Abstract:
A device prevents water from leaking into a manhole. The device includes a body having first and second portions that are integrally formed. The first portion extends along and above a periphery of the opening of the manhole and the second portion extends upwardly from the first portion and provides access to the opening of the manhole. Preferably, the first portion includes a downwardly extending lip disposed along an outer vertical surface of the manhole. In addition, a cap is positionable on the second portion to prevent water entering the manhole from the manhole&#39;s opening.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
   This application claims the benefit of U.S. Provisional Application No. 60/318,233 filed on Sep. 7, 2001. 
   BACKGROUND OF THE INVENTION 
   The present invention relates to an apparatus for insertion into a manhole. More particularly, the present invention relates to an apparatus which is inserted into a manhole to prevent water leakage into the manhole. 
   Most cities and municipalities typically have two separate sewer systems, a sanitary sewer system and a storm water sewer system. The sanitary sewer system is designed to accept water that is discharged from homes and business including, but not limited to, water that is used in the toilet, cooking, bathing and washing clothes. All of the water that enters the sanitary sewer system is treated in a waste water treatment facility prior to being discharged into the environment. 
   The storm water sewer system is designed to accept large quantities of water from rainfall and melting snow. Typically, the water entering the storm water sewer is clean and not needing treatment. Therefore, the water transferred through the storm water sewer system is discharged directly into the environment without being treated in the waste water treatment facility. 
   Because all the water entering the sanitary sewer system is treated in a waste water treatment facility, municipalities and cities desire to keep the water intended to be transferred by the storm water sewer, which does not require treatment, from entering into the sanitary water sewer. Allowing clean storm water into the sanitary sewer system unnecessarily consumes capacity in the waste water treatment facility while increasing the costs of treating the water. When excessive storm water enters the waste water treatment plant, the waste water treatment plant may not have the capacity to treat the large amount of water causing untreated water, including raw sewage, to be discharged into the environment which can potentially cause an environmental disaster. 
   One of the major contributors of clean storm water entering the sanitary sewer is the design of most manhole structures which provide access to the sanitary sewer. The manhole box, typically a junction box, is positioned below ground level and has a through hole in the upper surface. A series of concrete rings called risers are positioned about the through hole on an upper surface of the manhole box. The risers bring the manhole structure up to approximately ground level while providing access to the manhole. A manhole cover frame is positioned on the upper surface of the upper riser such that the upper surface of the frame is at ground level. The manhole cover fits within the frame. 
   After the manhole box, the series of risers, the frame, and the cover are placed in the selected positions, the hole is backfilled to secure the structure in position. Water from rain and melting snow runoff can seep through the ground and enter the sanitary sewer system through seams between the manhole box and the first riser, between the seams between the risers, between the top riser and the frame and also between the frame and the manhole cover. 
   Besides having to treat clean runoff water in the waste water treatment plant, seepage of water also causes soil erosion around the manhole structure. As water enters into the sanitary sewer system through the manhole structure, the water also carries the surrounding soil into the manhole box. As the soil is eroded from around the manhole structure, a cavity is formed which over time will cause the soil above the cavity to collapse. When the soil collapses around the manhole cover, the surface needs to be filled in which adds additional repair expenses to the city or municipality. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention includes a device from preventing water from entering a manhole. The device includes a body having first and second portions that are integrally formed. The first portion extends along and above a periphery of the opening of the manhole and the second portion extends upwardly from the first portion and provides access to the opening of the manhole. Preferably, the first portion includes a downwardly extending lip disposed along an outer vertical surface of the manhole. In addition, a cap is positionable on the second portion to prevent water entering the manhole from the manhole&#39;s opening. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a partial sectional view of the present invention disposed within a manhole. 
       FIG. 2  is a perspective view of the insert of the present invention disposed on an upper surface of a box of a manhole. 
       FIG. 3  is a perspective view of a plurality of risers disposed on an upper surface of the insert wherein the plurality of concrete risers are disposed about the chimney of the insert. 
       FIG. 4  is an alternative to concrete risers where a form is disposed about the insert where concrete is poured between the insert and the form. 
       FIG. 5  is a perspective view of the insert of the present invention including a manhole cover frame disposed on a top surface of the upper riser. 
       FIG. 6  is an exploded perspective view of the present invention. 
   

   DETAILED DESCRIPTION 
   The present invention includes a device generally illustrated at  10  in  FIG. 1  for use within a manhole assembly  40 . The device  10  prevents leakage of surface water and dirt infiltration into the manhole assembly  40 . The device  10  includes an insert  12  and a cap  14 . 
   Referring to  FIGS. 1 and 6 , the manhole assembly  40  includes a box  42  positioned below ground level  11 . The box  42  has an opening  44  through an upper surface  46  which provides access to an interior  43  of the box  42 . The box  42  can provide access to a utility junction box such as banks of telephone or electric switches as well as sewer systems such as a junction for several pipes in a sewer system. 
   Referring to  FIGS. 1 ,  2  and  6 , a bottom surface  18  of a plate  16  of the insert  12  is positioned adjacent the upper surface  46  of the box  42 . A peripheral edge  22  of the plate  16  extends beyond an exterior surface  48  of the box  42 . A first lip  24  extends downwardly from the bottom surface  18  of the plate  16  and preferably along the peripheral edge  22  of the plate  16  such that a distal edge  26  of the first lip  24  is disposed below the upper surface  46  and about the exterior surface  48  of the box  42 . Because the distal edge  26  of the first lip  24  extends below the upper surface  46  of the box  42 , the first lip  24  serves as a water seal diverting water into the soil below the upper surface  46  of the box  42 . 
   Extending substantially centrally upwardly from the plate  16  is a chimney  28  having a substantially central passageway  30  aligned with an aperture  32  in the plate  16  and the through hole  44  in the upper surface  46  of the box  42 . The chimney  28  is slightly tapered towards its upper edge  29  primarily for nesting several inserts  12  one on top of each for storage and shipping purposes. Although a chimney  28  having a circular cross-section is preferred, other cross-sectional configurations are within the scope of the invention. 
   The insert  12  is preferably of a unitary (integral) construction, molded from a plastic (polymer) such as polyethylene. Polyethylene is very suitable material of construction, being corrosion resistant to sewage gases being produced within the sewer system and to many liquids including water. 
   With the insert  12  positioned in a selected position upon the box  42 , at least one concrete riser  50  is disposed about the chimney  28  and adjacent a top surface  17  of the plate  16  as illustrated in  FIGS. 1 ,  3  and  6 . Additional concrete risers  52 ,  54  are disposed about the chimney  28  and stacked upon each other such that an upper surface  56  of the upper riser  54  is a selected distance from ground level  11 . 
   As illustrated in  FIGS. 1 and 6 , the central passageway  30  of the chimney  28  forms the entry into the box  42 . The concrete risers  50 ,  52 ,  54  are also protected from corrosion from sewage gases within the manhole structure  40  due to the polyethylene barrier created by the chimney  28  of the insert  12 . Since the insert  12  is preferably constructed from a plastic, the chimney  28  can easily be cut to a selected height and can be customized for manhole structures of different depths between ground level  11  and the upper surface  46  of the box  42 . 
   Referring to  FIGS. 1 ,  5  and  6 , a manhole cover frame  58  is positioned on the upper surface  56  of the upper riser  54  with the upper edge  29  of the chimney  28  of the insert  12  extending within an opening in the manhole frame  58 . Prior to installing a manhole cover  40  within the manhole frame  56 , the cap  14  is positioned over the upper edge  29  of the chimney  28  to provide an additional seal within the manhole structure  40 . The cover  14  has a downwardly extending second lip  34 , preferably about the peripheral edge  15 , where the second lip  34  extends below the upper edge  29  and about an outer surface  27  of the chimney  28 . 
   A lifting structure  36  is secured to the cap  14  to aid in positioning the cap  14  over the chimney  28  and removing the cap  14  from the chimney  28 . The lifting structure  36  is preferably an eyescrew. 
   With the cap  14  disposed over the chimney  28 , the manhole cover  60  is placed within the manhole frame  58  as illustrated in  FIGS. 1 and 6 . The void around the manhole structure  40  is backfilled to secure the box  42 , the plurality of concrete risers  50 ,  52 ,  54 , the manhole frame  58  and the manhole cover  60  into position. 
   The device  10  prevents all surface water from leaking or seeping into the box  42 . When water enters through the manhole cover  60  or between the manhole cover  60  and the manhole frame  58 , the water contacts the cap  14  and flows over the second lip  34 , down the outer surface  27  of the chimney  28 , over the upper surface  17  of the plate  16  and down the first lip  24 . After flowing off of the first lip  24 , the water disperses into the soil below the upper surface  46  of the box  42  thereby preventing any water from entering the box  42 . 
   When water enters the manhole structure  40  through seams between the risers  50 ,  52 ,  54  or between the upper surface  46  of the box  42  and the bottom riser  50 , the water runs down the outer surface  27  of the chimney  28 , over the upper surface  17  of the plate  16  and down the first lip  24 . After flowing off of the first lip  24 , the water disperses into the soil without entering the box  42 . 
   Because the second lip  34  of the cap  14  is below the upper edge  29  of the chimney  28 , water is prevented from entering between the cap  14  and the insert  12 . Similarly, because the distal edge  26  the first lip  24  of to the plate  16  is below the upper surface  46  of the box  42 , water is prevented from entering between the insert  12  and the box  42 , thereby making the box  42  free from any runoff water. 
   Since the runoff water cannot enter into the box  42 , the soil around the manhole structure  40  cannot enter into the box  42 , thereby preventing erosion around the manhole structure  40 . Because there is no erosion around the manhole structure  40 , the maintenance and repair costs are decreased. Additionally, since surface water leakage is eliminated into the sanitary sewer manholes, large amounts of surface water do not have to be processed by the water treatment plant freeing up capacity and reducing treatment costs. 
   Alternatively, the manhole structure  40  can be constructed by installing the box  42  and the insert  12  on the upper surface  46  of the box  42 . Instead of placing a plurality of risers  50 ,  52 ,  54  on top of each other creating seams through which water can seep, a form  62  is placed about the riser  12  as illustrated in  FIG. 4 . Concrete is poured into a cavity  64  between the form  62  and the insert  12 . After the concrete is set, the form  62  is removed and the manhole frame  58  is placed upon the top surface of the concrete form (not shown). The cap  14  having the second lip  34  is placed on the upper surface  29  of the chimney  28 . With the manhole frame  58  and the cap  14  in the selected positions, the manhole cover  60  is placed within the frame  58 . In the alternative construction, the manhole construction  40  prevents seepage into the box  42  by eliminating the seams between the plurality of risers. Any water that penetrates the concrete form (not shown) flows down the outer surface of the chimney  28 , along the top surface  17  of the plate  16 , down the first lip  24  and into the adjacent soil. 
   Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.