Home

Contact Us

Management and Staff

Meetings and Minutes

Policies and Resolutions

Regulatory Obligations

Facility Description

Plant Processes

Projects

Current Projects

Flow Reports

Links

Sewer Use Rules and Regulations - September 2003

Article V - Exclusion of Extraneous Flows, Combined Sewer Overflows, and Nine Minimum Controls

Section 5.01: Exclusion of Extraneous Flows

1. The discharge of storm water and other extraneous flows, whether from direct connections, conveyances or other sources, that are not designed, constructed or permitted to carry municipal wastewater flows, are strictly prohibited.

2. All persons connecting to the regional and/or local sewerage systems shall provide complete and effective means and measures for excluding storm water and extraneous flows in the event a connection is made to a sanitary sewer .

3. No person or municipality connected to a sanitary sewer shall connect or cause to connect thereto any roof drain, foundation drain, area drain or any other storm water conveyance, or permit any such conveyances or drains to remain connected thereto, nor shall they permit, allow or cause to enter into any sanitary sewer any storm water, spring (ground) water or extraneous flows from any other source.

4. Member Municipalities shall adopt and enforce ordinances, resolutions, rules and regulations their jurisdiction that will require storm water and extraneous flows to be removed from facilities that convey flows to the regional sewerage system. Such ordinances, resolutions, rules and regulations would include but not be limited to, a dye testing program that shall require all facilities and structures, residential, commercial, industrial or otherwise, before being sold, to have all storm water conveyances, downspouts, area drains, foundation drains and sanitary laterals tested to ensure the facilities are properly designed, constructed, operated, maintained and connected. Any storm water or extraneous flows discovered as a result of such testing shall be remedied before the sale of the property is finalized.

 

Section 5.02: Combined Sewers

1. Certain Municipalities (Borough of Irwin and Manor Borough) own and maintain facilities that are permitted, by permit and design, to discharge combined sewerage flows to the regional sewerage system.

2. The Authority owns, operates and maintains three CSO Regulators at the municipal connections to the regional sewerage system. These connections are currently permitted by the PaDEP and EPA as part of the Authority's NPDES Permit.

3. The connecting Municipalities shall, whenever possible or whenever required by any governmental agency having jurisdiction, eliminate, through whatever means necessary , storm water and extraneous flows into this system.

4. The connecting Municipalities shall not add, cause to add, or permit to add, to the regional sewerage system, any additional storm water or extraneous flows over and above that for which the system was originally designed and constructed.

 

Section 5.03: Nine Minimum Controls

1. The Authority, as required in its NPDES Permit, must comply with the EPA Combined Sewer Overflow Policy published in 1994. The objectives of this policy are to:

a. Ensure that if there are overflow from combined sewer systems (CSS), these CSOs are only a result of wet weather.

b. To bring all wet weather CSO discharge points into compliance with the technology- based and water quality-based requirements of the Federal Clean Water Act.

c. To minimize the impact of CSOs on the water quality, aquatic biota and human health.

2. As such, the Authority requires all Municipalities to comply with the Nine Minimum Controls (NMCs) as provided for in the EPA Combined Sewer Overflow Policy. Additional information regarding the implementation of the NMCs can be found in the EPA publication titled Guidance for Nine Minimum Controls, which is available on their web site at http://epa.gov. The NMCs are described in more details as follows:

a. Proper operation and regular maintenance programs for the sewer system and CSO outfalls

Municipalities shall identify and establish operation, maintenance and inspection procedures to ensure that a Combined Sewer System (CSS) and the treatment facility will function so that the maximum amount of combined sewage will be conveyed and treated and still comply with the NPDES permit requirements of the facility. Implementation of this NMC shall include, but not be limited to the following steps:

1) Assess existing O&M procedures and how well they are being implemented.

2) Determine whether the O&M procedures should be improved to satisfy the intent of the CSO policy.

3) Develop and implement the improvements to address the CSOs.

4) Document any actions taken and report them to the PaDEP .

5) Documentation for this NMC to demonstrate that the appropriate activities have been implemented or considered include:

   i) An identification of CSS components requiring routine operation and maintenance;

   ii) An evaluation of operation and maintenance procedures to include regular inspections, sewer catch basin and regulator cleaning, equipment and sewer collection system repair or replacement where necessary;

   iii) Written operation and maintenance procedures for the CSS and CSO structures;

   iv) Resources allocated (manpower, equipment, and training) for maintenance of the CSS and CSO structures.

b. Maximum use of collection system for storage

Municipalities shall maximize storage in the collection system and make modifications to the system components to enable the system itself to store wet-weather flows until downstream facilities can accept the flows. Any modifications should be evaluated to ensure that they will not cause problems such as basement or street flooding. All modifications anticipated or completed must be documented for the PaDEP. Examples of control measures are:

1) Collection system evaluation to identify deficiencies that restrict the use of the system' s storage capacity;

2) Overflow outfall gate maintenance and repair;

3) Adjustment of CSO regulator settings; and

4) Evaluation of localized upstream detention such as using parking lots to store runoff flow, if required.

5) Removal of obstructions to the flow, which could include pipe size restrictions.

6) The Authority could demonstrate its efforts to comply with this NMC by documenting any of the following:

   i) Analyze and/or study alternatives to maximize collection system storage;

   ii) Describe procedures in place for maximizing collection system storage;

   iii) Prepare a schedule for implementation of modifications to the CSS and CSO facilities to maximize storage during wet-weather events;

   iv) Document actions taken to maximize storage in the system;

   v) Identify additional potential long-term measures to increase storage and/or reduce inflow in the collection system. These measures would require additional analysis and study beyond the scope of this study.

c. Review and modification of pretreatment requirements to ensure that CSO impacts are minimized

Municipalities shall control and/or minimize the impact of discharges into the sewage system from commercial and industrial users of the system during wet-weather events. This objective can be met by modifying inspection, reporting and oversight procedures for these entities. PaDEP will require documentation that a diligent effort has been made to address these CSO impacts. Such documentation could include:

1) An inventory of non-domestic dischargers;

2) Descriptions of modifications made to the pretreatment program and/or regulations;

3) A schedule for implementing modifications, including amending sewer use ordinances.

d. Maximization of flow to the Publicly Owned Treatment Works (POTW) for treatment

Municipalities shall make modifications to the sewage system and CSS and the POTW to allow as much wet-weather flow to reach the POTW as possible. The goal is to minimize the magnitude, frequency and duration of CSOs. The Federal EPA recommends that the following minimum measures be considered in implementing this control.

1)  Determine the capacity of the interceptors and ensure that the full capacity is available.

2)  Analyze existing records to compare flows processed by the plant during wet weather and dry periods and determine the relationships between performance and flow.

3)  Compare the current flows with the design capacity of the overall facility, as well as the capacity of the individual unit processes. Identify the location of available excess capacity.

4)  Determine the ability of the POTW to operate acceptably at incremental increases in wet-weather flows, and estimate the effect on the POTW's compliance with the effluent limits in its NPDES permit.

5)  Determine whether unused treatment units at the POTW can be used to treat or store wet weather flows.

6)  Develop project and O&M cost estimates for the proposed modifications.

7)  The Authority must provide documentation for this NMC which could include the following:

8)  A description of any planned physical changes that are part of this control;

9)  A cost estimate and implementation schedule for each of the changes listed;

10) A description of the additional studies and analyses, if any, that may be performed.

e. Elimination of CSOs during dry weather

Municipalities shall take measures to eliminate overflows during dry weather periods. Since the NPDES program prohibits dry-weather overflows (DWO), the requirement for DWO elimination is enforceable independent of any program for the control of CSOs. DWO control can include modifications to the sewage system and CSS facilities and changes and improvements in O&M procedures.

Documentation for this NMC shall include the following:

1) A summary of alternatives considered and actions taken to identify and correct DWOs;

2) A description of the procedures for notifying PaDEP of DWOs and a summary of reports submitted;

3) A summary of periodic reports on the progress made toward eliminating DWOs.

f. Control of solid and floatable materials in CSOs

Municipalities shall take measures to reduce or, preferably, to eliminate visible floatables and solids through modifications and additions to the CSO facilities. Such modifications could include the use of baffles, screens and racks to remove coarse solids, and skimmers and booms to help remove floatables.

Documentation for this NMC shall include the following:

1) An engineering evaluation of procedures or technologies considered for controlling solid and floatable materials;

2) A description of CSO controls in place for solid and floatable materials;

3) A cost estimate and implementation schedule for each of the control measures being implemented;

4) Review and modification to street sweeping and catch basin cleaning methods, procedures and schedule.

5) Documentation of any additional controls to be installed or implemented.

g. Pollution prevention program to reduce contaminants in CSOs

Municipalities shall take measures to keep contaminants from entering the sewage system and CSS and the receiving waters via the CSO. Most of the methods suggested by the EPA involve behavioral change rather than construction of physical modifications to the collection and treatment systems. These control measures shall include, as appropriate:

1) Street cleaning during dry weather periods;

2) Public education programs;

3) Solid waste collection and recycling;

4) Product ban/substitution;

5) Control of product use such as fertilizer and pesticides, de-icing salts, etc.;

6) Water conservation methods.

The Authority must provide documentation that they have made diligent efforts in evaluating this minimum control and have a clear understanding of the measures to be taken. This documentation could include the following:

1) A summary of the alternatives considered;

2) A list and description of the measures planned for implementation and the name of the individual or department responsible;

3) A cost estimate and the implementation schedule;

4) An estimate of the benefits expected from the minimum control actions;

5) Samples of the public educational material planned for use;

h. Public Notification

Municipalities shall take measures to inform the general public of the location of CSO, outfalls, the actual occurrences of CSOs, the possible health and environmental effects of CSOs and the recreational or commercial activities curtailed as a result of the CSO events. Public notification measures shall include the following:

1) Posting at the affected area of use;

2) Posting at selected public places;

3) Posting at CSO outfalls;

4) Notices in newspapers or on radio and TV news programs;

5) Authority web site;

6) Telephone hotline for interested citizen calls.

7) Limitations associated with this control are related to the degree of assurance that the notification method selected will provide the necessary information to the appropriate portion of the public sector. Documentation of the efforts made could include the following:

8) A list and description of the measures planned for implementation and the name of the individual or department responsible;

9) The procedures or protocol for issuing notices;

10) Samples of the public educational materials used or planned for use and a photograph of a typical sign, if applicable;

11) A list of the location where signs are posted (or will be posted);

12) A log of CSO occurrences and associated public notification.

i. Monitoring to characterize CSO impacts and the efficacy of CSO controls

Municipalities shall use visual inspections and other methods to determine the occurrence and apparent impacts of CSOs. This control is an initia! characterization of the CSS to collect and document information of CSOs and known water quality problems and incidents that reflect use impairments caused by CSOs. The System Inventory and Characterization Report submitted to PaDEP in November 1998, addresses many of the issues of this control measure. The ongoing flow monitoring at the CSOs also addresses many of the issues. This monitoring will continue. Documentation for this control measure could include the following:

1) Identification of CSOs in the CSS

2) A summary of observed incidents (i.e. the number and location of overflow events, as well as duration, volume, and pollutant loadings, if available )

3) A summary of receiving water impact that is directly related to CSOs (e.g. fish kills, floatables, wash-up episodes, etc.)

4) An assessment of the effectiveness of any CSO control measures already implemented.

Flow monitoring protocol shall be in conformance with the requirements of Appendix A.

Go to Article VI

Return to Article IV

Return to Sewer Use Table of Contents

 

 

Search

WEB SITE DESIGNED BY:  JMS Design Consulting Inc
Send mail to jwtorkowski@wwmaweb.com with questions or comments about this web site.
Copyright 2002 Western Westmoreland Municipal Authority
Last modified: May 3, 2018