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11 - Infrastructure and UtilitiesDEIS 11-1 9/12/2018 Chapter 11: Infrastructure and Utilities 11.1. INTRODUCTION This Chapter assesses the potential impacts of the Proposed Project with issues related to water supply, sanitary wastewater, and usage of electricity and gas for energy serving the Project Site. As such, these analyses address the potential for the Proposed Action to have one or more significant adverse environmental impacts that were identified in the Lead Agency’s Positive Declaration (see Appendix A-5). The Proposed Project is anticipated to generate approximately 55,700 gallons per day (gpd) of water/sanitary demand, approximately 35,787 gpd more than the Future without the Proposed Project (the “No Build” condition). Correspondence received from the operators of both the water and wastewater treatment systems indicate that adequate capacity is available to serve the Proposed Project. New water, sewer, gas, and electric/communications lines would be constructed within the Project Site and would connect to existing lines within Arbor Drive. Sanitary sewage would connect to the existing 10-inch private sewer main on the Project Site, which drains to the southwest. The design of the water and sewer system would be subject to the review and approval of the Village of Rye Brook (the “Village”) Engineering Department, United Water Westchester (Suez), and the Westchester County Department of Health. 11.2. WATER SUPPLY 11.2.1. EXISTING CONDITIONS Suez is a private entity that is the regional water supplier. Suez purchases approximately 60 percent of the Village’s water supply from Aquarion Inc., which utilizes the Putnam Reservoir in Greenwich. The remaining 40 percent of the Village’s water is purchased from Westchester Joint Water Works (WJWW), which sources water from the New York City water supply. The Project Site is served by an existing 4-inch potable water line that is connected to an 8-inch water main in Arbor Drive. The connection is in the front of the office building through the covered parking lot. The existing water usage of the Project Site is minimal as the office building is largely vacant. Fire protection for the Site is provided by a series of fire hydrants located along Arbor Drive. Suez indicated that there is adequate pressure and volume within the existing system to provide fire protection to the existing office building. The Applicant is aware of a concern that during extreme drought conditions, Suez has difficulty providing water to the area. However, after discussion with the Applicant’s engineer, Suez noted that they are aware of this situation and that there is infrastructure in place to secure water from different locations during these conditions. 900 King Street Redevelopment 9/12/2018 11-2 DEIS 11.2.2. FUTURE WITHOUT THE PROPOSED PROJECT In the No Build condition, full occupancy of the existing office building would increase the Site’s water usage. The existing building contains approximately 200,000 square feet (sf) of office space and a cafeteria that was approved to seat 289 persons. Water demand for a fully occupied building was calculated using the measure of approximately 200 sf per employee, which results in approximately 1,000 employees working in the building during a normal work day. Per the New York State Design Standards For Intermediate Sized Wastewater Treatment Systems, NYSDEC, March 4, 2014, each employee would use 15 gallons of water per day and each seat in the cafeteria would use 17 gallons of water per day. Per the New York State Design Standards for Intermediate Sized Wastewater Treatment Systems, each seat in a 24-hour restaurant, a comparable use, would use 50 gallons of water per day. In this case, the 289-seat cafeteria is assumed to only be open 8 hours per day, therefore, 17 gpd was used in the water demand calculations. The combined total water usage for the fully occupied office building would be approximately 19,913 gpd. 11.2.3. POTENTIAL IMPACTS OF THE PROPOSED PROJECT The Proposed Project is estimated to generate a water/sanitary demand of 55,700 gpd (see Table 11-1), approximately 35,787 gpd more the No Build condition. The domestic water usage was calculated based on the various uses proposed in accordance with the New York State Department of Environmental Conservation (NYSDEC) Design Standards for Intermediate Sized Wastewater Treatment Systems, last revised March 5, 2014. Table 11-1 Estimated Water/Sanitary Generation Units Quantity Gallons per Day per Unit Total Gallons per Day Townhouses (Full kitchen) Bedrooms 48 110 5,280 Assisted Living (No in-unit kitchen) Bedrooms 95 110 10,450 Kitchen/Lounge/ Employees 110 Seats/20 Seats/ 64 Employees 50/20/15 6,860 Independent Living (Full kitchen) Bedrooms 301 110 33,110 Total 55,700 Note: Independent Living units are not part of the Assisted Living Facility and for purposes of this analysis are treated as standard apartments. Source: NYS Design Standards for Intermediate Sized Wastewater Treatment Systems, NYSDEC, March 5, 2014. The Proposed Project would install an 8-inch watermain within the Site’s loop road. From that main service, a 4-inch domestic water service and a 6-inch fire service are proposed to serve the main IL and AL building and extensions are proposed to serve the townhouses. The new watermain would connect to the existing municipal main within Arbor Drive at two locations. Fire hydrants would be provided throughout the Site in accordance with the applicable Fire Codes and the requirements of the Rye Brook Fire Department (RBFD). Fire pumps may be required within the proposed buildings. The need for such pumps would be determined based on detailed design and available flows and pressure during the final design of the site’s water systems. In an April 10, 2018 letter, SUEZ confirmed that it has “adequate pressure and volume to serve” the Proposed Project (see Appendix E-3). In a June 5, 2018 letter, SUEZ provided the results of a hydrant flow test indicating the existing flows and pressures Chapter 11: Infrastructure and Utilities DEIS 11-3 9/12/2018 currently available along Arbor Drive (see Appendix E-3). Based upon these results, an analysis of the Proposed Project’s fire flow demand was performed by JMC (see Appendix E-3). This analysis indicated that the available fire flow on-Site would be 1,542 gpm at 20 psi, which is in excess of the estimated Site requirements of 1,000 gpm. Confirmation of this analysis has been requested from SUEZ and will be provided to the Village when it is received. If, based on SUEZ’s model of the water system, storage tanks and pumps would be required to adequately serve the Proposed Project’s fire requirements, they will be included in the Project’s final design. 11.2.4. MITIGATION MEASURES The Proposed Project would construct a new 8-inch watermain within the Project Site to serve the buildings proposed. SUEZ, the Site’s water supplier, has indicated that it has adequate pressure and volume to serve the Proposed Project, therefore, no additional mitigation measures are required. 11.3. SANITARY SEWER 11.3.1. EXISTING CONDITIONS The Site is located within the Blind Brook Sewer District, which is served by the Blind Brook Wastewater Treatment Plant (WWTP). The Blind Brook WWTP has a design capacity of 5.0 million gpd, with a 2014 actual flow of 3.0 million gpd. The Site is served by an existing private 10-inch sanitary main that connects to an existing 8-inch Village-owned main, which proceeds south through The Arbors development, connects to the sewer main running south along Hillandale Road, which connects to the County sewer trunk line at the intersection of Hillandale Road, Loch Land, Beechwood Boulevard, Edgewood Drive, and Woodland Drive. A sanitary sewer flow monitoring analysis was conducted to determine the current flow conditions within the sewer system that serves the Project Site (see Appendix EE). The monitoring indicated that the existing 8-inch sewer flows at approximately 9 percent of its capacity on average and 21 percent of its capacity during periods of peak flow. 11.3.2. FUTURE WITHOUT THE PROPOSED PROJECT In the No Build condition, full occupancy of the existing office building would increase the Site’s sanitary demand. As discussed above, the combined total water/sanitary demand for the fully occupied office building would be approximately 19,913 gpd. 11.3.3. POTENTIAL IMPACTS OF THE PROPOSED PROJECT As described above, the Proposed Project is estimated to generate approximately 55,700 gpd of sanitary sewage, approximately 35,787 gpd more than the No Build condition. As the Blind Brook WWTP has 2 million gallons per day (mgd) excess capacity, the WWTP would be able to serve the Proposed Project. A letter received from the Westchester County Department of Environmental Facilities (WCDEF), confirmed the ability of the Blind Brook WWTP and the Blind Brook Trunk Sewer System to accommodate the increased sewer flows from the Proposed Project (see Appendix E-3). Trash receptacles would be provided by all toilets in the Proposed Project in order to eliminate the potential for non-flushable items to enter the sanitary sewer system. In 900 King Street Redevelopment 9/12/2018 11-4 DEIS addition, grease traps would be provided from proposed common kitchen areas in the IL and AL building to prohibit unwanted greases from entering the sewer system. The grease traps would be maintained on a regular basis to maintain their effectiveness in grease removal. The Proposed Project would construct an 8-inch sanitary service that would connect the IL and AL building to the existing 10-inch private main. Separate connections for each townhouse cluster would be made to the 8-inch main. Based on the Site topography in relation to the existing sewer system, it is not anticipated that a pump station would be required. JMC Engineering conducted a downstream sanitary sewer main analysis to evaluate the theoretical capacity of the sewer system to accommodate the increase in flows from the Proposed Project (see Appendix EE). This analysis calculated the peak flow for each section of the sewer main between the Project Site and the Westchester County sewer main at the intersection of Hillandale Road, Loch Lane, Beechwood Boulevard, Edgewood Drive, and Woodland Drive. The analysis modeled the calculated and actual flows from the Site, The Arbors, and residences along Hillandale Road. Based on this analysis, the existing downstream sanitary sewer system would have sufficient capacity to serve the Proposed Project and accommodate the increased flow. As shown in Table 6 of Appendix EE, the downstream sewer infrastructure has the capacity to handle up to 0.960 cubic feet per second (cfs) of flow, which is well in excess of the 0.645 cfs of flow projected in the post-development condition. In the post- development condition, the existing 8-inch sewer main would flow at 45 percent of its capacity during periods of peak flow. In addition, there are no known capacity issues with the existing 8-inch public main. Therefore, the Proposed Project is not anticipated to have a significant adverse impact to the sanitary system. 11.3.4. MITIGATION MEASURES The WCDEF recommends, as it has done in other County sewer districts, that the additional flow to the system be offset by reductions in inflow and infiltration. The removal for the Proposed Project is recommended to be on a 3:1 ratio. As described above, the Proposed Project is estimated to generate approximately 55,700 gpd of sanitary sewage, which is equal to an increment of 35,787 gpd more than the No Build condition. In accordance with WCDEF recommendations, the Applicant would mitigate the additional 35,787 gpd to the system at a 3:1 ratio, or a reduction in inflow and infiltration in the amount of 107,361 gpd. In coordination with the Village Department of Public Works, the Applicant is currently conducting an investigation to determine the inflow and infiltration into the Blind Brook WWTP through the existing 8-inch pipe network that runs from Arbor Drive, south through The Arbors townhomes community to the intersection of Hillandale Road, Loch Lane, Beechwood Boulevard, Edgewood Drive, and Woodland Drive here it connects to the County trunk line. The purpose of the investigation is to determine the source and quantity of inflow and infiltration, including illegal taps and breaks in the sanitary pipe allowing groundwater infiltration. The investigative methods will include cleaning the mains, video investigation, and smoke testing. Following the investigation, the Applicant would repair the system subject to review and approval by the Village Department of Public Works. If the necessary mitigation would result in less than the required reduced inflow of 107,361 gpd, then the Applicant would Chapter 11: Infrastructure and Utilities DEIS 11-5 9/12/2018 work with the Superintendent of Public Works to provide mitigation at other locations or pay a fee for future repairs by the Village. 11.4. ENERGY USAGE (ELECTRICITY AND GAS) 11.4.1. EXISTING CONDITIONS Electricity and gas service to the Project Site is provided by Con Edison. Electric service is available along Arbor Drive via underground transmission lines. Gas service is also available along Arbor Drive, which is connected to a below-ground medium-pressure gas main. The Project Site currently utilizes a minimal amount of energy as the existing building is largely vacant. 11.4.2. FUTURE WITHOUT THE PROPOSED PROJECT There are no planned changes to the electricity and gas service networks in the vicinity of the Project Site by the build year. In the No Build condition, the full-occupancy of the existing office building would increase the Site’s energy demand. As the existing infrastructure was sized to meet that demand, no adverse impacts would be expected in that condition. 11.4.3. POTENTIAL IMPACTS OF THE PROPOSED PROJECT The Proposed Project would require electricity and gas to power building systems. Con Edison would continue to provide electric service to the site, which would be fed through an underground 13.2 kilovolt (kV) service originating from Arbor Drive. This 13.2 kV service would be tapped by the various buildings on the Project Site with pad-mounted utility transformers at each building. It is anticipated that the existing electric service will accommodate the Proposed Project. A will-serve application has been submitted to Con Edison; however, at the time of publication, a response has not been received. The Proposed Project would be connected to the existing natural gas service along Arbor Drive and a medium-pressure service main would run underground to provide service to all buildings on the Site. Each building would be metered separately. It is anticipated that the existing natural gas service will accommodate the Proposed Project. A will-serve application has been submitted to Con Edison; however, at the time of publication, a response has not been received. 11.4.4. MITIGATION MEASURES The Proposed Project would incorporate energy-efficient features, including fixtures and HVAC and mechanical systems. The use of energy-efficient features would reduce the Site’s energy consumption, which would also reduce the greenhouse gas emissions attributable to the Proposed Project. 