SECTION IV OPERATIONS AND MAINTENANCE PROGRAM

Transcription

1 WEST VALLEY SANITATION DISTRICT SEWER SYSTEM MANAGEMENT PLAN SECTION IV OPERATIONS AND MAINTENANCE PROGRAM Operations and Maintenance Program The Operation and Maintenance Program is critical to the fulfillment of the District s mission to serve the residents and businesses within its service area and a significant part of the District s effort in reducing the occurrence of SSOs and mitigating their impact. This program encompasses these major elements: a) Collection System Mapping b) Preventive Maintenance c) Rehabilitation and Replacement d) Staff Training and Certification e) Maintenance and Contingency Equipment a) Collection System Mapping The use of accurate and up-to-date collection system mapping is essential for proper operation and maintenance of a wastewater collection system. The location, size, direction of flow, and other pertinent information of the system s components are utilized regularly by both maintenance and engineering staff. Although the District s mapping is generally very accurate and complete, the location of the lower laterals is one portion of the system mapping that is undergoing improvement. The District has discontinued the use of Sewer Location Maps (paper maps) which are the District s original hand drawn sewer maps. There were a number of disadvantages associated with use of the Sewer Location Maps including: excessive amount of time required to hand draw revisions, long delays in getting updated mapping to the field, difficulty in reading reduced sets, limited staff with ability to draft with ink, deterioration of original linen or mylar map sheets, and the cost and effort needed to duplicate and distribute map sets. Office staff has been utilizing electronic or Geographic Information System (GIS) mapping for several years due to the ease of access from their workstation computers and because GIS mapping is a component of the District s computerized maintenance management system (CMMS), referred to as Lucity. The desire to provide the same degree of accessibility to the field, while selecting a system that can be readily adopted by the typical maintenance worker (user friendly, reliable, and uncomplicated), proved to be a challenging effort. WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 1 of 12

2 Collection System Mapping At the end of 2012, the District began implementation of field hardware and software that provides maintenance and other field staff access to GIS mapping of the sewer system. The hardware consists of Panasonic Toughbook laptops mounted in key service vehicles, and software is referred to as Inframap and was developed by Iwater. In addition to sewer system mapping, aerial maps, property boundaries, and street locations, field staff can readily locate themselves on the map through the laptop s Global Positioning System (GPS) feature. This is particularly important when locating sewer lines that are not in the public right-of-way (easement lines), or when responding to service calls on a stormy night. Other information available to field staff includes work order lists, pipe cleaning history, and pipe asset information (ID number, diameter, flow direction, segment length, material type, and age). The editing feature in the software allows field staff to provide input when changes are needed to the mapping, which are then verified and processed by engineering within a few days. The sewer system mapping used in the field is always upto-date as all changes to the sewer system mapping automatically downloads to the field laptops every afternoon. The portion of the District s sewer system mapping that is undergoing improvement is the lower sewer lateral location. Approximately 18,000 of the estimated 34,500 laterals are currently drawn in GIS with some degree of accuracy, while the remaining 16,500 may be shown, but require verification. This large number of unverified lower lateral locations is due to the fact that many of these locations were never shown on the original Sewer Map Books. Since mid-2009, a Lateral Mapping Program has been in place to investigate and survey property line cleanouts. By utilizing GPS survey equipment the exact location of the lower lateral can be determined. Based on experience to date, only 34% of properties investigated have a property line cleanout to precisely locate the lower lateral. Storm Drain System The District also has the responsibility to perform annual storm drain maintenance for its member entities. The District has undertaken the task of converting the original paper maps from the cities to an electronic map into the GIS mapping system. In many cases, the storm mapping provided was only a graphical representation of the system and significant field verification of structure locations, and identification numbering, was necessary to have some degree of mapping accuracy. All city storm drain systems have been converted except for the City of Saratoga, which is expected to be completed by the end of The availability of the storm system information in the field is vitally important when determining how to intercept an SSO from reaching a storm drain structure, or if already in the storm system, where to capture it before discharging into a waterway. An example of the storm drain mapping overlaid on the sewer collection system (GIS Sewer Map) is included in Appendix B.1. WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 2 of 12

3 b) Preventive Maintenance Preventive maintenance of the District s sewer system consists of robust cleaning and maintenance programs that are effective and resource efficient. The primary components of the sewer system receiving preventive maintenance include main lines, lower laterals, and pump stations. An effective preventive maintenance program will maintain the integrity of the sewer system and ensure the continuous and safe conveyance of wastewater that should result in a reduced frequency, number, and volume of sanitary sewer overflows (SSOs). The District s preventive maintenance is discussed below through a description of its maintenance programs, cleaning methods, and service call response procedures. The prioritization and scheduling of the District s preventive maintenance program is enhanced by the capabilities of Lucity, which is used to electronically store, track, and manage all operations and maintenance activities pertaining to the collection system. Maintenance history information, asset information, service call data, cleaning schedules, and closed circuit television (CCTV) data are all kept and managed through the Lucity database. The linking of the District s GIS and Lucity database is a powerful feature for field use and provides office staff the ability to graphically represent any collection system and historical maintenance data to help facilitate its analysis. Maintenance Program There are approximately 415 miles of mainline sewer pipe within the District, ranging in diameter from 3 to 39 inches, with nearly 90% of these lines 8-inches in diameter or smaller. An inventory of main sizes within the District is shown in Appendix B.2. The District has approximately 34,500 lateral connections amounting to an estimated 210 miles of lower lateral. A large majority of these laterals are 4 inches in diameter, although some commercial properties have 6 inch laterals. The District owns three small pump stations, two of which pump in tandem to lift wastewater from the Arroyo Del Rancho residential area, while the third serves the separate Alta Tierra residential area. The District s preventive sewer system maintenance program is a very proactive program that is designed to locate, identify, and address problems that may exist in the collection system prior to the occurrence of a failure in the system. It consists of two primary components; maintenance cleaning or servicing and CCTV inspection. These programs were developed to be efficient in terms of resource utilization and effective in the reduction of SSOs by establishing standard cleaning cycles in set geographic areas. By creating large work orders bound within a single geographic region, that also employs the same maintenance crew and equipment, high productivity is achieved through this continuity of and repetitiveness in work activity. Another way efficiency is achieved is by establishing maintenance activity guidelines or procedures for the consistent execution of each maintenance activity. To address maintenance that are considered emergency or asneeded maintenance (service calls), the District has an established procedure in place. WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 3 of 12

4 Mainline Sewer Mainline sewer maintenance constitutes the largest maintenance activity in the District. Based on previous cleaning history and resource capabilities, it was determined that an effective cleaning frequency to be used for standard mainline maintenance was twenty four (24) months. By dividing the District s service area into twenty four (24) geographic zones, or Geozones, mainline cleaning in a particular zone would generally be cleaned during its designated month, or once every two years. There is also a need for more frequent or specialty cleaning routines to address those lines with greater maintenance demands. The special lines include: siphons (two month frequency), and FOG, heavy root problem, and low pressure cleaning areas (one to twelve months). A thirty-six (36) month cleaning frequency is utilized for lines greater than 15 inches and newly replaced or rehabilitated high density polyethylene (HDPE) lines within a CIP Rehabilitation Project. A map of the District showing its 24 Geozones used in standard mainline maintenance is included in Appendix B.3. Lower Lateral - At the same time the Lateral Mapping Program was initiated (mid-2009), a Lateral Maintenance Program was also established. Since lower lateral maintenance cannot occur without a property line cleanout, it was a logical opportunity to perform these two programs simultaneously. Prior to this program, lateral maintenance was merely a reactive program dependent upon receiving service calls from the public. Similar to the concept of Geozone cleaning for mainline maintenance, the laterals are also divided into its own geographic areas. In this case, the geographic areas are based on strategically selected neighborhoods that have experienced historical backups and or SSOs. The prioritization of lateral maintenance in these areas is based on the number and frequency of such events. Due to the lack of history, there is no compelling track record to suggest the most appropriate cleaning cycle. Given that a large number of laterals have not been serviced (by the District) for many decades, it appeared reasonable to establish an initial cleaning cycle of ten years. As with mainline maintenance frequencies, those problem laterals that warrant a higher cleaning frequency due to root intrusion, or structural defect, are placed on a six (6) month cleaning list. If the problem lateral continues to have repeated service calls, or results in multiple backups or SSOs, it is placed on the lower lateral repair list described below. Pump Station - Each pump station has two pumps (lead, lag) with the two tandem pump stations having 11Hp pumps, while the third pump station has 20 Hp pumps. Due to a condition evaluation of these pump stations, each pump station has recently been rehabilitated with new piping, valves, control panels, and manual transfer switches. A weekly inspection and testing is performed on each pump station to verify that all components are working properly. System vitals are monitored remotely and properly alarmed should a failure or fault occur. The location map of the pump stations and the associated pump information is included in Appendix B.4. For routine pump maintenance activities (impeller and bearing replacement, float replacement, control panel light replacement) trained in-house maintenance staff are utilized. More complicated maintenance activities (pump rebuild, motor rewind, high voltage electrical) are contracted out to specialized contractors or to the pump manufacturer. WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 4 of 12

5 CCTV Inspection CCTV inspection of pipeline is plays and important role in this preventive maintenance program in that it is used to confirm cleaning frequencies and methodologies, and determine effectiveness of a cleaning crew. The District s current CCTV inspection program is performed independently of the maintenance cleaning. In other words, the CCTV inspections are performed on dirty lines. This method has some disadvantages related to slower CCTV production and the potential for missed defects. However, the primary advantage is the ability to gage the amount of debris or root build up since its last cleaning to determine if the maintenance cleaning parameters for the pipe is adequate. Another use of CCTV inspection is the post cleaning quality control inspections to document the effectiveness of the cleaning being performed. Cleaning Methods The District utilizes a variety of tools and equipment to perform the required maintenance for mainlines and laterals, depending on the location, expected debris type, and accessibility. The two primary cleaning methods for mainlines are high velocity cleaning (HVC) and power rodding. Performing HVC cleaning requires the use of one of the HVC trucks that are outfitted with a complement of nozzles and cutters that enable the crew to clean a variety of different sizes of pipe as well as remove different types of debris. This method is utilized when access is available for the truck and where there is no history of high cleaning pressures backing up water into a building. The power rodding is performed using the continuous rodder truck. This truck is also equipped with a variety of cleaning tools and used in those areas where a HVC cannot access or where a pressurized cleaning method may cause unintentional toilet burping. For mainlines located in inaccessible easements, the hand rod or chemical root control method is utilized. Chemical root control is performed by a contractor. Whichever cleaning method is used, the estimated quantity and type of debris that was removed by the cleaning operation is documented and entered into the Lucity database. This data along with CCTV inspections are later analyzed to confirm the effectiveness of the cleaning operation used and also to determine whether the cleaning frequency is appropriate for that particular line. Lower lateral cleaning is almost exclusively performed by using an electric power snake/cable, or Spartan. This is a portable unit that is kept on each service truck and is manually rolled to the property line cleanout for use. The maintenance staff hand guides the cable with a 3 or 4-inch blade attachment through the lateral. Strong resistance or impassibility with this effort indicates the presence of an obstruction. If smaller blades are used without success, a CCTV inspection is performed to further investigate the problem. Other than debris remaining on the blades, there is no record available of debris type or amount. Another option for pervasive root intrusion problems is the use of chemical treatment by in-house staff. Service Call Procedure WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 5 of 12

6 The District office is open Monday through Friday from 7:30 am to 4:30 pm except for District holidays. All regular business hour service calls are typically received by the administrative staff or the Operations office. If received by the administrative staff, the call is referred directly to the Supervising Lead Worker or Operations Supervisor. All after hour calls are automatically routed to the Santa Clara County Emergency Radio Communications Center who then directly notifies the District s on-call field operations staff via an assigned mobile phone. The on-call field operations staff is available 24 hours a day during their on-call period and is furnished with a service truck and equipment to facilitate a timely response. A response time goal is a response within 30 minutes for service calls during work hours and within 60 minutes for service calls made after hours. This truck is equipped to address lower lateral blockages and has some spill containment devices to prevent minor SSOs from entering a storm drain inlet or channel. Should the situation require larger equipment and staffing, the on-call person would contact the secondary on-call staff and any additional staff as needed. The additional staff would obtain the required equipment from the District yard prior to travelling to the emergency site. The circumstances of the call-out and the corresponding activities executed are properly documented and recorded in Lucity as a service call and work order. Should the service call involve a Category I SSO, the Operations Supervisor would be contacted to make the necessary notifications to California Office of Emergency Services (OES). For response procedures reference the Sewer Backup Response Guide and Sewer Overflow Response Guide in Appendix C.3 and C.4, respectively. Some additional requirements are shown on these Guides that are obligations agreed to in the River Watch Agreement. c) Rehabilitation and Replacement The rehabilitation and replacement of the collection system is addressed through the District s Capital Improvement Program (CIP) and is the largest spending component of the District s budget. Due to the average age of the District s system at around 50 years old (the oldest pipe is nearly 100 years old), preventive maintenance alone is insufficient to ensure the long term viability of the system. The three basic elements needed to develop an effective Capital Improvement Program is to inspect and assess the system condition, perform a risk based prioritization of the system, and to develop a prioritized repair and rehabilitation project plan. The purpose of a sanitary sewer rehabilitation and replacement plan is to identify and prioritize system deficiencies and implement short and long-term repair or rehabilitation actions to address each deficiency. Some deficiencies can be readily addressed with a point repair, or a single sewer line replacement, while other deficiencies may require a major CIP project rehabilitating miles of sewer main, laterals, and manholes. Two recently added components of the rehabilitation program includes the Private Lateral Replacement Program (PLRP) which was created to satisfy the Supplemental Environmental Project (SEP) obligation of the River Watch Agreement, and a second obligation to repair pipelines in close proximity to surface waters. WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 6 of 12

7 Inspection and Condition Assessment Inspection Practically all inspections of the collection system piping is performed using CCTV. Some inspections of other system components may be performed visually, while more detailed pipe and manhole inspections may require the use of an infrared, sonar inspection, or possibly destructive inspection methods. The inspection method used is dependent upon the type and location of the structure being examined, and the purpose for which the examination is being made. The information obtained through inspection provides invaluable information that helps staff determine whether to increase the amount of maintenance effort, or to help define the scope of repair or rehabilitation efforts. The District has a modern CCTV van that uses state of the art digital video equipment and conducts pipe and manhole inspections on a daily basis. The CCTV van is equipped with motorized main line cameras, easement or lateral (push) cameras, and a pole camera. The motorized main line camera has a complement of wheel sizes and types to allow it to traverse through pipe of varying grade, condition, and material type from 6 to 15 inches in diameter. Inspection of larger pipe requires the rental of a larger camera, or contracting the inspection effort with a consultant. Nearly all of the CCTV inspection work for main line is performed on a planned schedule and is conducted within 42 separate drainage subbasins, which was developed as part of the District s Strategic Basin Rehabilitation Plan (Carollo, April 2000). Lines which experience an SSO, prove to be difficult to clean, or are suspected to have some abnormality, are televised as necessary to determine the cause of the problem. The complete cycle for televising the entire District s main line inventory is currently on a ten to twelve year period. The importance of up-to-date inspection video and the resultant condition assessment, dictates that a more frequent CCTV cycle is necessary. Implementation of a more aggressive CCTV inspection program to reduce the inspection cycle to eight years was initiated in early 2012 through reassignment of maintenance staff and the purchase of a specialized service truck for the Lateral Maintenance Program. The reduction of the CCTV inspection cycle to eight years is also one of the obligations of the River Watch Agreement that must be satisfied within the agreement period. Condition Assessment The condition assessment of pipeline and manholes is a major component in assigning risk to its potential failure and the prioritization of the District s CIP projects and annual sewer repair program. The condition assessment is performed during CCTV inspection by observing structural and maintenance deficiencies utilizing standardized condition rating guidelines. The District utilizes Flexidata software as part of its CCTV program and NASSCO s Pipeline Assessment and Certification Program (PACP) coding system for mainline inspections. The use of PACP is becoming the universal standardized coding system throughout the industry. Although the sewer laterals are not currently rated as part of the CCTV program, NASSCO is developing a lateral rating system, or LACP. The PACP defect coding from Flexidata is exported into Lucity where the overall rating of each pipe is calculated. The numerical rating of each pipe within the collection system is then translated into a simplified condition ranking (very significant, significant, moderate, fair, and good) allowing for the prioritization of needed repairs. It WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 7 of 12

8 should be noted that the very significant or significant rankings do not necessarily imply that the pipe faces imminent collapse or requires immediate repair. In fact, some agencies have utilized failure time estimates in conjunction with these rankings: very significant (0 to 5 years), significant (5-10 years), moderate (10-20 years), fair (20+ years), good (50+ years). Expedited CCTV inspection and assessment for those lines within 250 feet of surface waters is one of the obligations of the River Watch Agreement. This heightened priority is meant to focus attention to those lines that have increased potential to discharge sewage into a waterway. The inspection and assessment is categorized as those lines with adequate CCTV (up to 10 years prior to 8/29/12) and those that are outdated and need to be updated (precede 8/29/02). See the Repair and Rehabilitation section below for the significance of this obligation. Risk Assessment The determination of repair priority, other than in imminent failure or emergency situations, can be subjective in nature. To provide a more objective approach to prioritization, the District has tasked RMC Water and Environment to develop a risk-based prioritization model to help in the District s decision making. This prioritization process is based on guidelines recommended by the National Association of Clean Water Agencies (NACWA) in their publication Implementing Asset Management: A Practical Guide and quantifies risk as a product of the consequence of failure and likelihood of failure. The factors used in consequences of failure are primarily centered around the impacts to the community and environment, while the likelihood of failure factors generally involve system condition, maintenance history, and hydraulic capacity. It should be noted that the model provides a significant element in the prioritization process, but that it is not the only criteria to be considered. Other factors (project scoping, timing, budget allocation, resource availability, infiltration and inflow susceptibility, etc.) must still be considered when formulating a final prioritization order. The risk-based prioritization study was completed in October 2010, portions of which are shown in Appendix B.5. There is a current effort in FY to update this risk based prioritization model to reflect current data and possibly some additional likelihood of failure parameters, or changes in weighting used for a number of parameters. Repair and Rehabilitation The repair and rehabilitation of the collection system, is the largest spending component of the District s budget. Due to the average age of the District s system at around 50 years old (the oldest pipe is nearly 100 years old), the repair and rehabilitation as addressed through the District s Capital Improvement Program (CIP), is absolutely essential for the long term viability of the District s sewer system. The District has consistently budgeted an aggressive rehabilitation and repair program. Within the last five fiscal years (FY 09 13) the District has expended approximately $6.6 million and $2.0 million, for rehabilitation and repair projects, respectively. In the current Five-Year CIP (FY14-18) it is expected that the expenditures will increase to $15.0 and $3.0 million, respectively. WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 8 of 12

9 Some of the proposed increase in spending is due to the District s obligation associated with the River Watch Agreement to increase the priority of repairs for those pipelines that are within 250 feet from surface waters and have a PACP rating of 4 or 5. As stated above, this prioritization change is meant to focus attention to those lines that have increased potential to discharge sewage into a waterway. These repairs are required to be completed in two stages; for the adequate CCTV category, repairs are required to be complete by 8/29/14, and for the outdated category repairs are to be completed by 8/29/16. The PLRP requires a smaller initial investment and focuses on the repair of the private (upper) laterals. Although this is not part of the District s collection system, there is evidence that a significant amount of inflow and infiltration (I&I) originates in the upper lateral. Reduction in I&I will reduce the hydraulic load on the District s collection system and the San Jose-Santa Clara Regional Wastewater Facility. d) Staff Training and Certification The District s training program covers a number of areas involving, or associated with wastewater collection systems and serves to develop and maintain highly qualified, knowledgeable, and dedicated staff. This training is provided through a variety of modes (self-study, seminars, conferences, on-the-job, etc.) and begins from the first day on the job and continues regularly thereafter. Since safety training constitutes a significant portion of the total training received each year, the District utilizes the services of a safety consultant to monitor, track, and provide this training. A majority of safety training is provided as an on-line course. The CWEA Technical Certification Program provides certification in a variety of wastewater disciplines to promote and enhance the education and effectiveness of the wastewater professional. The District encourages its maintenance staff to obtain CWEA certification to demonstrate their level of competency in the area of collection system maintenance. By providing adequate staff training and establishment of certain grade level requirements as a condition of career advancement, the District reinforces the importance it places on certification. Training Frequency and Subject Matter Although all ongoing training is considered to be important and necessary, the initial orientation training for maintenance staff is especially important to establish a sound knowledge base for equipment, safety, and maintenance procedures. Maintenance staff is provided many training opportunities in a number of subject matter pertaining to collection system operation and maintenance. Within the first year of hire, all Maintenance Worker Trainees are enrolled and must pass the Office of Water Programs, CSU Sacramento (Ken Kerri) Operation and Maintenance of Wastewater Collections Systems Volume I and II courses. These individuals must also indoctrinate themselves with basic safety and collection equipment operation by studying equipment procedures, training movies, and in the field WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 9 of 12

10 training by an experienced maintenance staff, prior to fully participating on work crews. On a regular basis, safety training is received weekly through tailgate safety meetings, webbased or instructor led safety meetings. A less structured, but valuable training is received on-the-job through mentoring by senior staff. There are also a number of seminar training opportunities provided by local CWEA, at regional or state CWEA conferences, and through CSRMA. There is a wide variety of training subject matter that is provided or offered for maintenance staff. To maintain brevity, only a few sample training topics are shown for major subject areas. Wastewater Collection System Operation and Maintenance Sewer Cleaning Equipment O & M Collection System Toolbox CCTV Operation and Maintenance NASSCO/PACP Certification SSO and Backup Response Pump Station O&M Electrical Basics and Troubleshooting Collection System Management Lucity Work Modules (CMMS) GIS Mapping Global Positioning System (GPS) Safety Confined Space Lockout/Tagout Traffic Safety CPR/AED Hazmat Ergonomics Personnel and Other Supervision and Management Training Communication MS Office Suite CWEA Certification Achieving certain levels of CWEA Certification is required for promotion to a higher maintenance positions. In the Maintenance Worker Series, the Maintenance Worker Trainee is required to have a CWEA Grade I Certification before promotion to Maintenance Worker I, and a Maintenance Worker I is required to have a CWEA Grade II Certification before promotion to Maintenance Worker II. WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 10 of 12

11 In line with the District s emphasis on certification, all maintenance staff other than the Maintenance Worker Trainee, are certified in Collection System Maintenance at a Grade 2 or higher level. Currently, nearly half of the maintenance staff has attained a Grade 3 or 4 certification level. The District further encourages maintenance staff by offering pay incentives to those wishing to exceed the certification grade requirements for their position, including the acquisition of the Plant Maintenance Certification. Staff CWEA certifications are presented in Appendix B.6 e) Maintenance and Contingency Equipment The District maintains a host of equipment for both routine maintenance and for contingency or emergency operations. For specific emergency situations, the District has several types of equipment stored at the District yard and are kept in a prepared state for immediate service. Included in this discussion is the availability of parts, supplies, and contractor services. A list of the District s primary maintenance vehicles and emergency equipment is included in Appendix B.7. Emergency Equipment The District relies on the use of its maintenance fleet in emergency situations. The primary equipment available includes two (2) combination HVC/Vacuum truck units and one (1) HVC jetter truck that are outfitted with a complement of nozzles and cutters that enable these trucks to be used to clean a variety of different pipe sizes and remove different types of debris blockages. The District has one (1) continuous rodder truck that is also equipped with a variety of cleaning tools. For sewer laterals the District has four (4) service trucks each equipped with heavy duty power snakes that are utilized for customer service calls and performing preventive maintenance on the lower laterals. These service trucks also carry spill containment mats and sandbags to contain an SSO and prevent sewage from entering storm drains. In an emergency where sewage bypass pumping is required, the District has several pump options depending upon the particular situation and flow requirements. These pumps include a trailer mounted 1,500 gpm 6-inch self-priming pump with a capacity of about 2.1 mgd, four smaller portable trash pumps ranging from 3-inch to 4-inch with capacities of approximately 400 gpm. Associated suction and discharge hoses with Camlock type connectors are kept with the pumps. For emergency power supply to run any of the District s three pump stations, a trailer mounted 60 kw generator is available for service through a forty foot cable with quick connect plugs and use of station mounted manual transfer switches. The District has an informal agreement with the City of San Jose maintenance department to assist with equipment. This was utilized several years ago when there was a significant SSO event. Replacement Parts and Supplies WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 11 of 12

12 The District maintains an inventory of replacement parts for each of the pump stations and a modest supply of material for the repair of pipe and manholes. Although each pump station has more than adequate capacity to handle incoming flow with just one of the two pumps installed at each station, spare pumps and significant components (impellers, bearings, etc.) are kept on hand. Since the repair of pipelines, other than manhole frame replacements, are performed by outside contractors, the District maintains a small supply of clay and plastic pipe of various diameter and their associated couplings should they be needed on short notice. Emergency Repairs Repairs to pipelines and manholes, or electrical issues at the pump stations, are typically performed by outside contractors. These contractors are on an on-call open service contract with the District to provide emergency and routine service when requested. Although these contractors have the capacity to perform most all of the emergency repairs normally encountered, should an extraordinary event take place that requires a substantial effort, a list of locally available large contracting companies and vendors would be used to solicit construction services. WVSD Sewer System Management Plan Section IV Operation & Maintenance Program Pg 12 of 12