LIMITED ENVIRONMENTAL REVIEW

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2 LIMITED ENVIRONMENTAL REVIEW A. Project Identification Project Name: Lakewood High Rate Treatment (HRT) Facility WPCLF# CS Address: Mark Papke, City Engineer City of Lakewood Detroit Avenue Lakewood, Ohio B. History and Existing Conditions The City of Lakewood, in Cuyahoga County, owns and operates a wastewater collection and treatment system which serves the city. The sewer collection system is comprised of approximately 75 % separate sanitary sewers and 25% combined sewers (pipes that in dry weather carry sanitary sewage only, and during wet weather carry sanitary flows combined with storm drainage). When flows rise dramatically during and after rainfall, combined sewer overflow (CSO) structures divert untreated sanitary sewage mixed with storm water to area streams. Such discharges are threats to human health and the environment. The combined portion of the system contains nine CSOs which discharge to Lake Erie and the Rocky River when the system is overloaded. Six discharge to Lake Erie while the remaining three discharge to the Rocky River. The wastewater treatment plant (WWTP) is an activated sludge-based plant currently designed for an average daily flow of 18 million gallons per day (mgd) dry weather flow and sustained peak primary and secondary treatment capacity for wet weather flows of 30 mgd. The plant discharges to the Rocky River. The proposed project, as required by Lakewood s National Pollutant Discharge Elimination System (NPDES) permit, will provide additional wet weather treatment capacity. One CSO which discharges to Lake Erie will be eliminated. C. Project Description Lakewood proposes to construct a high rate treatment (HRT) system for treatment of flows in excess of the WWTP hydraulic capacity (30 mgd), which occur during wetweather conditions. The chosen technology system is a high-rate physical/chemical process capable of treating peak flows during wet weather periods. The HRT system will be constructed adjacent to the WWTP (see Figure 1).

3 The flow rate to be handled by the HRT system has been estimated using the Storm Water Management Model (SWMM). During wet weather events, flows more than 30 mgd will be diverted to the HRT facility. The HRT system is designed to handle 35 mgd. Thus, this brings the combined wet-weather treatment capacity at the WWTP and the proposed HRT facility capacity to 65 mgd. The proposed process is capable of intermittent operation with short start-up and shutdown times and is designed with two parallel trains which provide maximum operational flexibility of running one or both trains depending on the wastewater flow. The HRT facility consists of the following treatment processes: Headworks - Mechanical bar screens Grit facility - Grit tanks Coagulation mixing tanks Maturation tanks Settling tanks UV disinfection Parshall flume Effluent diversion chamber Related miscellaneous work as may be necessary to complete the contract in accordance with the contract documents. An HRT pilot study showed that the effluent limits outlined in Lakewood s NPDES permit were achieved consistently during the wet weather testing period. The additional capacity provided by the HRT will effectively eliminate one CSO. D. Estimated Project Costs The HRT project will cost approximately $24.4 million. The Ohio Public Works Commission (OPWC) will provide funding for $6.3 million and Lakewood will borrow approximately$18 million from the Water Pollution Control Loan Fund (WPCLF) at the CSO discounted interest rate of 0.29%. During the 30-year loan period, Lakewood will save approximately $11.4 million by using WPCLF dollars at this rate, compared to the market rate of 3.77%. E. Project Schedule The project will take approximately 24 months to complete. The estimated initiation of operation date is September, F. Public Participation

4 Lakewood has held open Clean Water Task Force meetings to discuss the topic and the city s NPDES permit requirements. An attachment was sent out to all residents in the City of Lakewood which discusses the HRT and other CSO projects. Ohio EPA will post this Limited Environmental Review (LER) and Finding of No Significant Impact on the Division of Environmental and Financial Assistance web page: and will provide it to interested parties upon request. G. Conclusion The proposed project meets the project type criteria for a Limited Environmental Review; namely, it is an action within an existing public wastewater treatment system, which is a minor expansion of existing treatment works. Furthermore, the project meets the other qualifying criteria for an LER; specifically, the proposed project: Will have no adverse environmental effect and will require no specific impact mitigation. There will be no significant adverse effects as a result of project implementation, or the need for any additional mitigation measures beyond typical erosion control and construction best management practices. Standard construction best management practices will minimize impacts due to construction noise, dust, and storm water runoff. Is cost effective and not controversial. Annual residential sewer bills are projected to be $336 by This is 0.7% of the median household income (MHI) of $47,145 and is considered affordable. There is no known opposition to the proposed project and it is not overly burdensome to ratepayers; it is therefore not controversial. Does not create a new, or relocate an existing, discharge to surface or ground waters, and will not result in substantial increases in the volume of discharge or loading of pollutants from an existing source or from new facilities to receiving waters, since the project only involves improvements to an existing wastewater treatment facility, not pollutant discharges. Additionally, the project will eliminate a CSO. Does not create a new source of water withdrawals from either surface or ground waters, or significantly increase the amount of water withdrawn from an existing water source, since the project proposes improvements to wastewater treatment equipment that will improve treatment capability, not affect water sources or withdrawal amounts.

5 Will not provide capacity to serve a population substantially greater than the existing population, since the project is not related to serving new growth or increasing capacity at the wastewater treatment facility. The planning activities for the project have identified no potentially significant adverse impacts. The project is expected to have no significant short-term or long-term adverse impacts on the quality of the human environment or on sensitive resources (surface waters, coastal zones, floodplains, wetlands, state-designated scenic or recreational rivers, prime or unique agricultural lands, aquifer recharge zones, archaeologically or historically significant sites, threatened or endangered species, or state and federal wildlife areas). For more information, please contact: Marcus Liston Ohio EPA - DEFA P.O. Box 1049 Columbus, OH (614) marcus.liston@epa.ohio.gov

6 Figure 1. Project Location