INFLOW AND INFILTRATION REDUCTION STRATEGY

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1 INFLOW AND INFILTRATION REDUCTION STRATEGY ANNUAL REPORT MARCH 31, 2016

2 Table of Contents Highlights of program activities and accomplishments Inflow and Infiltration Reduction Inflow and Infiltration Reduction Progress Continuous Investigations, Operation and Maintenance Programs Carried out by Local Municipalities in Private Initiatives Aurora Vaughan Ongoing Inflow and Infiltration Reduction Initiatives Servicing Incentive Program Collaboration and Partnership Regional CCTV Inspection Sanitary Sewer Evaluation Survey (SSES) Activities Lateral Sewer Rehabilitation Pilot Projects Short-Term Mini-Basin Monitoring Long-Term Inflow and Infiltration Audit and Flow Monitoring Program Appendix 1 Quantified Catchments for Inflow and Infiltration Reduction Appendix 2 Examples of Communication Material/Notices used during SSES Activities Inflow and Infiltration Reduction Strategy Annual Report

3 HIGHLIGHTS OF PROGRAM ACTIVITIES AND ACCOMPLISHMENTS 2015 Highlights of the accomplishments and key program activities completed through 2015 include: An approximate reduction of 1.18 MLD was achieved (3.0% of the total inflow and infiltration reduction target) 35 km of Regional sewer were inspected by CCTV 420 km of local municipality sewer were inspected by CCTV 829 m of local municipality sewer was relined 68 roof downspout connections to the sanitary sewer system were identified and removed 3199 maintenance holes were inspected and 166 were repaired $5.1 M was spent by the Region on activities related to inflow and infiltration reduction at the Regional and local municipal level. The local municipalities spent approximately $3.5 M on inflow and infiltration related activities Long-term flow monitoring: o Data was collected and analysis is ongoing from 248 flow monitoring sites o 241 meters were installed in 2014 and 2015 o Data was collected and analysis is ongoing from 70 York Region and partner rainfall monitoring sites Developer-funded investigation and remediation activities have been completed as follows: o Aurora, with an estimated reduction of 0.1 MLD o Vaughan, with an estimated reduction of MLD Inflow and Infiltration Reduction Implementation of the Inflow and Infiltration Reduction Strategy began in March Achievements between then and 2014 were summarized in Inflow and Infiltration Reduction Strategy Reports submitted annually to the Ministry between 2012 and A summary of inflow and infiltration reductions achieved in 2015 is presented in Table 1.1. Further detail is provided in Appendix 1. Inflow and Infiltration Reduction Strategy Annual Report

4 Table 1.1 Municipality Inflow and Infiltration Reductions from 2015 Remediation Activities Reduction Achieved (MLD) Total of Area Municipalities Description Vaughan (Private) Downspout disconnection and mainline sewer repairs Aurora (Private) Downspout disconnection Markham (YR) Maintenance hole repair Markham (YR) Box culvert repair Total of Private Initiatives Total York Region Grand Total Inflow and Infiltration Reduction Progress A total inflow and infiltration reduction of 1.18 MLD was determined through regression analysis and other methods where flow monitoring data was not available. Table 1.2 shows the original timeline for Inflow and Infiltration Reduction Strategy goals. Inflow and Infiltration Reduction Strategy Annual Report

5 Table 1.2 Reduction Targets and Required Activities Timeline Activity Establish Baseline Flows Enhanced Program Development Municipal Remediation Project Implementation Measure Success of Remediation Projects Refine Targets for I/I Reduction Ongoing Capital Projects & Flow Reduction Achieve Up to 25% of Target Reduction Achieve % of Target Reduction MOECC Annual Report Strategy Update to MOECC A total of 25 per cent of the target reduction was originally slated to occur by the end of To date, the Region has achieved a reduction of 9.6 MLD in the YDSS which is 24 per cent of the overall 40 MLD goals. Therefore, the Region is on track to meet the interim targets specified in the Inflow and Infiltration Reduction Strategy. Table 1.3 shows the reductions reported to date. Year Table 1.3 Yearly Inflow and Infiltration Reductions Reduction (MLD) Total 9.60 MLD Inflow and Infiltration Reduction Strategy Annual Report

6 3. Continuous Investigations, Operation and Maintenance Programs Carried out by Local Municipalities in 2015 Reactive and corrective inspection, cleaning and repair are being performed on priority assets deemed to be critical for rehabilitation and replacement. Local municipality CCTV and other investigations and costs for 2015 were as follows: Aurora 27.2 km of mainline sewer inspected at a cost of $102K. East Gwillimbury 29.3 km of mainline inspected. 412 maintenance holes inspected. King Township 188.5m of mainline inspected. Markham 50 km of mainline inspected at a cost of $391K. 56 smoke and dye tests completed at a cost of $76K. 582 maintenance holes inspected at a cost of $45K. Newmarket 23 km of mainline sewer inspected. 115 maintenance holes inspected. Richmond Hill 114 km of mainline sewer inspected at a cost of $177K maintenance holes inspected. Vaughan 167 Km of mainline inspected at a cost of $435K. Whitchurch-Stouffville 9.4 km of mainline inspected. Local municipal rehabilitation work carried out in 2015 included: Aurora 124 maintenance holes repaired at a cost of $130K. King Township 8 m of mainline sewers repaired. Markham 421 m of mainline sewers repaired at a cost of $91K. 42 maintenance holes repaired at a cost of $77K. Newmarket 400 m of mainline sewer repaired at a cost of $370K. Local municipalities have continued to inspect and repair lateral sewers in 2015 including: Aurora 717 laterals inspected at a cost of $89K. 45 laterals repaired at a cost of $261K. East Gwillimbury 588 laterals inspected, with 7 repaired. Markham 1,450 laterals inspected at a cost of $208K. 75 laterals repaired at a cost of $457K. Newmarket 233 laterals inspected, with 5 laterals repaired. Inflow and Infiltration Reduction Strategy Annual Report

7 Richmond Hill 103 laterals inspected at a cost of $46K, with 18 laterals repaired. Vaughan 780 laterals inspected at a cost of $185K, with 50 laterals repaired at a cost of $322K. Local municipalities have continued to identify and disconnect direct connections in 2015 including: Markham 43 connected roof downspouts identified and disconnected. Vaughan 25 connected roof downspouts identified and disconnected. These activities have not been captured in the 2015 Annual Report and will be reported in next years report. Post flow monitoring is still ongoing. 4. Private Initiatives Private initiatives include developer-funded inflow and infiltration reduction pilot projects where developers enter into a tri-party agreement with the Region and respective local municipality to undertake inflow and infiltration reduction work in exchange for advancement of servicing allocation. Five agreements have been executed to date in the following local municipalities: Aurora Markham Newmarket Richmond Hill Vaughan Inflow and infiltration remediation work performed in 2015 was as follows: 4.1 Aurora 17 commercial property roof downspouts were disconnected from the sanitary sewer. 1 sedimentation pond overflow was disconnected from the sanitary sewer. The total estimated reduction was 0.1 MLD Inflow and Infiltration Reduction Strategy Annual Report

8 4.2 Vaughan 12 roof downspouts disconnected from residential properties. 22 mainline sewers were repaired through point repairs, such as grout injections or CIPP spot repairs. The total estimated reduction was MLD. 5. Ongoing Inflow and Infiltration Reduction Initiatives 5.1 Servicing Incentive Program In 2015, the Region continued to implement SIP for new development. The program promotes inflow and infiltration reduction through providing additional servicing capacity assignment to developers in exchange for higher standards in construction and inspection of sewer works. Examples of construction standards in SIP include: Sanitary sewer pipes shall be comprised of PVC DR 35 (or better) based on pipe depth, and shall be installed with bell and spigot gasketed joints. C900 (100mm to 300mm) or C905 (340mm to 600mm) PVC pipe (or concrete pressure pipe) will be specified in areas of high water table or where the sewer is greater than 8.5 meters below grade. Benefits will be proven by flow monitoring of new development for a period of at least eight months and the following benchmarks satisfied: Maximum instantaneous extraneous (RDII) flow allowance shall be 0.12 L/s/ha, under a 25-year event Maximum groundwater infiltration (GWI) allowance shall be L/mm diameter per 100 m of sewer pipe per hour, which is more stringent than OPSS-410. In 2015, the Town of East Gwillimbury incorporated the SIP program requirements within their Sustainable Development Incentive Program Implementation Guidelines (SDIP). In addition, one landowner s group in Aurora is now participating in the SIP program. Inflow and Infiltration Reduction Strategy Annual Report

9 5.2 Collaboration and Partnership The Region participated in the 1st annual Water and Wastewater Development Engineer and Inspectors Knowledge Sharing Workshop, which was held between the Region and the local municipalities in fall of Key items discussed at the workshop included: Overview of the SIP program Sanitary Sewer System Inspection, Testing and Acceptance Guideline Unacceptable inflow and infiltration in new subdivisions SIP and the Town of Aurora process Long-term Inflow and Infiltration Reduction Strategy CCTV Inspections; construction inspections, flow monitoring; design guidelines, standards and by-laws; coordination with building department 5.3 Regional CCTV Inspection The Regional CCTV program for 2015 included inspection of 35 km of trunk sewer. 5.4 Sanitary Sewer Evaluation Survey (SSES) Activities Once mini-basins are identified as being sources of significant inflow and infiltration, SSES programs are developed and executed by York Region. SSES programs include collection of condition information from existing data, identification of additional inspection requirements, development and implementation of planned inspections and data analysis. These inspections provide crucial data for pinpointing the sources of inflow and infiltration. This information will also provide the basis for the development of rehabilitation actions. The Region has continued with SSES activities in 2015 in Vaughan (Kleinburg), King (Nobleton), and Richmond Hill (Pomona) to identify sources of inflow and infiltration. These activities have included smoke and dye inspection, household drainage surveys and groundwater investigations. Smoke inspections in Kleinburg, Richmond Hill and Nobleton identified a number of deficiencies to be prioritized for remediation, and recommended that dye inspections be performed to confirm the presence of potential direct connections that were identified. For the most part, dye inspections can confirm direct connections to the sanitary sewer system, where an earlier visual inspection or data review has identified a probability that there is a direct connection to the sanitary sewer. Inflow and Infiltration Reduction Strategy Annual Report

10 Figure 1.1 Smoke Inspection Observation Stakeholder engagement and detailed communication is an essential aspect of SSES, encompassing everything from the review, feedback and approval process of communication material by the Region and the local municipality; up-to-date scheduling and updates to project managers, local municipal operations, emergency services, and regulatory agencies; and fielding questions and comments from residents. Throughout the SSES projects a two-stage proactive notification protocol was undertaken as follows: The Notice of Project Commencement was reviewed and approved by the Region prior to delivery to all residents within the designated testing areas at a minimum of one week in advance of any testing activities. See Appendix 2 for sample notices and door hangers. Prior to each day of testing, the Region and local municipality s operations department, emergency services and the Ministry were notified via , informing them of the specific locations being tested each day and any significant traffic diversions or disruptions, and in the case of dye inspections, a list of local waterways which could potentially be affected. 5.5 Lateral Sewer Rehabilitation Pilot Projects In partnership with local municipalities, the Region has implemented a pilot project for the repair of sewer laterals in the Towns of Aurora, East Gwillimbury, Georgina, Newmarket and the City of Vaughan. The project was designed to inspect and repair lateral sewers. Inspection activities were completed in 2014 and in 2015, and repairs were initiated to address identified deficiencies. Inflow and Infiltration Reduction Strategy Annual Report

11 6. Short-Term Mini-Basin Monitoring One of the outcomes of the Infiltration and Inflow Audit and Flow Monitoring Program is the ongoing identification of audit basins where measured inflow and infiltration exceeds performance thresholds. When non-performing audit basins are identified, a program of SSES and mini-basin monitoring are initiated. The Region continued targeted or mini-basin monitoring of five flow monitoring sites in 2015 which included: 3 mini-basin areas identified with high inflow and infiltration in Nobleton 1 mini-basin area in Georgina to confirm flow and pipe network connectivity 1 mini-basin area in Vaughan for post-rehabilitation monitoring. 7. Long-Term Inflow and Infiltration Audit and Flow Monitoring Program The ongoing Inflow and Infiltration Audit and Flow Monitoring Program will assess existing inflow and infiltration in local systems as well as monitor new development areas over time. Flow and rainfall data collected on a long-term basis will help determine inflow and infiltration volumes for audit and reporting purposes as well as identify issues with system performance and remediation opportunities. In addition, the data has been used to support the development of the all-pipes hydraulic model which is used for growth management, asset management and planning purposes. This program provides the near real-time data necessary for auditing flows throughout the Region, identifying sources of inflow and infiltration, confirming reductions, minimizing system risk, and maximizing system capacity by fully leveraging existing infrastructure. The program is in its 2 nd year of phase three, characterizing flows from 218 Audit Basins through collection of data at 248 flow monitoring sites and 41 Region rain gauges. Additionally, the Region has access to data from 29 rain gauges through partner agencies. Data from these stations is uploaded to the web-based data management application FlowWorks. The application also transfers the collected flow and rainfall data into the Region s Data Warehouse. Region staff can extract data from the Data Warehouse using a custom-designed data management tool which allows users to easily transfer data into analysis tools. Figure 1.2 presents the functionality of the data management tool. Figure 1.3 provides the locations of flow monitors and rain gauges as seen within the FlowWorks application. The Region also uses FlowWorks to share data with local municipalities. Inflow and Infiltration Reduction Strategy Annual Report

12 Figure 1.2 Data Exchange and Data Warehouse Technical Infrastructure and Solution Architecture Figure 1.3 Map-based Network Overview of Flow Meter and Rain Gauge Locations as appears in FlowWorks Equipment was installed from 2013 to 2015 and has an estimated lifespan of at least five years. As a result, the Region will not need to start procurement of replacement equipment until sometime after Inflow and Infiltration Reduction Strategy Annual Report

13 The Region maintains 41 rainfall gauges and has access to data from a further 29 rainfall gauges, through partnerships with other agencies including the Toronto and Region Conservation Authority (TRCA), Lake Simcoe Region Conservation Authority (LSRCA), Town of Richmond Hill and the City of Markham. Consideration was also given to augmenting the Region s rain gauge network with radar data to increase the resolution of the existing rainfall data. The review concluded that the current locations provide sufficient rainfall coverage to accurately perform inflow and infiltration calculations. This review will be revisited in 2018 as technologies and processing tools advance. Figure 1.4 presents the current locations of audit basin flow monitors and rain gauges. Inflow and Infiltration Reduction Strategy Annual Report

14 Figure 1.4 Inflow and Infiltration Audit and Flow Monitoring Program map showing flow monitor and rain gauge locations Inflow and Infiltration Reduction Strategy Annual Report

15 Appendix 1 Quantified Catchments for Inflow and Infiltration Reduction Inflow and Infiltration Reduction Strategy Annual Report