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Public Open House. December 13, 2010. NEW JERSEY WATER SUPPLY AUTHORITY Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road. Introductions. New Jersey Water Supply Authority Henry Patterson Ed Buss Sharmila Rahman Urban Dredging Consultants Joint Venture Ram Mohan
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Public Open House December 13, 2010 NEW JERSEY WATER SUPPLY AUTHORITYDredging of the Delaware and Raritan Canal from Kingston to Amwell Road
Introductions • New Jersey Water Supply Authority • Henry Patterson • Ed Buss • Sharmila Rahman • Urban Dredging Consultants Joint Venture • Ram Mohan • Robert DeLorenzo • Other Joint Venture Members • Carol Beske – ACT Engineers • Eric Rosina – ACT Engineers • Lynn Brass-Smith – Amy S. Greene Environmental Consultants, Inc. URS • Anthony McNichol
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Introductions • Primary objective, goals, and critical elements • Dredging technologies evaluated • Sediment characteristics and beneficial reuse • Phasing of construction • Traffic control Agenda • Cultural resource investigation • Permitting requirements • Environmental information document and public hearing • Public outreach • Project schedule • Open discussion
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Project Objective • Remove an estimated 250,000 cubic yards of sediment from the Canal in order to restore its flow capacity • Project Goals • Protect the historical integrityof the Canal • Maintain technical quality • Maintain water supply • Critical Project Elements • Develop dredging plan acceptable to stakeholders • Focused outreach to public officials and stakeholders
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Project Area
Dry Excavation Mechanical Dredging Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Dredging Technologies Evaluated Hydraulic Dredging
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Pre-Sediment Removal Activities • Tree Trimming • Trimming trees to allow equipment access to sediment • Submerged Aquatic Vegetation (SAV) Removal • Remove SAV to prevent clogging of sediment removal equipment • Debris Removal • Remove debris to maximize sediment removal production
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Dry Excavation • Canal separated into reaches varying in manageable lengths • Each Reach with Access Area and Truck Ramp • Flow Bypassed through Work Area (portadam or other structure with piping to convey flow into the Millstone) • Flow diversion structures to facilitate removal on short notice to safeguard against high flow (flood) events
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Dry Excavation (cont.) • Low-ground pressure excavators and dozers used to excavate sediment • Sediment within the dewatered Canal section will be reworked and air dried prior to excavation • Allows for higher degree of accuracy during removal (increased volume control) • Requires intensive water management operations
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Mechanical Dredging • Conducted in the wet using hydraulic excavator operating from shallow-draft barge or flexi-float system • Hydraulic clamshell bucket to be used on dredge to minimize turbidity (1-3 cubic yard bucket) • Dredge maneuvering with non-penetrative methods (anchors, guidelines, etc.)
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Mechanical Dredging (cont.) • Dredged sediment to be placed into 10-20 cy scows or 20 cubic yard containers on flexi-floats • Scows unloaded to trucks or hydraulically pumped to dewatering area • Sediment dewatered by air-drying, stabilization, geobags, or mechanical dewatering system • Potential for multiple dredge units operating simultaneously
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Hydraulic Dredging • Conducted in the wet using hydraulic cutterhead dredge • Requires separate Submerged Aquatic Vegetation (SAV)/debris removal operations prior to dredging to prevent clogging • Dredge maneuvering with non-penetrative methods (anchors, guidelines, etc.) • Booster pumps required to facilitate transport of dredged sediment through plastic pipeline to dewatering area
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Hydraulic Dredging (cont.) • Dredged sediment to be dewatered using geobags or mechanical dewatering system • High comparative production rate • Water generation significantly more than other investigated removal methods • Requires extensive water treatment/water management operations
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Sediment Dewatering/Stabilization • Technologies evaluated: • Air-drying • Stabilization • Geotextile tubes • Centrifugation (hydrocyclones) • Mechanical presses (belt filter, plate and frame) • Rapid dewatering
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Air-Drying • Allow dredged sediment to passively dewater by gravity draining and evaporating water from stockpiled sediment • Small dozer to work sediment to increase speed of dewatering • Stabilization • Blend dredged sediment with portland cement or other material to absorb free water
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Geotextile Tubes • Pump dredged sediments through HDPE pipeline directly to geotextile tubes • Dose polymers to increase dewatering efficiency • Following dewatering, cut tubes and excavate material • Produce “truckable” material • Centrifugation (Hydrocyclones) • Quickly separate solids from a slurry • Typically only the initial step in a series of dewatering procedures
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Mechanical Presses (Belt Filter, Plate and Frame) • System receives sediment slurry • Use combinations of presses to extract free water from sediment • Produces “truckable” material • Rapid Dewatering • System receives sediment slurry • Use multiple steps and dewatering polymers to rapidly separate solids and reduce water content of sediment • Produces “truckable” material
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Sediment Characteristics and Beneficial Reuse Frequently Detected Compounds/Constituents • 32 individual samples • Represent vertical average at each location • Gravel = 6% • Sand = 29% • Silt/Clay = 63% • Organics = 2%
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Phasing of Construction • Number of reaches • Reach delineation • Reaches dredged in Year 1 (2013) • Reaches dredged in Year 2 (2014) • Intermediate reaches (minimize disruptions to recreational boaters-canoe rental) • Signage • Towpath and Road Detours
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Conceptual Traffic Routes
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Section 106 of the National Historic Preservation Act: Cultural Resources Investigations and SHPO Review
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Section 106 Review of the NHPA – requires the consideration of potential adverse effects on cultural resources within the project area • As the consultant, URS will conduct a Phase IA Background Research Investigation, identifying areas of potential sensitivity within designated project footprints • Phase IA report is submitted to the New Jersey State Historic Preservation Office for comment and consultation • The SHPO then makes recommendations to the client for the treatment of resources within a given Area of Potential Effect (APE) • These recommendations may include one or more of the following: • No impact, limited subsurface testing, or on-site monitoring during project implementation • URS carries out Phase IB Investigations within the Project Area
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Potential Resources within the Dredging Project Area • Features directly associated with the Canal: • Clay liner • Rip-rap • Armor stone • Waste weirs • Dams • Spillways • Wharves and dock features • Slips and scuttled vessels
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Potential Resources within the Dredging Project Area • Historic Structures and Archeological Resources
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Potentially Required Permits • U.S. Army Corps of Engineers • Delaware and Raritan Canal Commission • NJ Department of Environmental Protection • Freshwater wetlands • Flood hazard area • No net loss reforestation • Water lowering • Fish stocking • Water Quality Certification • Section 106 consultation • Somerset-Union County Soil Conservation District • NJPDES Construction • Soil erosion and sediment control
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Level II Environmental Information Document • Key Environmental Issues • Public use • Surface water • Floodplains and riparian zones • Biotic (plant and animal communities) • Forest • Wetlands • Threatened and endangered species • Cultural resources • Impact on water users
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Staging Area and Site Access Selection Process Wetland Investigation • Secondary source data • Preliminary field investigation • Wetland delineation and survey
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Project Schedule
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • Public Officials Briefings: July, September, February • Montgomery • Rocky Hill • Franklin Township • Hillsborough • South Brunswick • Millstone Borough • Somerset County • Coordination Meetings • NJDEP • D&R Canal State Park • D&R Canal Commission • D&R Canal interest groups briefing
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • D&R Canal Interest Groups • Mapleton Preserve Commission • Millstone Valley Preserve Coalition • Kingston Historical Society • Kingston Village Advisory Committee • Raritan Millstone Heritage Alliance • Somerset County Cultural Heritage • Meadows Foundation • Griggstown Historical Society • Griggstown Canoe • Canal Society of New Jersey • D&R Canal Watch • Future Meetings: February 2011 • Public officials briefings • Public hearing
Dredging of the Delaware and Raritan Canal from Kingston to Amwell Road • View NJWSA Website for Continuing Project Updates http://www.njwsa.org/html/canaldredging.html