Dredge head assembly and related diver-assisted dredging system and methods

Abstract

A dredge head assembly is disclosed. The assembly includes: a shroud having a generally open bottom end and a top end; a screen structure covering the generally open bottom end of the shroud; a suction pipe with a first end connected to the top end of the shroud and a second end configured to be operatively connected with a pump which induces suction; a handle connected to and extending from the shroud and having at least one grasping portion; and one or more vacuum relief valve assemblies, each comprising a valve, at least one opening configured to be in communication with water, and an actuation mechanism positioned to be accessible to a diver. Dredging systems and methods of dredging are also disclosed.

What is claimed is: 
     
         1 . A dredge head assembly comprising:
 a shroud having a generally open bottom end and a top end;   a screen structure covering the generally open bottom end of the shroud;   a suction pipe with a first end connected generally vertically and centrally to the top end of the shroud and a second end configured to be operatively connected with a pump which induces suction;   a circular ring-shaped handle connected to and extending from the shroud and having at least one grasping portion; and   one or more vacuum relief valve assemblies, each comprising a valve, at least one opening configured to be in communication with water, and an actuation mechanism positioned to be accessible to a diver;   wherein the actuation mechanism of the one or more vacuum relief valve assemblies is in close proximity to the ring-shaped handle, and   wherein a width of the shroud is significantly larger than the width of the suction pipe.   
     
     
         2 . The dredge head assembly of  claim 1 , wherein the shroud has a diameter of approximately 30 inches. 
     
     
         3 . The dredge head assembly of  claim 1 , wherein the dredge head assembly is negatively buoyant in freshwater. 
     
     
         4 . The dredge head assembly of  claim 1 , wherein the shroud is made of a polymeric material. 
     
     
         5 . The dredge head assembly of  claim 4 , wherein the polymeric material is high density polyethylene. 
     
     
         6 . The dredge head assembly of  claim 1 , wherein the first end of the suction pipe comprises a fish-mouth shaped opening and the first end of the suction pipe is connected to and over a corresponding fish-mouth shaped opening in the top end of the shroud. 
     
     
         7 . The dredge head assembly of  claim 1 , further including a plurality of water jet nozzles configured to connect to a pump. 
     
     
         8 . The dredge head assembly of  claim 7 , wherein the water jet nozzles are housed within the shroud and circumferentially spaced relative to the screen structure. 
     
     
         9 . The dredge head assembly of  claim 8  wherein the dredge head assembly comprises four water jet nozzles. 
     
     
         10 . The dredge head assembly of  claim 1 , wherein the dredge head assembly is free from mechanical agitation devices. 
     
     
         11 . A diver assisted dredging system comprising:
 a dredge head assembly comprising:
 a shroud having a generally open bottom end and a top end; 
 a screen structure covering the generally open bottom end of the shroud; 
 a suction pipe with a first end connected generally vertically and centrally to the top end of the shroud and a second end configured to be operatively connected with a pump which induces suction; 
 a circular ring-shaped handle connected to and extending from the shroud and having at least one grasping portion; and 
 one or more vacuum relief valve assemblies, each comprising a valve, at least one opening configured to be in communication with water, and an actuation mechanism positioned to be accessible to a diver; and 
   a towing assembly comprising a dredge head support assembly, wherein the dredge head assembly is connected to and suspended from the dredge head support assembly;   wherein the actuation mechanism of the one or more vacuum relief valve assemblies is in close proximity to the ring-shaped handle, and   wherein a width of the shroud is significantly larger than the width of the suction pipe.   
     
     
         12 . The diver assisted dredging system of  claim 11  further comprising a guide barge, wherein the towing assembly is in communication with the guide barge. 
     
     
         13 . The diver assisted dredging system of  claim 11  wherein the dredge head support assembly is stationary. 
     
     
         14 . The diver assisted dredging system of  claim 11  wherein the dredge head support assembly is configured to swing. 
     
     
         15 . The diver assisted dredging system of  claim 11 , wherein the towing assembly is a crane or boom-containing assembly. 
     
     
         16 . A diver assisted dredging system comprising:
 a guide barge;   a dredging vessel comprising a dredge head support assembly;   a towing assembly in communication with the guide barge and dredging vessel, the towing assembly configured to reposition the dredging vessel relative to the guide barge; and   a dredge head assembly connected to the dredge head support assembly of the dredging vessel by a flexible hose, the dredge head assembly comprising   a shroud having a generally open bottom end and a top end;   a screen structure covering the generally open bottom end of the shroud;   a suction pipe with a first end connected generally vertically and centrally to the top end of the shroud and a second end configured to be operatively connected with a pump which induces suction;   a circular ring-shaped handle connected to and extending upward from the shroud and having at least one grasping portion; and   one or more vacuum relief valve assemblies, each comprising a valve, at least one opening configured to be in communication with water, and an actuation mechanism positioned to be accessible to a diver;   wherein the actuation mechanism of the one or more vacuum relief valve assemblies is in close proximity to the ring-shaped handle, and   wherein a width of the shroud is significantly larger than the width of the suction pipe.   
     
     
         17 . The diver assisted dredging system of  claim 16 , wherein the dredge head support assembly is a ladder. 
     
     
         18 . The diver assisted dredging system of  claim 17 , wherein the ladder is a stationary ladder. 
     
     
         19 . The diver assisted dredging system of  claim 17 , wherein the ladder is configured to swing. 
     
     
         20 . The diver assisted dredging system of  claim 16  wherein the one or more vacuum relief valve assemblies are each configured for activation by at least one diver. 
     
     
         21 . The diver assisted dredging system of  claim 16 , wherein the guide barge includes at least two positioning devices. 
     
     
         22 . The diver assisted dredging system of  claim 16 , wherein the towing means is selected from the group consisting of a vehicle and a winching system. 
     
     
         23 . The diver assisted dredging system of  claim 16  wherein the guide barge has a length of at least 50 feet.