TO: Public Works Commission FROM: Robyn Mattison, Jim Pardy, and Shawn Wilson DATE: June 30, 2017 RE: Water Renewal Fund Capital Projects

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1 TO: Public Works Commission FROM: Robyn Mattison, Jim Pardy, and Shawn Wilson DATE: June 30, 2017 RE: Water Renewal Fund Capital Projects MAJOR PROJECTS, INITIATIVES, CURENT ISSUES Clean Water: Major Projects Status Water Renewal Facilities Plan A team led by Brown & Caldwell is performing Water Renewal Facilities Plan updates. The last plan was developed in The planning effort is a three phase process which includes: 1. Baselining Existing Assets, Identifying Constraints, and Updating Long Term Projections 2. Developing and Evaluating Solutions to Close the Gap between the Existing Assets and the Projections 3. Prioritizing and Implementing Solutions The project team has completed Phase 1 and is proceeding with Phase 2 which will continue through Related planning work includes: A task order is underway with HDR to update the facility plan for the Twenty Mile South Biosolids Application Site (TMSBAS). HDR has completed a farm baseline that will support the Facilities Planning efforts with Phase 1. The remainder of the farm facility plan work will align with the ongoing water renewal fund facilities planning efforts. A new task order is underway with HDR to provide continued regulatory guidance throughout the NPDES permit re-application process and to support developing a water reuse permit for Lander Street potentially discharging into Farmers Union Canal. This work will be coordinated with the outcome of Phase 2 of the Water Renewal Fund Facilities Planning when long term program direction is defined. Temperature Mitigation Studies

2 Staff continues to work with IDEQ and the EPA in developing temperature mitigation strategies. West Boise WRF Phosphorus Removal The contract for the West Boise Phosphorus (P) Removal Project was completed and closed in Jan 2016 (Enhanced Biological Nutrient Removal, or EBNR). As follow-up, additional design features were added to improve performance of the fermenter mixing system, which proceeded with construction in Sept The fermenter mixing system modifications are currently underway and expected to reach completion in July Operation of the EBNR process has improved and stabilized since July EPA approved the City s request for a major NPDES permit modification to adjust the West Boise interim P limits from a seasonal average of 600 µg /L Total Phosphorus (TP) to an annual average of 2,800 µg /L TP. The resulting calculation of the combined average from May 2016 through February 2017 is currently 1,375 µg /L TP and is expected to meet the annual limit of 2,800 µg /L TP. The Operations Division has been effectively producing struvite which is a critical component to comply with the TP discharge limits. Decreased performance of the Struvite Production Facility (SPF) quickly affect facility performance and impact effluent TP discharge concentrations. A significant and innovative process modification was completed by internally combining two separate treatment processes into a single blended feed to the SPF in mid-september The blended flows improve TP recovery (as struvite) which has also improved the consistency of the final struvite in the heat treatment process (Rollomixer). The process change was also able to utilize the available ammonia in the belt filter press (BFP) filtrate and eliminate the purchase of commercial aqueous ammonia used in the phosphate-enriched filtrate (PFLT) struvite reactors. The struvite heat treatment system required to satisfy EPA s 503 regulations for pathogen reduction in biosolids has been able to nearly match the struvite production rate. Final implementation of the struvite disposition contract is being negotiated with the technology provider, Multiform Harvest, Inc. (MHI). The City released six (6) full semitrailer loads of struvite, which met the Class A criteria, to MHI in February 2017 for processing as a commercial fertilizer product. West Boise Capacity Improvements: Anaerobic Digestion and Dewatering The project focus areas are biofilter expansion to meet current needs, reviewing the sludge dewatering system and investigating limitations in anaerobic digestion capacity. Bids for a new biofilter, thickened primary sludge pumping improvements, and digester piping modifications were received in June Work is expected to be completed in the fall of Dewatering evaluations are complete resulting in rehabilitation of the existing Belt Filter Presses with new and factory refurbished belt rollers. Belt Filter rehabilitation is projected to be complete by January New digester design is delayed until upgrades and inspection of the existing digesters are complete. Current digester work includes piping modifications to allow parallel flow operation to all 3 digesters, cleaning and condition assessment of the existing digesters and optimization Page 2 of 5

3 of the existing digestion capacity. HDR will perform condition assessments of the digesters starting this summer with the final inspection completed in Spring Next phase decisions will depend on the condition of the existing digesters. Dixie Drain Phosphorus Removal The Dixie Drain Phosphorous Removal Project construction was completed in 2016 and is fully operational and meeting our compliance requirement of 25 pounds per day of phosphorus. Minor upgrades to the facility include a mechanical screen cleaning system which is currently being fabricated by the manufacturer with installation anticipated in Fall Revegetation of disturbed areas along the Dixie Drain, which will help with erosion control and temperature in the drain, will begin in October. The contractor is currently completing a list of repairs identified in the 1-year warranty walkthrough. Additional improvements to advance operations and efficiency have been identified and are underway by city staff. In June of this year, the Association of Idaho Cities (AIC) presented the City of Boise a City Achievement Award for the Dixie Drain Phosphorus Removal Facility and its role in innovation. Lander Street WRF Plant-Wide Improvements The City s current NPDES permit for Lander Street (LS) requires low effluent TP concentrations and the schedule of compliance must be completed no later than September 1, Critical projects at Lander Street to meet the TP schedule of compliance and to replace critical aging infrastructure were identified from the Facility Plan and have proceeded into conceptual design. A CIP budget was approved beginning in FY17. Work during the first 5 years is expected to include site utilities improvements, new preliminary treatment, new effluent filtration to achieve the low effluent TP limits, and Ultra-violet light (UV)disinfection improvements. Public Works Engineering defined the goal to complete construction in FY21 to allow one full year of operation before the NPDES compliance date. All Lander Street improvements are expected to cost up to $80M over the next 10 years, with up to $58M before FY22. Engineering design is contracted to a team consisting of CH2M with Brown and Caldwell. The City selected McAlvain as the Construction Manager / General Contractor (CM/GC) for pre-construction and construction phase services. The Preliminary Engineering Report will be prepared by the design team, with input from the CM/GC, this Fall with Idaho Department of Environmental Quality review and approval anticipated by the end of the calendar year. Combined Heat and Power (CHP) or Renewable Natural Gas (RNG) and Food Waste Receiving This project anticipates constructing facilities to collect food waste and brown grease for methane production. The methane gas produced will either be used by generators to create electricity or will be cleaned for direct use. A CIP budget was not authorized for FY17, nor is one requested for FY18 due to cash flow constraints in the water renewal fund. Page 3 of 5

4 Clean Water: Issues & Strategies Currently the Clean Water Section has 11 FTEs, including two control system techs that were transferred from the Operations Division. The last workload projection estimated between 13 and 18 FTEs will be required through 2018 to complete planned projects. The current strategy of hiring consulting services to make up the difference between City staff and required staff will continue. In addition to the projects discussed above, the projections include near-term future projects being driven by NPDES permit requirements: filtration at West Boise for additional P removal, and effluent temperature mitigation for both WRFs. Future project needs will be updated when the Facilities Planning plant capacity assessments are completed. In December 2013 two additional positions for a process controls engineer and a process controls programmer were approved by the City Council. Only 1 was filled, and in the summer of 2016 the other position was forfeited to gain a full-time instrument technician at LS. The controls Engineer II position was filled in July 2015, and a large amount of work, some previously unrecognized, has been identified: creating, organizing and updating wiring drawings for maintenance troubleshooting; updating control standards; establishing electrical standards; developing electrical distribution models for both WRFs that are necessary for arc flash analyses; supervising two control systems technicians; and managing or providing electrical and controls support on CIPs. The intent, with the addition of these employees and the organizational changes is to maintain and monitor the automated plant controls in a systematic manner that will reduce the incidents of controls failure or of troublesome controls being overridden, and to plan for systematic technology upgrades. Staff has requested city council approval of an additional Controls Engineer II position in FY18 to better accomplish these goals. Sewer Design: Collection System Projects Status Small Diameter Sewer Pipe Rehabilitate/Replacement Program In accordance with the small diameter pipe rehabilitation/replacement program, 45 segments were identified to be rehabilitated in To date 24 of the 45 segments have been completed. Construction is on schedule. Estimated expenditures to complete this work is $1,000,000 in which budget is available. Sewer Design: Issues & Strategies A vibrant construction climate is resulting in less contractors bidding on projects and the cost of work is rising. In addition, construction companies appear to be struggling to keep and retain laborers and equipment operators. In response to this, some companies are increasing pay and benefits in an effort to attract and retain skilled workers. This also is contributing to higher bid prices. In 2018 the Engineering Department will package the rehabilitation projects into two projects instead of three. Reasoning is staff believes the larger packaged project will create more interest among contractors. Page 4 of 5

5 Large Diameter Pipe Rehabilitation Program Three large diameter sewer pipe point repairs were completed during the spring. Projects were successful in eliminating significant infiltration found within these segments. No additional large diameter projects are scheduled for this year. Inflow and Infiltration (I/I): Issues & Strategies High river flows this spring provided an opportunity to do sanitary sewer flow monitoring in hopes of identifying inflow and infiltration sources. Several weeks of data were collected and are currently being analyzed, results of which will be used to prioritize future mainline and manhole rehabilitation projects. Page 5 of 5