Case Studies

Senate offers a wide range of engineering solutions to private commercial and industrial clients

Millvale Borough – Fornoff St. Reconstruction Project

Millvale Borough, Allegheny County, Pennsylvania

Fornoff Street Reconstruction was part of a 2007 Paving Program in Millvale Borough. The project details were as follows:

Total Cost of Project:  $65,619.00

MILLING (3.0 In)    520 Square yards

– Remove existing asphalt pavement by milling, mill an average 2” – 3”depth for asphalt pavement.

– Remove asphalt from any concrete curb and remove asphalt wedge curb includes dust control and E&S controls as needed to protect drainage systems in both construction and storage areas, includes sweeping and miscellaneous items, including hauling to stockpile.

BASE REPAIR         86 Square yards

– With 2A/25 mm superpave binder course for brick street including but not limited to all material and labor necessary for unclassified excavation of all brick

– Proof rolling, and placing of (2) 4″ lifts of 2A material

(1) 4″ lift of 25.0 mm superpave binder course, to a 1′ nominal depth, complete and in-place.

BASE REPAIR 30 ton

– With 2A/25 mm superpave binder course for brick street including but not limited to all material and labor necessary for unclassified excavation of all brick

– Proof rolling, and placing of (2) 4″ lifts of 2A material

(1) 4″ lift of 25.0 mm superpave binder course, to a 1′ nominal depth, as detailed and directed, complete and in-place.

PAVING FABRIC     860 Sq Yds

– Furnish and install paving fabric (Amoco CEF 4599or equivalent)

2” SUPERPAVE 19.0 MM BINDER COURSE 100 ton

– Install Superpave Asphalt Mixture Design, HMA Binder Course, PG 64-22, 0 to 0.3 million ESAL’s, 19.0 mm mix, 2” depth compacted thickness, in 3” maximum lifts, as per PennDOT 408 complete and in-place including but not limited to all edge and surface cleaning, tack coat, sealing, wedge curb and keyways where required

1.5” SUPERPAVE 9.5 MM FINE GRADED WEARING COURSE

Contractor shall supply and install Superpave Asphalt Mixture Design, HMA Fine-Graded Course, PG 64-22, 0 to 0.3 to million ESAL’s 9.5 mm mix, SRL L, 60 to 110 lb/sy, as per Penn DOT 408 complete and in-place including but not limited to all edge and surface cleaning, sealing, tack coat compaction, and keyways where required for directed, adjustment to grade to all valve boxes, manholes and inlets as required, including overlay of curb (where directed) complete and in-place as per specifications.

Municipal Consent Order Compliance and Repair for I & I Reduction

Background

Each year, sewer overflows affect Pittsburgh’s rivers up to 70 days during the boating season (May 15- October 1) making water unacceptable for recreational contact. In addition, the overflows affect Allegheny County’s primary source of drinking water. Nearly 90 percent of Allegheny County residents get their drinking water from Pittsburgh’s rivers.

In April 2002, Allegheny County municipal officials, engineers and solicitors of the ALCOSAN service area communities began negotiations with the Environmental Protection Agency, PA Department of Environmental Protection (DEP) and the Allegheny County Health Dept. (ACHD) regarding municipal consent orders for their sewage collection systems.  The Consent Decree is designed to promote a coordinated regional approach to the wet weather discharge from ALCOSAN’s system. It requires Alcosan to develop and submit a long-term plan, in coordination with the 83 municipalities that contribute flows to ALCOSAN’s system, to control the wet weather discharges from its system and to ensure compliance with its NPDES permit and the Clean Water Act. The ultimate goal is to address wet weather overflows from local sewer systems and reduce inflow and infiltration.

The two forms of agreements are: The ACHD “Administrative Consent Order” to address Sanitary Sewer Overflows (“SSOs”) in municipalities with separate sanitary and storm sewer systems. The DEP has proposed a “Consent Order and Agreement” to address Combined Sewer Overflows (“CSOs”) in municipalities with combined sewer systems.

Municipality Responsibilities

Compliance with the Consent Decree/Consent Order Agreements requires municipalities to commit to several tasks with required deadlines in order to assess their sewer systems.

In order to assess all requirements set forth in the Consent Decree the municipalities’ first need to retain the services of a Professional Engineer to be knowledgeable of the required tasks and maintain the appropriate level of oversight regarding the completion of all tasks.

Consent Order Agreements require communities to address the sewage overflow issues through two initial phases. In Phase I, municipalities will need to assess their sewer systems through physical survey/visual inspection, GIS mapping, cleaning and televising the system (CCTV), dye testing of households, enforcement of illegal connections, ordinance development, and deficiency corrections to sewers and sewer structures.  Many of these tasks can be completed by the municipality for one sixth (1/6th) of sewer system per year.  In Phase II, communities are required to complete flow monitoring, which indicates how much wastewater (and in some cases, stormwater) the sewage system is carrying during both dry and wet weather. This information will help communities develop a long-term wet weather control plan, in cooperation with ALCOSAN to sustain rehabilitation efforts into the future.

Senate Engineering Company Consent Order Experience

Senate has many years of Consent Order Compliance experience and has assisted our Allegheny County clients (Blawnox, Braddock Hills, Reserve Township, Verona , Wilkins Township) with various Phase I tasks such as:

Physical Survey/Visual Inspection:

Complete inspection of a municipality’s combined or separate sanitary sewer system that directly or indirectly are tributary to the ALCOSAN Collector System. System components constructed or reconstructed since 1995 are exempt.  Physical survey includes items such as: all accessible manholes, exposed sewer lines, SSO structures, siphon chambers, pump stations, force mains, diversion chambers, outfall pipes and structures. Also included are identifying defects related to safety, structural stability, accumulated debris, evidence of surcharging, or any other condition that reduces hydraulic flow of the sanitary sewer system.

Closed Circuit Television (CCTV) Internal Inspection

Senate has successfully managed municipal CCTV projects for our Consent Order clients. CCTV consists of internally camering and recording DVD video (mpeg format) and data (Wincam software, ArcGIS software compatible, Access database) for a community’s sanitary sewer system that directly or indirectly runs to the ALCOSAN Collector System.  The CCTV inspection shall record all defects that allow infiltration into the system, all structural defects, all defects that diminish the carrying capacity of the sewer, all defects in siphons, combined regulator structures, diversion chambers, and outfall pipes. The CCTV inspection shall include all A/V documentation with a written report summary of root locations, defective joints, and pipes, sewer line depressions, break in lateral connections, grease and sediment accumulations.  CCTV inspections shall report a location reference and defect code for level of severity as noted by the NASSCO uniform ranking and rating system.

Sewer System Mapping

Senate Engineering Company’s GIS Department has worked with our Consent Order municipal clients and contractors to build a comprehensive GIS inventory of their sewer system, and become the steward of their data.  A GIS, or geographic information system is a collection of computer hardware, software, geographic data, and personnel which combined can capture, store, analyze, and update information about a specific place.  Information is displayed in a “layer cake” fashion that can be visualized to discern spatial and other relationships between the data and area of interest.  GIS can be an invaluable tool for communities which are under the Consent Decree and concerned about wet weather issues.

Senate has worked with our clients to create complete sewer system maps by means of the physical surveys, as-built drawings of the sewer systems, combined with base map layers from Allegheny County and Three Rivers Wet Weather. The Consent Order mandates following a GIS Protocol for creating and submitting data in a certain format (ESRI compatible format, and FGDC metadata standard). The maps and features created using GIS were verified using GPS (Global Positioning System) or by ground monitoring or land survey. Senate has aided our communities in creating GIS sewer layers and technical attribute data such as:

-Sewer line locations  – Size of sewer line – Direction of flow

-Field verified locations of manholes, catch basins, outfalls, pump stations, force mains

-Known points of sewer overflow (SSO, manhole overflow, basement backups)

-Downstream/Upstream manhole ID   -Pipe diameter   – Pipe material -Pipe shape   -Sewer type (combined, sanitary)

-SubType (collector, interceptor) – Pipe grade

-Rehabilitation Type (spot repair, trenchless) -Manhole invert elevation  -Manhole rim elevation   -Unsewered Areas

Sewer System Dye Testing and Ordinance Creation

In collaboration with our municipal clients, Senate has coordinated community wide dye testing projects. Dye testing of all structures to verify they are not connected to the sanitary sewer is a requirement of the Consent Order. All structures such as roof leaders, yard and driveway drains are tested to determine if they are sources of surface stormwater inflow and infiltration.  Also, all private and municipal catch basins within 100 feet of the sanitary sewer are tested.  Documentation of any illegal connection is required in the GIS map and the relational database.  Institution and enforcement of an ordinance prohibiting connections of surface stormwater to sanitary systems is also a requirement of this program.  This ordinance shall include a stipulation which requires at the time of all property sales, a visual inspection and dye test must be done to ascertain any illegal connections.  Senate has supported communities in the creation and adoption of many such ordinances.

Sewer System Deficiency Repairs

The Consent Order requires complete repair of all structurally deficient items as discovered by physical inspection and CCTV internal inspection. These structures include repair of manholes, sewer lines, pump stations force mains, etc. with elimination of stream conveyance by the sewer system and receiving stream backflow into the sewer system. The municipality shall initiate repair to the most significant defects (grade 5) first, such as collapsed sections of sewer lines, complete sewage blockage and any other defect the overseeing Professional Engineer determines immediate attention.

Conclusion

Under the proposed consent decree, ALCOSAN has agreed to a multi-year strategy to upgrade the sewage systems serving Pittsburgh and 82 surrounding municipalities. These Consent Orders pose serious issues for Allegheny County municipalities; a municipality is obligated to commit personnel and finances to complete assigned tasks by specified deadlines. Failure to execute the consent orders may be cause for agencies to use fines and penalties as enforcement.