try and provide long term stability to the walls of the aqueduct. 
         [0007]    Numerous other smaller US canals and aqueducts exist, for example, the California Aqueduct is 444 miles (˜700 km) long. One (partial) list of US irrigation aqueducts includes the All-American Canal, Coachella Canal, the Colorado River Aqueduct, the Contra Costa Canal, the Hillsboro Canal, the Los Angeles Aqueduct and storm drainage system often seen in movies, the Miami Canal, the famous St. Lucie Canal crossing Florida, the Tamiami Canal, the El Paso Canal, the Franklin Canal, the American Canal, the largely abandoned Erie Canal, and the Riverside Canal, however, many more irrigation canals exist, and a large number of transportation canals also exist as well. Most of these are “dug in” and thus not in immediate danger of collapse, but nonetheless large numbers of levees and canals have miles of unsupported “levee” style sides. The Army Corps of Engineers inspects over 2,000 levees nationwide, some of them miles long. The total number of levees in the US may be unknown, but the Corps estimates that up to 146 of these levees may present flood risks in danger of failure. In the end, many of these levees and many more will need to be made stronger. 
         [0008]    Thus even if irrigation ditches and the like (functionally smaller canals and smaller levees) are not counted, the problem of levee strength is a gigantic one. 
         [0009]    It would be preferable to provide some method of increasing the strength of levee walls at low cost, without berming or other large scale engineering projects. 
         [0010]    Various systems exist of internal bracing. 
         [0011]    U.S. Pat. No. 4,596,491 to Dietzler on Jun. 24 th , 1986 teaches small bore plastic pipes having internal reinforcement, and since it involves small pipes, it cannot be considered relevant to levees large enough to hold supertanker ships. The internal reinforcement is primarily designed to withstand external forces rather than hydrostatic or hydrodynamic forces. 
         [0012]    U.S. Pat. No. 6,202,305 to Bracque et al on Mar. 20 th , 2001 teaches a large air distillation column with external bracing around a cylindrical central fluid unit, which suffers from a great structural variance from both prior art levees and also from the present invention. 
         [0013]    U.S. Pat. No. 4,315,099 issued to Gerardot et al on Feb. 9 th , 1982 teaches yet another pipe or cable type device, again not relevant to ocean or river levees. 
         [0014]    Finally WO 2004/056677 to Ki-jun Kim and published Jul. 8 th , 2004, teaches a portable cubical holding tank with internal supports which run in diagonal directions between small square plates of the skin of the tank. It does not teach a design allowing waterborne traffic, does not teach perpendicular internal supports and relates to water storage, not to waterways or shorelines. 
       SUMMARY OF THE INVENTION 
       [0015]    General Summary 
         [0016]    The present invention teaches that a levee, canal or aqueduct wall may be internally supported by tensional members such as cables, bars, chains, carbon composites and the like which stretch across the width of the waterway. By this means, outward hydrostatic and/or hydrodynamic force of water onto the wall of the waterway or shoreline levee is matched by a tensional force anchored on the opposite wall. 
         [0017]    In embodiments the tensional members may leave a space between the topmost member and the water level, so as to allow for passage of water vessels above the cables, in waterways, lakes or oceans in which traffic occurs. 
         [0018]    Vertical or horizontal struts or individual anchors attached to the ends of the cables may be positioned within, partially within or outside of the walls. Struts may extend so as to provide anchoring to several tensional members, and in addition act to spread the tensional forces of the member onto a larger area of the wall. 
         [0019]    Due to the strength of the device, the waterway wall/shoreline levee may even be constructed at an angle to the vertical, even leaning outwards, advantageous in that it allows a wider waterway for traffic but may be narrower at the bottom as necessary for local conditions. 
         [0020]    External guying tensional members may be anchored and may connect to the wall or the internal tensional members to provide tensional support to prevent motion in the inward direction, especially collapse, either temporarily (such as during construction) or permanently. These anchoring guying tensional members would also provide stability in situations where hydrostatic and/or hydrodynamic pressure may be greater on one of the 2 walls or the waterway, such as a curve or change in course of the waterway. 
         [0021]    Unlike tensional members for placid water storage devices, such as water tanks, the tensional members of the waterways of the invention must be anchored, strong enough, and dimensioned and configured to resist the side pressure of moving water. 
         [0022]    Summary in Reference to Claims 
         [0023]    It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide a waterway comprising: 
         [0024]    first and second parallel facing sidewalls having a first thickness, two proximally open sides and a bottom, thereby defining therebetween an extended longitudinal water course through which water may flow for a first distance; 
         [0025]    at least one tensional member firmly secured to and bearing load in tension from both sidewalls. 
         [0026]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising: 
         [0027]    two ends of the tensional member; and 
         [0028]    at least one anchor firmly securing at least one end of the tensional member to at least one sidewall. 
         [0029]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, wherein the tensional member further comprises: 
         [0030]    a cable. 
         [0031]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising: 
         [0032]    a second tensional member firmly secured to and bearing load in tension from both sidewalls at a second distance from the first tensional member. 
         [0033]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
       a vertical navigation clearance distance, the vertical navigation clearance distance greater than the second distance.       
 
         [0035]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising: 
         [0036]    two ends of the perpendicular tensional member; and 
         [0037]    at least one horizontal anchor strut firmly securing at least one end of the tensional member to at least one sidewall. 
         [0038]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising: 
         [0039]    two ends of the perpendicular tensional member; and 
         [0040]    at least one vertical anchor strut firmly securing at least one end of the tensional member to at least one sidewall. 
         [0041]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising: 
         [0042]    at least one guying tensional member external to the water course, the at least one guying tensional member having a first end secured to the first wall. 
         [0043]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising: 
         [0044]    a second end of the at least one guying tensional member, the second end secured to an anchor located separate from the first wall. 
         [0045]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising: 
         [0046]    two ends of the tensional member; and 
         [0047]    at least one anchor firmly securing at least one end of the tensional member to at least one sidewall, the anchor having a U-shaped body, the U-shaped body having an internal diameter, the internal diameter substantially equal to the first thickness. 
         [0048]    It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway wherein the second distance between the first and second tensional members further comprises: 
         [0049]    an intermediate navigation clearance distance. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0050]      FIG. 1  is a cross-sectional view of a first embodiment of the device showing a simple embodiment. 
           [0051]      FIG. 2  is a cross-sectional diagram of a second embodiment of the device, having a space allowing navigation above the tensional members. 
           [0052]      FIG. 3  is a cross-sectional diagram of a third embodiment of the device, showing vertical outside struts. 
           [0053]      FIG. 4  is a cross-sectional diagram of a fourth embodiment of the device showing horizontal longitudinal outside struts. 
           [0054]      FIG. 5  is a cross-sectional diagram of a fifth embodiment of the invention showing that it makes it more practical to make levees or canals with sides sloping outward but without earthen or other support. 
           [0055]      FIG. 6  is a cross-sectional diagram of a sixth embodiment of the invention showing that external guying tensional members may be used. 
           [0056]      FIG. 7  is a cross-sectional diagram of a seventh embodiment of the invention showing that tensioning members and walls of the levees may extend into and under the ground beneath the waterway. 
           [0057]      FIG. 8  is a cross-sectional diagram of an eighth embodiment of the invention showing that elevated guying tensional members may be used. 
           [0058]      FIG. 9  is a cross-sectional diagram of a ninth embodiment of the invention showing that a sleeved retrofit may be used within the scope of the invention. 
           [0059]      FIG. 10  is a top planform view of a section of waterway seen from above, showing alternative arrangements of the tensional members. 
           [0060]      FIG. 11  is a cross-sectional diagram of an tenth embodiment of the invention showing that only elevated guying tensional members may be used. 
           [0000]    
         
           
                 
               
                 
                 
                 
               
             
                 
                     
                 
                 
                   INDEX TO REFERENCE NUMERALS 
                 
                 
                     
                 
               
               
                 
                     
                 
               
            
             
                 
                     
                   Levee/canal 
                   100 
                 
                 
                     
                   First side wall 
                   102 
                 
                 
                     
                   Second side wall 
                   104 
                 
                 
                     
                   Open bottom 
                   106 
                 
                 
                     
                   Foundation/berm 
                   108 
                 
                 
                     
                   Tensional members 
                   110a-i 
                 
                 
                     
                   Tensional tightening mechanism 
                   111a, 111b 
                 
                 
                     
                   Bottom 
                   206 
                 
                 
                     
                   Tensional members 
                   210a-d 
                 
                 
                     
                   Vertical navigation clearance 
                   212 
                 
                 
                     
                   First side wall 
                   302 
                 
                 
                     
                   Second side wall 
                   304 
                 
                 
                     
                   Open bottom 
                   306 
                 
                 
                     
                   Foundation/berm 
                   308 
                 
                 
                     
                   Tensional member 
                   310a 
                 
                 
                     
                   Vertical strut 
                   312 
                 
                 
                     
                   Tensional members 
                   410a-d 
                 
                 
                     
                   Horizontal longitudinal struts 
                   416a-d 
                 
                 
                     
                   First eccentric side wall 
                   502 
                 
                 
                     
                   Second eccentric side wall 
                   504 
                 
                 
                     
                   Differing tensional members 
                   510a-d 
                 
                 
                     
                   Side wall 
                   604 
                 
                 
                     
                   Tensional members 
                   610a-d 
                 
                 
                     
                   Guying tensional members 
                   618a-d 
                 
                 
                     
                   Anchor 
                   620 
                 
                 
                     
                   First sidewall 
                   702 
                 
                 
                     
                   Second sidewall 
                   704 
                 
                 
                     
                   Berm 
                   708 
                 
                 
                     
                   First tensional member 
                   710a 
                 
                 
                     
                   First sidewall 
                   802 
                 
                 
                     
                   Tensional member 
                    810d 
                 
                 
                     
                   Sidewall 
                   902 
                 
                 
                     
                   Tensional member 
                    910d 
                 
                 
                     
                   Sleeve 
                   922 
                 
                 
                     
                   Opening/attachment 
                   924 
                 
                 
                     
                   Sidewall 
                   1004  
                 
                 
                     
                   First tensional member 
                   1010d 
                 
                 
                     
                   Second tensional member 
                   1026  
                 
                 
                     
                   Third tensional member 
                   1028  
                 
                 
                     
                   Anchor 
                   1030  
                 
                 
                     
                   First sidewall 
                   1102  
                 
                 
                     
                   Tensional member 
                   1110d 
                 
                 
                     
                     
                 
               
            
           
         
       
       
    
    
     DETAILED DESCRIPTION 
       [0061]      FIG. 1  is a cross-sectional view of a first embodiment of the device showing a simple embodiment. Levee/canal  100  may be a small “ditch” (irrigation canal mere inches or feet in width) or it may be wide enough to allow supertanker ships. In any case, it may extend for a first distance which may be as much as many miles in length or it may be merely blocks in length, as some of the levees are in the city of New Orleans. 
         [0062]    First side wall  102  and second side wall  104  act to contain water within the confines of the waterway. The side walls  102 ,  104  may be constructed of reinforced concrete, concrete, metal, masonry, carbon composites, wood, and combinations thereof and have a first thickness suitable to containing such water given the additional reinforcement provided by the invention. In particular, in original equipment installations, the thickness of the walls may be less than the thickness of a side wall required to withstand the hydrostatic and hydrodynamic forces of the waterway unaided. The side walls  102 ,  104  may have foundations, or may have small earthen berms  108  as foundations as shown, or may sit atop substantial berms for additional height, or may realistically extend into the ground for a certain depth, so as to act as their own foundations. 
         [0063]    Open bottom  106  may exist in certain embodiments such as irrigation channels or the like. 
         [0064]    Side walls  102 ,  104  and bottom  106  define therebetween the extended/elongated water course of the waterway, through which water may flow from end to end of the waterway for the distance of the waterway, as two locally or proximally open “sides” of the waterway allow the waterway to be a waterway for moving water or vehicular traffic rather than a storage tank having four enclosed sides. That is, the device of the invention has two side walls and two openings (the entire length of the waterway) which allow water flow therethrough. The total length of the waterway may have one or two “ends” at some distant location, but is nonetheless locally open on two sides at any point other than the end or ends and thus the proximal sides are “open” for the entire intermediate length of the waterway so as to allow motion of water or ships through the waterway. 
         [0065]    Foundation/berm  108  may be constructed of rammed earth or the like, or may be constructed of concrete or the like. 
         [0066]    Tensional members  110   a - i  may be present in such numbers are as necessary to support the expected maximum load of water. In embodiments, at least one perpendicular tensional member is used, secured to each facing sidewall and extending across the width of the waterway between the sidewalls under tension, so as to provide tensional support to each wall and in effect, to “balance” the forces generated by water on one wall with the forces generated by water on the other wall. A first distance may separate two of the tensional members, which distance may be vertical or horizontal or a combination of both, and which distance may be different for different pairs of the members. 
         [0067]    Preferably the tensional members should be perpendicular to the length of the parallel side walls, as non-perpendicular tensional members will exert undesirable forces along the length of the side walls. However, in alternative embodiments other orientations may be used. 
         [0068]    Unlike tensional members for water storage devices with little or no water motion, the tensional members of the waterways of the invention must undergo lateral forces due to moving water (hydrodynamic forces) and thus are structurally more sturdy than tensional members for static water structures: this difference is termed “strong enough to resist lateral hydrodynamic forces” for purposes of this invention. The tensional member of the invention must also have stronger anchoring, and must dimensioned and configured to resist the side pressure of moving water. For example, the tensional members may have struts or anchors as discussed in regard to  FIG. 3  and other figures, and must be anchored into the strong, normally reinforced concrete walls of the waterway. The tensional members may also have hydrofoil cross shapes to aid in minimizing forces due to water flow or water motions (such as from passing vessels). Tensional tightening mechanisms  111   a ,  111   b  may be provided to maintain the tensional members under tension at all times or to tighten them as necessary periodically. It will be appreciated that unlike static water holding tanks, random variations in moving water of waterways will cause random variations in tension, which may be undesirable, and thus tightening mechanisms may be necessary. 
         [0069]    It may be seen that the device and apparatus of the invention may easily be retrofitted to an existing waterway wall or incorporated as original equipment in a newly constructed/reconstructed wall. In particular, the use of struts/anchors external to the wall is suited to retrofit applications. 
         [0070]    The device of the invention even allows creation of portable temporary waterways, since the waterway of the invention can be constructed with no berming nor concrete of any type, merely with large strong plates or panels joined at water-tight edges so as to make walls, with cables to support the walls. 
         [0071]    While the top of waterway is shown to be open, the waterway may of course be enclosed in alternative embodiments of the invention. 
         [0072]      FIG. 2  is a cross-sectional diagram of a second embodiment of the device, having a space allowing navigation above the tensional members. 
         [0073]    Bottom  206  may be a solid construction, much like the side walls. For example, the bottom  206  may be reinforced concrete or other materials used in the construction of the side wall, including portable panels. 
         [0074]    Tensional members  210   a - d  may be seen to be disposed with a fairly large vertical navigation clearance  212  between them and the maximum water level in the waterway. In the diagram, the tensional members  210   a - d  may be seen to be disposed closer to bottom  206  than to the top of the waterway side walls and/or the maximum water level (which may be either below the top of the waterway side walls or coterminous therewith). 
         [0075]      FIG. 3  shows water traffic using such a waterway, as long as the depth of water above the topmost tensional member exceeds the draft of the vessels using the waterway. 
         [0076]      FIG. 3  is also a cross-sectional diagram of a third embodiment of the device, showing vertical outside struts. First side wall  302  and second side wall  304  bear on them anchors which aid in securing the tensional members such as tensional member  310   a  to the side walls  302 ,  304 . The wall anchors also aid in transferring the load from a larger area of the wall to the tensional members, thus providing load distribution and allowing for thinner and thus more portable walls. 
         [0077]    Vertical strut  312  may be seen to be one such anchor, which in this variant embodiment extends vertically up the sides of the waterway walls. Such anchors may be disposed on the outside faces of the walls, or may be partially within the wall structure, or may even be entirely within the wall structure. Each strut  312  may meet more than one tensional member in a vertical direction. 
         [0078]    Open bottom  306  and foundation/berm  308  are as previously discussed in relation to  FIGS. 1 and 2 . 
         [0079]      FIG. 4  is a cross-sectional diagram of a fourth embodiment of the device showing horizontal longitudinal outside struts, the preferred embodiment and best mode contemplated for the invention. 
         [0080]    Tensional members  410   a - d  meet a plurality of horizontal longitudinal struts  416   a - d , which may extend along the length of the waterway (or at least a portion of the waterway length) or may be individual cable end anchors anchoring only one tensional member end. If the longitudinal struts are employed, then each strut may secure a number, even a large number, of cables disposed in a horizontal line. 
         [0081]    Note that in alternative embodiments, struts may extend in a diagonal direction and meet and secure several cable ends. 
         [0082]      FIG. 5  is a cross-sectional diagram of a fifth embodiment of the invention showing that the invention makes it more practical to make levees or canals with sides sloping outward but without earthen or other support. First eccentric side wall  502  and second eccentric side wall  504  may extend in directions not necessarily vertical, nor even mirror images of each other, if properly supported by differing tensional members  510   a - d , which may be seen to have differing lengths. Normally extensive berming is required to make an aqueduct or canal or levee wall safe in a non-vertical orientation, however, the present invention allows quick construction of a waterway even with sloping side walls  502  and/or  504 . Advantages of such slopes include the ability to allow the waterway to avoid ground level obstacles, allow creation of a smaller bottom and/or smaller “footprint”, and yet allow a wider waterway for increased water flow or wider waterborne traffic. 
         [0083]      FIG. 6  is a cross-sectional diagram of a sixth embodiment of the invention showing that external guying tensional members may be used. Side wall  604  has internal tensional members  610   a - d  and also has another set of secure attachments to guying tensional members  618   a - d  which are located external to the waterway. The secure attachments of the internal and external tensional members may be at the same place, functionally connecting the two sets of members, or the attachments may be at different places, or there may be single set of tensional members which extend through the side walls and are thus both external and internal to the waterway, and are also both external and internal to the side wall  604 . 
         [0084]    Anchor  620  may be of normal type for suspension cable anchoring, devices of the type are used in suspension bridge construction and similar applications. 
         [0085]    The width, size, length and material of the members may be different between external and internal or between members located at different locations, as seen in comparing the lower and upper external tensional members  618   a  and  618   d  of  FIG. 6 . 
         [0086]      FIG. 7  is a cross-sectional diagram of a seventh embodiment of the invention showing that tensioning members and walls of the levees may extend into and under the ground beneath the waterway. First sidewall  702  and second sidewall  704  may be seen to extend their feet or foundations down into or even through and below berm  708 . First tensional member  710   a  may be seen to be partially or wholly underground in such variations. 
         [0087]      FIG. 8  is a cross-sectional diagram of an eighth embodiment of the invention showing that elevated guying tensional members may be used. An intermediate navigation clearance distance is thus created allowing vehicular traffic to pass below some sets of cables, and also decreasing the water flow drag on the cables by reducing the number of cables underwater. 
         [0088]    First sidewall  802  may be seen to be tall enough to allow tensional member  810   d  to extend therefrom yet still be above the level of waterborne traffic. Posts, pillars and extensions of the sidewall and the like may be used to elevate the tensional members in variations of this. 
         [0089]      FIG. 9  is a cross-sectional diagram of a ninth embodiment of the invention showing that a sleeved retrofit may be used within the scope of the invention. 
         [0090]    Sidewall  902  may be an older sidewall not originally intended for use with the invention. Thus it may have a thickness greater than a sidewall originally designed for the invention, but may still be employed with the invention. Examples of the need for this include cases in which reassessment of the local environmental conditions indicate greater strength is called for, or in which the wall is degrading with age, found to be substandard and so on. 
         [0091]    Tensional member  910   d  may be attached to permanent anchors within or without the walls as previously shown, however, in this embodiment tensional member  910   d  is affixed to an anchor in the form of elongated U-shaped sleeve  922  having an open bottom which may be easily affixed over the top of the older wall. Opening/attachment  924  may have an internal diameter substantially equal to the thickness of the wall, that is, equal to or slightly greater than the thickness of the wall. An attachment on opening  924  may assist in securing sleeve  922  to wall  902  as well. 
         [0092]      FIG. 10  is a top planform view of a section of waterway seen from above, showing alternative arrangements of the tensional members. Sidewall  1004  may have first perpendicular tensional member  1010   d  but may instead or additionally have second tensional member  1026  set at a first angle to the perpendicular and third tensional member  1028  set at a second angle. 
         [0093]    Anchor  1030  may have multiple tensioning members affixed thereto, so as to allow side forces to be cancelled at the anchor point rather than in the wall. 
         [0094]      FIG. 11  is a cross-sectional diagram of an tenth embodiment of the invention showing that only elevated guying tensional members may be used. First sidewall  1102  has only elevated tensional members such as member  1110   d , and thus the vertical navigation area is below the members: this embodiment may be either original equipment or a retrofit. 
         [0095]    The disclosure is provided to allow practice of the invention by those skilled in the art without undue experimentation, including the best mode presently contemplated and the presently preferred embodiment. Nothing in this disclosure is to be taken to limit the scope of the invention, which is susceptible to numerous alterations, equivalents and substitutions without departing from the scope and spirit of the invention. The scope of the invention is to be understood from the appended claims.

Summary:
A levee, canal or aqueduct wall is internally supported by tensional members such as cables which stretch across the width of the waterway. In embodiments the tensional members may leave a space between the topmost member and the water level, so as to allow for passage of sea vessels above the cables. Vertical or horizontal struts or individual anchors attached to the ends of the cables may be positioned within, partially within or outside of the walls. Due to the strength of the device, the waterway wall may even be constructed at an angle to the vertical, even leaning outwards. External guying tensional members may be anchored and may connect to the wall or the internal tensional members to provide tensional support to prevent motion in the inward direction, either temporarily (such as during construction) or permanently.