I-126 (Elmwood Ave) Bridge Sewer Relocation.
Relocation of approximately 1100 LF of 8-inch gravity sewer, 200LF of 2-inch sewer force main, along with multiple lateral lines, and manhole adjustments.
The purpose of this project is to provide technical engineering, administrative, and construction phase support to the City of Columbia for find-and-fix rehabilitation of a portion of the City’s sanitary sewer system. Rehabilitation efforts are intended to identify and correct problems that may lead to sanitary sewer overflows (SSOs) through structural, operations and maintenance, and infiltration and inflow (I/I) related defects of City assets. The intent of this project is to meet the requirements of the Continuing Sewer Assessment Program (CSAP) and the Infrastructure Rehabilitation Program (IRP) which are components of the Consent Decree under which the City is performing this work.
Technical consulting support to the City of Columbia (CITY) for a water main and sewer line relocation project around a roadway improvement project, including utility coordination, evaluation of alternative alignments, engineering and design, and construction phase services for the project. Scope of this work is assumed to include the relocation of approximately 1,600 linear feet of 6-inch water main and 250 linear feet of 21-inch gravity sewer with upgrade to 36-inch. It is assumed that the 8-inch gravity sewer line will remain in place and this scope includes connection to the new 36-inch gravity main, protection measures, and adjustment of manhole rims as required. This scope of work also includes design of permanent maintenance access points on the north and south sides of the roadway to the 36-inch sewer line.
This project proposes a 36-inch diameter extension of the existing Saluda River Force Main in order to relocate the force main outfall into the City’s gravity sewer system. The proposed force main will be revised to extend from its current outfall at Manhole 25109MH on the north side of the Saluda River to a new outfall location at 25213MH, located on the south side of the Saluda River. The force main will extend for approximately 3,500 linear feet; the exact length required shall be verified by the Consultant and coordinated with the City and CW2020.
Sewer relocation projects around the widening of Leesburg Road from near Fairmont Road to near Lower Richland Boulevard for approximately 3.9 miles.
New sludge thickening facilities will be designed to consolidate PS + WAS thickening from both liquid process trains and to accommodate the Metro WWTP’s current 60 mgd design flow rating with flexibility for future expansion to 80 mgd.
As part of the City’s Capacity Assurance Program (CAP) required under the EPA’s May 2014 Consent Decree, the City of Columbia has evaluated collection system capacity to convey the projected future flow in the Crane Creek sewer basin from 2020 through full buildout of the sewer basin. Based on simulations using the Hydraulic Model, the results suggest that the existing Crane Creek trunk sewer, North Columbia Pump Station, and Rocky Branch/Congaree outfall trunk sewer cannot properly convey peak 2-year storm event wet-weather flows, as required by the Consent Decree, beginning with the 2020 planning period. The City is proposing the construction of an 8 million-gallon (MG) equalization storage tank and a corresponding Crane Creek Storage Pump Station (CCSPS) with a flow rate capacity of 25 million gallons per day (mgd) to address immediate 2020 system capacity deficiencies for the Crane Creek basin. The storage tank and pump station will be constructed on City property at the Old Eau Claire Wastewater Treatment Facility, which is located near the confluence of the Smith Branch and Crane Creek trunk sewers.
This project proposes a permanent storage and feed system for magnesium hydroxide slurry for treatment Train 2 at the Metro WWTP. Currently, Train 2 has a temporary magnesium hydroxide chemical feed system which provides supplemental alkalinity to support the nitrification process. The system shall be a standalone system to operate within a range to effectively supplement alkalinity using magnesium hydroxide slurry to accommodate fluctuations in nitrogen and alkalinity plant loading. Since the 2015 PER, the CITY has implemented a magnesium hydroxide feed program in the collection system for odor control which may influence supplement feed requirements and operational ranges for Train 2. The 2015 PER is also currently being updated, and the process recommendations in the PER Update may also impact alkalinity feed requirements in both Train 1 and Train 2.
This project consists of a new gravity sewer for a distance of 11,000 linear feet with a new 27-inch and 36-inch diameter pipe to replace or supplement the capacity of the existing sewer that runs along a cross-country easement all parallel to Kinley Creek from Linsbury Circle approximately to the Saluda River Pump Station. This project is the second phase of conveyance capacity improvements required to avoid SSOs in the Kinley Creek area of the Saluda River Basin.
Funding for MWWTP projects necessary for maintaining efficient performance and compliance. Projects may include: Train 2 Mag System, dewatering roll-off pad, sec clarifier weir replacement, Leachate/sidestream EQ, biosolids staging and storage, digester pumping improvements, T2 aeration improvements, T1 aeration modifications, Sec Clarifier 5/6 rehab, PTF course bar screening.
The West Columbia Pump Station Improvements are required to increase the firm pumping capacity to 26 million gallons per day (mgd) to meet sewer flow rates through 2040. This project will increase the capacity of the pumping station to convey flows to the Metro Wastewater Treatment Plant and avoid SSOs in West Columbia.
This project is for Train 2 Aeration & Dewatering System Upgrades - centrifuge, controllers, and blowers.
The purpose of this project is to assist the City of Columbia in providing the final design and construction services which were determined under a previous project scope SS7454 and provided in a Preliminary Design Report (PER). This agreement includes final design and construction services for the selected alternative as presented in the Preliminary Engineering Report and includes the design of two segments of gravity sewer upstream of the Broad River PS which consist of approximately 5,560 LF of new 24-inch gravity sewer, and approximately 5,100 LF of new 42-inch gravity sewer, and includes two segments of force main downstream of the Broad River PS consisting of the design of approximately 3,900 LF of new 24-inch force main and the analysis and condition assessment of a force main section that consists of approximately 4,800 LF of 20-inch force main.
Atlantic Drive Sewer Extension.
The Disinfection Improvements for the Metro WWTP Consent Decree Early Action Project (EAP) have eliminated plant dependence on hazardous gaseous disinfection chemicals and aging gas feed equipment which posed a safety threat to personnel and the surrounding community.
The Metro Wastewater Treatment Plant Train II DAF Improvements Consent Decree Early Action Project (EAP) replaced worn process equipment and assessed other components for wear and future replacement needs. The project allowed the City to meet SCDHEC's effluent requirements and increase efficiency and reliability.
The Metro Wastewater Treatment Plant Standby Pump Station Improvements and Effluent Flume Modifications Consent Decree Early Action Project (EAP) included improvements to the standby pump station's capacity and hydraulic operating conditions, and modifications to the effluent flume structure.
The Metro Wastewater Treatment Plant Aeration Consent Decree Early Action Project (EAP) provided upgrades to four aeration treatment basins and critical operating processes increasing efficiency and reliability and reducing costs.
The improvements during this Consent Decree Early Action Project (EAP) to the Broad River Pump Station addressed the existing hydraulic, electric, structural and HVAC deficiencies and increased the station's pumping capacity thereby reducing the potential for sanitary sewer overflows.