ALBEMARLE COUNTY SERVICE AUTHORITY

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1 AGENDA TITLE: Rivanna Water & Sewer Authority (RWSA) Monthly Update STAFF CONTACT(S)/PREPARER: Gary O Connell, Executive Director AGENDA DATE: February 16, 2017 CONSENT AGENDA: Informational ATTACHMENTS: None BACKGROUND: This report continues the monthly updates on the Rivanna Water & Sewer Authority (RWSA) projects and Board meetings. Below are some updates on RWSA projects and issues, including updates from the January 24, 2017 RWSA Board Meeting. Drinking Water GAC (Granular Activated Carbon) Project To meet new water quality standards, the RWSA has Granular Activated Carbon (GAC) advanced filtering projects underway at all the five (5) water treatment plants. In addition, water plant improvements, upgrades, and rehabilitation are underway at the South Fork, Crozet and Observatory Water Treatment Plants (WTPs). The anticipated completion dates for all the water treatment plant projects is December, South Rivanna WTP - Construction of additional clearwell storage; installation of a chlorine contact tank; replacement of the lime feed system; upgrades to the filter underdrains and backwash system; replacement of the filter media; sound attenuation and ventilation improvements for the high service pump station; installation of a variable frequency drive and soft start motor for pumps at the raw water pump station; installation of new raw water and finished water flow meters, and several improvements to the residuals management facilities. Work is generally complete on the reinforced concrete placement for structure foundations. The GAC building foundation is 95% complete and the chlorine contact tank and equalization basin are complete. Large diameter ductile iron pipe installation between the existing filter building and the new chlorine contact tank and GAC facility is complete, including the connection to the filtered water pipe gallery. Work has been completed on the installation of the new GAC building electrical service line. The new wash water recycle line is about 95% complete, and piping realignment in the sludge pumping station is nearly complete. Rehabilitation of filter No. 3 has been completed and is back in service. Filter No. 2 is being rehabilitated. Observatory WTP Construction of a new chlorine contact tank; upgrades to chemical feed systems, and installation of a finished water flow meter. The foundation excavation for the intermediate pump station, new GAC building, and chlorine contact tank are complete. The

2 reinforced concrete foundations for the GAC building, chlorine contact tank, and intermediate pump station are complete. Various large diameter ductile iron pipes have been installed, as well as the vertical turbine pump chambers for the intermediate pump station. The GAC contactor vessels are 95% complete. Various large diameter ductile iron pipes have been installed, as well as the vertical turbine pump chambers for the intermediate pump station. Various electrical conduit and wiring have been installed at the site. The equipment for the flocculator rehabilitation, including the wiring in the electrical room has been installed. Work has started on upgrades to the existing chemical feed equipment in the filter building. North Rivanna WTP Installation of new filter control valves; new pump control valves; new filter sludge removal equipment; new electrical system upgrades throughout the plant; new finished water flow meter, and the installation of a surge relief mechanism. A new finished water flow meter and filter backwash water piping connection are complete. The intermediate pump station, and the GAC building foundation work is 85% complete. The new finished water pipe connection to the existing clearwell has been completed. The new filter backwash is complete. Crozet WTP Upgrade of the chlorine feed system to a modern hypochlorite feed system, install a finished water meter with appurtenances, and replacement of the existing fluoride and corrosion inhibitor chemical feed systems. The GAC building and intermediate pump station concrete foundation work is 85% complete. Some of the new storm sewer system is installed, as well as new waterline piping. New waterline connections for potable water and backwash water to the GAC building will begin soon. Scottsville WTP The GAC building and intermediate pump station, and the reinforced concrete foundation work is 85% complete. The storm water sand filter excavation is complete. Additional waterline construction for the GAC process will be starting soon. Rivanna Pump Station Work is ongoing on the Rivanna Pump Station on RWSA property and the tunnel work is completed, with pipe installation also complete. Reinforcing steel, conduit installation, and concrete pours for the concrete walls of the new pump station have been completed up to ground level. The 1,600 foot tunnel and installation of a new 60 inch sewer interceptor pipe is complete. Construction of the pump station structure, including the roof, is nearly complete. The project continues to be several months behind, with expected completion in June The new pump station is expected to

3 be in service in the spring, and then the contractor will demolish the existing pump station in Riverview Park. Project is 84% complete. Schenk s Branch Sewer Line This is a 100% City funded project serving only the City, and City customers. This project is part of the DEQ Consent Order requiring completion. The project has been divided into two phases (1) a section between Schenk s Greenway (at Allied Street) to the McIntire Recycling Center and (2) the Recycling Center to the Preston Avenue section (under negotiation between the City and County, which has not been finalized). The Phase 1 construction contract has been awarded and work began in early July Excavation is ongoing on the project along McIntire Road in the Schenk s greenway area. The project construction has been slowed with difficulties in excavating in rock, unsuitable material and contaminated soils with a deep sewer installation, including adverse weather conditions. Construction completion of phase I is expected in March 2017, sewer pipe and manhole installation work will continue over the next several months, to be followed by completion of the Greenway, including extending the walking path and installation of landscaped areas. A change order was approved due to rock removal that was unanticipated. See attached memo for further background information. Project is 85% complete. Reservoir Management Study The project work by Dinatale Water Consulting is well underway, and they are reviewing the background information that has been provided. The primary goal for the study is recommendations for improved reservoir water quality, especially dealing with the algal bloom issues that occur seasonally. The study includes all five reservoirs used for the public water supply: Beaver Creek, Ragged Mountain, South Fork Rivanna, Sugar Hollow and Totier Creek. Additional water quality monitoring will occur during the winter to determine the feasibility of in-reservoir air machines to reduce algae growth. Final report is due November Work is 60% complete. Wholesale Water Metering This was a project required in the Water Supply Agreement to assure accurate water use data for future City and ACSA cost allocations. Additional easements were needed and have been granted. New metering has been installed at three of the urban water plants with the GAC/Water Plant Improvement Projects. The contract for $2.07 million has been approved. Construction is underway and is behind schedule. Construction of the first nine meter sites is complete, and two more are underway, out of 27 locations overall. The contractor has brought in an additional crew to speed up progress, and a third crew is planned to start in February. Project is 40% complete Working Agreement ( Working Agreement on Urban Area Wholesale Flow Allocation and Billing Methodology ) The existing 1983 Working Agreement for water is currently used to establish monthly billings by RWSA to the ACSA and the City for the Urban water bill. The Wholesale Water Metering Project, once complete, will change the approach and consequently the Working

4 Agreement will need to be amended. We are reviewing the agreement and will be having discussions with RWSA and City staff as a next step. The metering project has been delayed and work is slow. Due to the construction delay, it is not anticipated that the meters will be in place for the 2018 Budget. Initial drafting work and discussions have started occurring. VDOT Route 29 Solutions Route 29 Widening and Berkmar Drive Extension The VDOT Route 29 Widening project includes widening of Route 29 (Seminole Trail) from a four-lane divided highway to a six-lane divided highway from Polo Grounds Road to Town Center Drive at Hollymead Town Center. Due to the proposed grade changes and full depth pavement replacement, VDOT has determined that RWSA s existing 12-inch cast iron water line along Route 29 is in conflict and must be relocated for the entire length of the project. RWSA had previously identified through master planning that a 24-inch water main will be needed from the South Rivanna Water Treatment Plant to Hollymead Town Center, in order to meet future water demands. RWSA has requested that VDOT and its Design-Build Contractor relocate the existing 12-inch water main as a 24- inch water main, and according to VDOT policy, VDOT would bear the cost of relocation as a 12-inch line and RWSA would bear the additional cost for the betterment from 12-inch to 24-inch. Construction is underway and 33% complete, with estimated completion by April Moore s Creek AWRRF (Advanced Water Resource Recovery Facility-new name) Odor Control Recommendations for odor control improvements that would significantly control odors from traveling beyond the Moore s Creek AWRRF fence line were presented to the RWSA Board of Directors (BOD) in December, 2014 and a CIP project for $9.33 million was approved at the January, 2015 BOD meeting. The design for odor control improvements includes covering the head works and screening channels, installing grit facilities, constructing a bypass line through on equalization basin, covering the primary clarifiers, building additional odor scrubbing facilities to treat the foul air from the covered sources and the New Rivanna Pump Station, removing the postdigestion clarifiers from service, modifying the handling, hauling and storage of biosolids on-site, cleaning the equalization basins and holding ponds, and coating the interior of the digesters. Construction work on the odor control project is completed with pouring the concrete foundation for the new biological scrubber. Demolition has begun on the concrete bottoms of the existing grit chambers. Additional construction work includes driving helical piles to provide additional structural support for the new second floor of the grit building. Mechanical installation work will proceed once demolition and subsurface activities are complete. The project is anticipated to be completed in January RWSA is also purchasing new covered trailers for sludge storage, which may help in the short-term with odors in the Moores Creek area. Digester sealing bidding to seal the interior and eliminate gas emission. Holding ponds, which are the source of the odors, are being cleaned out. Project is 25% complete.

5 Crozet Pump Station Odor Control Odor control efforts are being made to the Rt. 250 west area of the Crozet wastewater pump stations, where recent citizen complaints have originated. New odor control chemical contract to better manage pump station odors. South Rivanna Hydropower Plant Rehabilitation RWSA constructed a hydropower plant at the South Fork Rivanna Dam in Power generation at the plant was limited for a number of years due to various mechanical issues and has been completely offline for the past two years. The Board approved surrendering the license and decommissioning the facility based on the lack of a return on the capital investment, and impacts on managing the water supply and flow releases to the river. South Fork Reservoir to Ragged Mountain Pipeline The adopted RWSA CIP Budget has $2,295,000 budgeted to the right-of-way and feasibility phase, with funding beginning in July, 2017 (FY 2018). The future construction of a new pipeline is part of the 50-year Community Water Supply Plan to increase the future transfer capacity through replacement of the Sugar Hollow Pipeline along an alternative alignment to be determined. The pipeline project will involve a more detailed routing study to determine the most feasible alignment with work to begin in July, Crozet Water Plant Capacity Study As Crozet continues to grow, RWSA monitors the water treatment plant sizing to meet water demand (use) on the maximum day (24 hour period) of each calendar year. RWSA will be conducting a preliminary engineering evaluation of a future water plant expansion at Crozet, as part of the FY 2017 CIP. Current trending is indicating that the maximum day demand could reach the current capacity (1 MGD) of the Crozet Water Treatment Plant as soon as An engineering firm was approved to conduct this engineering study, and the ACSA is gathering consumption data for the study. Crozet Finished Water Pump Station As part of the current FY 2016 CIP, the Crozet Water Treatment Plant is being studied to expand the treatment capacity to secure future demand needs of the Crozet community. Prior to any plant expansion, it has been determined that the finished water pumping facilities are in dire need of replacement. The Finished Water Pump Station (FWPS) is a new design project to fully replace the antiquated existing pump station, and will be constructed ahead of any plant upgrades. The existing pump station is very small and was constructed as part of the original plant construction in the late 1960s. The pumping equipment and controls are out dated, and operational reliability and efficiency have been drastically impaired. Operational reliability is limited, and the pump house has inadequate heating and cooling. The pump house is located in a low, poorly drained area near the ground storage clearwell, and drainage issues exist. Due to the age and condition of pumps, electrical systems, building systems, and controls, it has been determined that a full station replacement is necessary. The

6 new pump station building will be of similar construction as what is being built for the GAC facility at Crozet WTP. The preliminary engineering report is complete and approved by the Virginia Department of Health. Design plans and specifications are being developed. Meetings with Albemarle County staff have been held in an effort to facilitate the regulatory approvals for the new pump station building. The pump station building design is 100% complete with bidding planned for early Observatory Water Treatment Plant The Observatory Water Plant was built in 1949, with some rehabilitation work done in There are several water treatment plant projects at Observatory scheduled in the Capital Improvements Plan (CIP). The most immediate project is to replace the existing flocculator equipment and repair basin inlet troughs, replace valves, install a new baffle wall and SCADA control equipment. The flocculator work has begun. Further work is phased over the five year CIP. Rivanna Water and Sewer Authority Strategic Plan The Board of Directors has requested that a Strategic Plan be developed for the Rivanna Water and Sewer Authority (RWSA). Project is on hold until the summer. Moore s Creek AWRRF (Advanced Water Resource Recovery Facility Wastewater Treatment) Roof Replacements Major maintenance work to replace aging roofs (35 years plus in age). Project was approved in the CIP (Capital Improvement Program). Crozet Flow Equalization Tank (FET) Rehabilitation work in the RWSA and Albemarle County Service Authority (ACSA) sewer systems is on-going to meet inflow and infiltration (I&I) reduction goals in the Crozet Interceptor sewer basin based on the flow metering and modeling results of the Comprehensive Sanitary Sewer Model and Study conducted in The intent was to reduce I&I in the system to meet the 2020 two-year storm flow targets. Based on the results of that study, it was determined that the Crozet Interceptor system and namely the existing Crozet Pump Stations (1 through 4) have adequate capacity to handle the 2015 peak wet weather flow from the Crozet service area during a two-year storm. However, as projected growth in the service area occurs, peak wet weather flows in the area under the storm conditions established in the updated model will begin to exceed the firm capacities of the pump stations by The construction of a flow equalization tank was identified as the best method to alleviate wet weather capacity issues. RWSA is performing a siting study for the flow equalization tank project which is due to be completed in These services will include the sizing of the flow equalization tank and the pumping station based on information from the updated model, a preliminary site selection process based on the sizing requirements identified, and an alternatives analysis performed for each selected site to evaluate the feasibility of locating the

7 facility. Pump testing is being performed at the four pump stations that are part of the Crozet interceptor system. South Rivanna Water Plant Screen Replacement The 1965 raw water pump station screen (leaf screen) at the South Rivanna Water Treatment Plant is in need of replacement. A contract notice to proceed has been issued. South Rivanna Water Treatment Plant Attached is a presentation on the operation of the plant and the current construction. Moore s Creek Advanced Water Resource Recovery Facility Change order requested and Board approved to add a second centrifuge to create redundancy for sludge management at the plant. See the attached memorandum for additional background information on this item. Attachments RWSAUpdateExecSumm021617

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