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HomeMy WebLinkAbout971968.tiffRESOLUTION RE: ACTION OF BOARD OF COUNTY COMMISSIONERS OF WELD COUNTY, COLORADO, CONCERNING SITE APPLICATION OF TOWN OF BERTHOUD AND AUTHORIZE CHAIR TO SIGN WHEREAS, the Board of County Commissioners of Weld County, Colorado, pursuant to Colorado statute and the Weld County Home Rule Charter, is vested with the authority of administering the affairs of Weld County, Colorado, and WHEREAS, the Board has received a site application from the Town of Berthoud, P.O. Box 1229, Berthoud, Colorado 80513, concerning the capital improvements (digester, lift station and force main/trunk sewer main) to the wastewater treatment plant. located on the following described parcel of land, to -wit: SE%, SW%, Section 19, Township 4 North, Range 68 West of the 6th P.M., Weld County, Colorado WHEREAS, the regulations for site applications for capital improvements (digester, lift station and force main/trunk sewer main) to the wastewater treatment plant require review of the site application by the Board of County Commissioners, and further, that various local and state agencies be given the opportunity to review and comment on said site application, and WHEREAS, the site application from the Town of Berthoud was submitted to the Board of County Commissioners of Weld County for review and comment, a copy of said application being attached hereto and incorporated herein by reference, and WHEREAS, after study and review, the Board finds that said site application is not in conflict with the Weld County Comprehensive Plan, and that it is in the best interest of Weld County to recommend approval of said application. NOW, THEREFORE, BE IT RESOLVED by the Board of County Commissioners of Weld County, Colorado, that the site application submitted by the Town of Berthoud be, and hereby is, recommended favorably to the Colorado Department of Public Health and Environment, thereby indicating the Board finds no conflict with the Weld County Comprehensive Plan. BE IT FURTHER RESOLVED by the Board that the Chair be, and hereby is, authorized to sign said site application. 971968 PL0079 SITE APPLICATION - TOWN OF BERTHOUD PAGE 2 The above and foregoing Resolution was, on motion duly made and seconded, adopted by the following vote on the 10th day of September, A.D., 1997. ATTEST: GAG Weld Cou ty Clerk to the Board BY `mil /.vn Al/t/.// Deputy Clerk to the Board APPRO AST• SRM: ounty Attor y Dale K. Hall BOARD OF COUNTY COMMISSIONERS WELD UNTY, CODO eorge'E. Baxter, Chair tzia ;ess�ance L. Harbert, 1,C2 -Tern, EXCUSED Barbara J. Kirkmeyer W. H. Webster w2 971968 PL0079 a IMISS MSS MININSIESealegemar McLaughlin Water Engineers, Ltd. July 7, 1997 Town of Berthoud Ms. Anna Lenahan, Administrator P.O. Box 1229 Berthoud, CO 80513 2420 Alcott Street, Denver, Colorado 80211 (303) 458-5550 Facsimile (303) 480-9766 mwe@ecentral.com RE: Site Application - New VVWTP (Digester and Lift Station) Dear Ms. Lenahan: RONALDC MCLAUGHLIN LEO Rf. EISEL HALFORD E ERICK-FON WILLIAM R KENDALL RALPH L TOREN TERRENCEP. KENYON RICHARD MMUGHLIN RONALD MCLAUGHLIN GERALD L LAMB GENE A BURRELL MICHAEL E MERCER JOHN M. PFLAUM MICHAEL R GALGZZI SCOTT E. LEHMAN BRIANS KOLSIAD O. DEAN DEROSIER EDWARD D BAIN BRIANE CHEV ALTER DANIEL F. BLAHA LEANDER L L'RMY DANIEL M PETRAM ALA RONALD D LUCERO Submitted attached is the complete Application for Site Approval for capital improvements (digester, lift station, and trunk sewer/force main) to the new Wastewater Treatment Plant Site. The engineering basis for the Application is furnished in two Preliminary Engineering Reports. The basic report, dated July 1997, submitted herewith, is tailored to provide the ancillary information required to support the site application. Other preliminary engineering was completed earlier, and was presented earlier in our May, 1996, Wastewater Master Plan Update, which (to avoid duplication) is attached as Appendix A. The site application, with supporting reports, should be submitted initially to: • The Berthoud Board of Trustees • Weld County: Planning Commission; Health Department; Commissioners • North Front Range Water Quality Planning Association • Colorado State Geologist After review by the above agencies, the site application should be forwarded to the Colorado Water Quality Control Division. We will be available for discussion and/or to provide additional information to any of the above review agencies. Ve y uls�� Christo er K. Gulden Enclosures d/C91,14-4-• Ronald C. McLaughlin P:\1992\92-008\00600\wp j wAL7-7.WPD 971963 .NTRO 'MPLETE ENGINEERING SERVICES IN WATER RIGHTS AND RESOURCES WATER TREATMENT AND DISTRIBUTION SUBSURFACE DRAINAGE IRRIGATION HYDROGEOLOGY STORM DRAINAGE AND FLOOD CONTROL WASTEWATER COLLECTION TREATMENT AND REUSE FIRE PROTECTION WATER BASED RECREATION SPECIALTY HYDRAULICS RATE STUDIES AND UTILITIES ECONOMICS COLORADO DEPARTMENT OF HEALTH Water Quality Control Division Building B, Suite BP30 "-'00 Cherry Creek Drive South _aver, Colorado 80222-1530 APPLICANT: Town ADDRESS: P.O. Box 1229 Berthoud, Colorado 80513: 328 Massachusetts Ave. PHONE: Consulting Engineer's Name and Address: McLaughlin Water Engineers. Ltd. APPLICATION FOR SITE APPROVALFOR CONSTRUCTION OREXPANSION OF: A) DOMESTIC WASTEWATER TREATMENT WORKS (INCLUDING TREATMENT PLANTS, SEWERS, AND LIFT STATIONS) OVER 2,000 GPD CAPACITY. '^ B) INTERCEPTORS (IF REQUIRED BY C.R.S. 25-8-703 (3)) any A 1tj01P `4of Berthoud��I/`ar` N ' (970) 532-2643 2420 Alcott Street, Denver. CO 80211 PHONE: (303) 458-5550 Summary of information regarding new sewage treatment nlytl: 1. Proposed Location: (Legal Description) SE Township 4 N , Range 68 W. 1, SW 'k Section fl Weld County. 2. Type and capacity of treatment facility proposed: Processes Used Aerobic Sludge Digester Sludge Thickening. Return Flow/Sewage Lift Pump Station. Trunk Sewer. Force Main Hydraulic 900 000 Organic 1 300 gal/day lbs. BOD5/day Present PE 6.300 Design PE 7.000+ % Domestic 99+ % Industrial 1- 3. Location of facility: Attach a map of the area which includes the following: (a) 5 -mile radius: all sewage treatment plants, lift stations, and domestic water supply intakes. (b) 1 -mile radius: habitable buildings, location of potable water wells, and an approximate indication of the topography. 4. Effluent disposal: Surface discharge to watercourse Little Thompson River Subsurface disposal N/A Land N/A Evaporation N/A Other N/A State water quality classification of receiving watercourse(s) Proposed Effluent Limitations developed in conjunction with Planning and Standards Section, WQCD: BODS N/A mg/I SS N/A mg/I Fecal Coliform N/A /100 ml Total Residual Chlorine N/A mg/I Ammonia N/A Other 5. Will a State or Federal grant be sought to finance any portion of this project? Unknown 6. Present zoning of site area? None Zoning with a 1 -mile radius of site? Mixed 7. What is the distance downstream from the discharge to the nearest domestic water supply intake? There are none. (Name of Supply) 92-008.006 (Address of Supply) -1- WQCD-3 (Revised 8-83) 371968 What is the distance downstream from the discharge to the nearest other point of diversion: No Change (Name of User) (Address of User) 8. Who has the responsibility for operating the proposed facility? The Town of Berthoud 9. Who owns the land upon which the facility will be constructed? The Town of Berthoud (Please attach copies of the document creating authority in the applicant to construct the proposed facility at this site). 10. Estimated Project cost: 52.000.000 Who is financially responsible for the construction and operation of the facility? The Applicant 11. Name and addresses of all water and/or sanitation districts within 5 miles downstream of proposed wastewater treatment facility site. None (Attach a separate sheet of paper if necessary.) 12. Is the facility in a 100 year flood plain or other natural hazard area? Some of the .Site is. If so, what precautions are being taken? Facilities ar€.1.9 be constructed on portions Qfjhe sije that are out of the 100 -year flood .plain. Has the flood plain been designated by the Colorado Water Conservation Board, Department of Natural Resources or other Agency? No. (See attached flood plain report) (Agency Name) If so, what is that designation? 13. Please include all additional factors that might help the Water Quality Control Division make an informed decision on your application for site approval. The proposed facilities provides sludge processing and is the first phase in a program to strattgically relocate the regional plant processes at a new site which will permit economical gravity service to the majority of the service area. B. Information regarding lift stations: 1. The proposed lift station when fully developed will generate the following additional load: Peak Hydraulic (MGD) 0.15 P.E. to be served 400 (Lift Station is temporary) 2. Is the site located in a 100 year flood plain? No If yes, on a separate sheet of paper describe the protective measures to be taken. 3. Describe emergency system in case of station and/or power failure. Generator with on -site source of fuel. 4. Name and address of facility providing treatment: Town of Berthoud Wastewater Treatment Plant 5. The proposed lift station when fully developed will increase the loading of the treatment plant to 80 % of hydraulic and 80 % of organic capacity and Applicant agrees to treat this wastewater? Yes X No Date Signature and Title 92-00A.CO6 -2- WQCD-3 (Revised 8-83) 971968 C. If the facility will be located on or adjacent to a site that is owned or managed by a Federal or State agency, send the agency a copy of this application. D. Recommendation of governmental authorities: Please address the following issues in your recommendation decision. Are the proposed facilities consistent with the comprehensive plan and any other plans for the area, including 201 Facility Plan or 208 Water Quality Management Plan, as they affect water quality? If you have any further comments or questions, please call 320-8333, Extension 5272. 1. 2. Recommend Recommend No DateApproval Disapproval Comment 3. 11/P/9% t/ 4. 5775f(-± 5. 7. Sigttptuye pf RwreL native Management Agency Local Government: Cities or Towns (If site is inside boundary or within three miles) and Sani- tationpistricts. Board of C untyCommissioners lb/ z` al Health Authority City/county Planning Authority Council of Governments/Regional Planning State Geologist ;For lift stations, the signature of the State Geologist is not required. Applications for treatment plants require all signatures.) certify that I am familiar with the requirements of the "Regulations for Site Applications for Domestic Wastewater Treatment Works," and lave posted the site in accordanre with the regulations. An engineering report, as described by the regulations, has been prepared and is Inclosed. 92-008.906 -3- WQCD-3 (Revised 8-83) 971968 ATTACHMENT TO SITE APPI ICATION accordance with C.R.S. 1981, 25-8-702 (2)(a), (b), and (c), and the "Regulations for Site Applications for Domestic Wastewater Treatment Works," the Water Quality Control Division must determine that each site location is consistent with the long-range, comprehensive planning for the area in which it is to be located, that the plant on the proposed she will be managed to minimize the potential adverse impacts on water quality, and must encourage the consolidation of wastewater treatment works whenever feasible. In making this determination, the Division requires each applicant for a site approval for a domestic wastewater treatment works to supply an engineering report describing the project and showing the applicant's capabilities to manage and operate the facility over the life of the project to determine the potential adverse impacts on water quality. The report shall be considered the culmination of the planning process and as a minimum shall address the following: Service area definition including existing population and population projections, flow/loading projections, and relationship to other water and wastewater treatment plants in the area. Proposed effluent limitations as developed in coordination with the Planning and Standards Section of the Division. (Allow minimum four weeks processing time.) Analysis of existing facilities including performance of those facilities. Analysis of treatment alternatives considered. Flood plain and natural hazard analysis. Detailed description of selected alternatives including legal description of the site, treatment system description, design capacities, and operational staffing needs. Legal arrangements showing control of site for the project life. Institutional arrangements such as contract and/or covenant terms for all users which will be finalized to accomplish acceptable waste treatment. Management capabilities for controlling the wastewater throughout and treatment within the capacity limitations of the proposed treatment works, i.e., user contracts, operating agreements, pretreatment requirements. Financial system which has been developed to provide for necessary capital and continued operation, maintenance, and replacement through the life of the project. This would include, for example, anticipated fee structure. '. Implementation plan and schedule including estimated construction time and estimated start-up date. Depending on the proposed project, some of the above items may not be applicable to address. In such cases, simply indicate on the application form the non applicability of those. 9z-005.006 -4- WQCD-3 (Revised 8-83) 971969 ENGINEERING REPORT WASTEWATER TREATMENT PLANT IMPROVEMENTS AND APPLICATION FOR SITE APPROVAL for the TOWN OF BERTHOUD McLaughlin Water Engineers, Ltd. July 1997 971968 ENGINEERING REPORT WASTEWATER TREATMENT PLANT IMPROVEMENTS for the TOWN OF BERTHOUD TABLE OF CONTENTS SECTION I - INTRODUCTION BACKGROUND 1 PURPOSE 2 SECTION II - EXISTING WASTEWATER TREATMENT PLANT PAST CONSTRUCTION PROGRAMS 3 PROCESS ANALYSIS 3 TABLE HI -A 4 EXISTING PLANT COMPONENTS AND PROCESS LOADING - EXISTING DESIGN OVERALL PLANT PERFORMANCE AND CONCLUSIONS 5 OTHER WASTEWATER TREATMENT PLANTS 5 POTABLE WATER FACILITIES 5 SECTION III - DESIGN BASIS POPULATION AND PLANT LOADING PROJECTIONS 6 SLUDGE HANDLING FACILITIES 7 LIFT STATION/RETURN FLOW PUMP STATION 8 TRUNK SEWER AND SLUDGE CONVEYANCE PIPELINE 8 SECTION IV - LITTLE THOMPSON RIVER AND PLANT EFFLUENT QUALITY STREAM QUALITY 9 PLANT EFFLUENT QUALITY/DISCHARGE REQUIREMENTS 9 SECTION V - MASTER PLAN MODIFICATIONS SERVICE AREA 10 PLANT SITE 10 TRUNK SEWER AND RETURN FLOW FORCE MAIN 11 SECTION VI - INITIAL CAPITAL IMPROVEMENT PROGRAM 12 92-008.006 971968 TABLE OF CONTENTS (Continued) SECTION VI - NATURAL HAZARD ANALYSIS FLOOD PLAIN 13 OTHER HAZARDS 13 SECTION VIII - MANAGEMENT IMPLEMENTATION PLAN 14 LEGAL ARRANGEMENTS 14 INSTITUTIONAL ARRANGEMENTS 14 MANAGEMENT CAPABILITIES 14 FINANCIAL SYSTEM 14 APPENDICES APPENDIX A - WASTEWATER TREATMENT MASTER PLAN UPDATE APPENDIX B - POTABLE WATER WELLS APPENDIX C - BERTHOUD WWTP COMPREHENSIVE PERFORMANCE EVALUATION APPENDIX D - FLOOD PLAIN ANALYSIS REPORT 92-008.006 971968 SECTION I - INTRODUCTION BACKGROUND The Town of Berthoud manages and operates the Berthoud Wastewater Treatment Plant and the gravity collection system, which extends throughout the Town and further north covering the Campion area. The Town has maintained responsibility for the system since its origins in the early 1900s. Responsibility for the northern portion of the collection system was added due to the disbanding of the South Loveland Sanitation District. The treatment plant provides secondary treatment for all sewage collected; to the effluent discharges into No Name Creek. The plant is expected to be at 95% of present design capacity before the year 2010 and is currently overloaded with regard to waste sludge processing capacity. Therefore, preliminary design of new sludge processing facilities is concurrently initiated with the site application, and planning for an expansion is needed to stay within the terms of the discharge permit. The Wastewater Service Area Plan for the Town of Berthoud (Engineering Professionals Inc., December 1985) identified an ultimate service area for Berthoud. This area covered approximately 35 square miles with an estimated a build -out population of 70,000. The Plan identified a new regional plant site with an ultimate capacity of 9 MGD. The Plan recognized the regional treatment value that would occur by moving the plant site further down gradient in the service area, maximizing gravity collection potential and providing long term water quality planning. An update to the 1985 Plan was prepared in 1996 (McLaughlin Water Engineers, Ltd., May 1996). Conclusions of the Update identified the immediate need for waste sludge processing capacity and provided an initial capital improvement program. The program also identified candidate locations for a new regional plant site. Initial treatment infrastructure at the new site was determined to comprise of an aerobic digester and return flow pump station, with site layout considerations for the ultimate location of the regional treatment facility. It was noted that existing WWTP treatment capacity would be beyond design limits in the near -future, and a second phase to the program would include building new secondary treatment facilities at the new site, when development and growth warrant such action. Recent development around Berthoud has occurred in areas not serviceable through gravity collection. Further, urban growth planning has revised the sanitary service area to include regions 92-008.006 971968 that are outside of the gravity collection envelope relative to the existing treatment plant location. Therefore, to minimize the number of several sewage lift stations, the new treatment plant site has been predesigned to collect raw sewage flows and serve as an interim regional lift station. Pumped flows are to be treated at the existing WWTP until second phase improvements are made at the new regional WWTP site. Based on the two studies, Berthoud has acquired property to serve as the new WWTP site. The site is well situated near the Little Thompson River, located 1'/z miles east of the existing plant. Flood plain analysis and soils investigation concluded that the site is not at risk from natural hazards. PURPOSE The purpose of the report is to present an analysis of the existing plant and service demands from the Town. Also, the report provides the basis for design of the needed improvements to the system that include a phased relocation of treatment facilities to a new regional plant site and the addition of a lift station for residentially developing areas, and waste sludge digester. The report is intended to accompany an Application for Site Approval to be submitted to the Colorado Department of Public Health and Environment. 2 92-008.006. 971.968 SECTION II - EXISTING WASTEWATER TREATMENT PLANT PAST CONSTRUCTION PROGRAMS The majority of the existing units now in service were constructed in 1972. Following is a chronologic summary of the development of the plant within the past three decades. The principle plant units were constructed in 1972 (Nelson -Haley -Patterson & Quirk, dated December 1971). The facility replaced a small, old primary treatment plant with an extended aeration secondary sewage treatment process. New units include a grit chamber, oxidation ditch, clarifier, chlorine contact chamber, sludge beds and control building. Plant capacity is rated at 0.901 MGD. An aerobic digester was added in 1980 (McCarty -Hurst & Associates, dated June 1980). The contract provided a single tank aerobic digester and two small sludge drying beds. A boat clarifier was added to the oxidation ditch in 1990 to add capacity for peaking hydraulic loads. The existing plant has functioned well (in terms of meeting permitted effluent criteria), with the exception of the digester, which is hydraulically and organically overloaded. The digester cannot produce a stabilized sludge meeting the new 503 regulations. The result is costly in that large volumes of low solids waste sludge must be hauled off for both treatment and disposal. PROCESS ANALYSIS The plant is of a secondary plant with disinfection. The secondary plant is extended aeration activated sludge. Disinfection can be accomplished by chlorination just before discharge to the chlorine contact chamber. Design loadings for the existing processes are given in Table II -A which provides design criteria. 3 92-008.006 971968 TABLE II -A EXISTING PLANT COMPONENTS AND PROCESS LOADINGS - EXISTING DESIGN Process/Component/Loading N° Design Criteria Preliminary Treatment 1.8 MGD nominal Flow split box/grit chamber 1 ea 4 MGD 2 desired Parshall Flume: 12" x 36" 1 ea 7.4 MGD @ 24" ±10 accuracy Screen: 114" opening motor operated/1- 1 /4"opening manual by-pass screen 3/4" 1 ea 1" to 1 - Secondary Treatment Oxidation ditch: Volume = 1 ea 0.84 MG 2 desired Detention time @ 0.9 MGD 22.4 hr 20-30 hr Organic loading @ 1300 ppd B0D 11.6 #/1000cf <40 Secondary clarifier: 55" diameter, volume = 1 ea 0.124 MG >1 Surface overflow rate @ 0.9 MGD 379 gpd/sf <600 Max. hydraulic loading based on surface 3.32 MGD overflow rate Detention time @ 0.9 MGD 3.3 hr 1-4 Side water depth 7 ft >10 Disinfection C12 contact chamber; volume 20,000 gal Length/width ratio 64 >40 Detention time @ 0.9 MGD 32 min >30 Sludge Handling Sludge drying beds 2 ea 3200 sf Aerobic digestion detention time using a WAS 1 ea 7 days flow rate of 1830 gpd: volume = 65,000 gal Max water depth 17.75 ft Volume available for decanting 47,132 gal 4 92-008.006 971968 Process/Component/Loading Ns Design Criteria Total volume 65,000 gal Sludge Removal Hauling contract with Liquid Waste Management OVERALL PLANT PERFORMANCE AND CONCLUSIONS A comprehensive Performance Evaluation was conducted for the wastewater treatment plant in May 1996. The evaluation was conducted by an EPA 104(g)(1) Outreach trainer from the Environmental Science Department, Red Rocks Community College. A copy of the evaluation is attached (Appendix C). OTHER WASTEWATER TREATMENT PLANTS There are three other wastewater treatment facilities in the service area; Riverglenn, Western MiniNaquero, and Berthoud Estates. All of these facilities are of the small aerated lagoon type, and are managed/maintained through home ownership associations. None of the facilities are close enough to the new WWTP site, from an economic and topographical stand point, for consideration to be connected to the new system at this time. However, they are located within the designated service area of the new plant, and it is anticipated that, in the future, these plants will be abandoned, with service consolidated at the proposed regional facility. POTABLE WATER FACILITIES There will be no discharge from the new site during the first phase of the program. Ultimately, effluent from the new WWTP will discharge into the Little Thompson River, as it currently does from the existing plant 1% miles upstream. There are no diversions downstream for drinking water purposes on the Little Thompson River downstream of the new site's future outfall location. 5 92.008.006 971969 SECTION III - DESIGN BASIS POPULATION AND PLANT LOADING PROJECTIONS Population projections given in the "208" plan by NFRWQPA have been updated (1997)and are presented in Table III -A. Employment and number of day visitors were not provided in the plan. The existing system currently has 2283 taps. About 93% of the taps are residential, and the remainder are businesses/commercial and limited industrial sources. Table III -A Existing Service Area Population 119971 2000 2005 2010 5,740 6,181 6,990 Year at Existing 80% 90% Capacities pesign Capacity Load Design Design Flow (MGD) .904 .73 1997 2005 Organic (lbs./day BOD5) 1300 900 1997 2005 Table III -A also includes total load projections of the Town growth and the addition of flows from the lift station. Design loads from the area served by the lift station are 150 taps initially, and 400 taps at 2005. Sanitary flows from the services are, respectively, 37,500 gpd and 100,000 gpd. It shows that flows to the plant are expected to be at the 95% design level before 2005. Noteworthy to the above projections - is the amount of infiltration/inflow (I/I) in Berthoud's collection system. Analysis in the 1996 Master Plan Update approximated a fixed allowance for I/I of about 400,000 gpd as a reasonable practical assumption. Berthoud has, and continues to repair/maintain the aged collection system. However, the remaining available capacity, as displayed above, will be valid only if continued I/I reduction is sought through corrective work. Organic loading to the plant has been averaged at 0.56 # BOD5/day/tap. Influent sampling methods at the plant are not composited on a flow proportioned basis, yet due to the slightly low percentage of commercial taps in the system, the average appears reasonable, and is recommended for design purposes. 6 92-008.006 971968 SLUDGE HANDLING FACILITIES The existing aerobic digester is grossly undersized. Since it is planned to construct the regional plant at the new site, it would be unwise to invest in permanent type facilities at the existing plant. It is, therefore, proposed to construct the new sludge handling facilities at the future regional plant site. New facilities at the regional plant site are described following. Aerobic sludge digestion with one tank, covered and insulated, having a 50 -foot inside diameter and 20 -foot side water depth; providing about 300,000 gallons. Anticipated sludge quantities (peak month design basis): Biological sludge (WAS) - 1340 pounds solids per day; 1072 pounds per day volatile. Digested sludge solids of 1018 pounds per day: based on 40% VSS reduction. Dissolved oxygen requirement of 36 pounds per hour based on 2 pounds oxygen per pound of VSS destroyed. Aeration to be supplied to digester by fine bubble flexible membrane diffusers. Clean water transfer efficiency of 35%. • Field transfer efficiency of 15% based on alpha of 0.60, sludge temperature of 20°C, and 0.5 mg/I minimum residual. Actual air requirements of 1278 SCFM at 4925' site elevation and 100°F max inlet air temperature. • Ancillary mixing and scum/foam re -entrainment provided by 5 Hp mixer with draft tube. • Aerated waste sludge receiving basin providing about 15,000 gallons capacity to feed the centrifuge in a thickening mode • A grinder pump to deliver WAS (Waste Activated Sludge) (or WDS (Waste Digested Sludge)) to the centrifuge: approximately 70 -100 gpm. 7 92-008O06 971969 • A sludge centrifuge designed for either thickening or dewatering use. Thickened sludge to be approximately 4.5% solids LIFT STATION/RETURN FLOW PUMP STATION • Wet well having about 10,000 gallons operating volume, equipped with two 150 gpm sewage lift pumps. • Aerated grit chamber and bar screen. • 4" HDPE or PVC force main to existing WWfP. TRUNK SEWER AND SLUDGE CONVEYANCE PIPELINE • 24" PVC sewer - Note that this sewer will initially carry the dilute WAS to County Line Road, where a separate 6" HDPE sludge line will carry waste to the digester - and the 24" used to carry sewage to the lift station. 8 92-008.006 971968 SECTION IV - LITTLE THOMPSON RIVER AND PLANT EFFLUENT QUALITY STREAM QUALITY The existing effluent, and future effluent from the new WWTP site, discharges into the Little Thompson River. This reach of stream progresses through primarily farmland for approximately 11 miles through the Town of Johnstown, before connecting with the Big Thompson River. PLANT EFFLUENT QUALITY/DISCHARGE REQUIREMENTS A copy of Berthoud's Discharge Permit is attached to this report, including the latest discharge application. There should be no revisions as a result of the site application since the discharge point is to be the same, as well as permitted capacity. 9 92-008.006 97196g SECTION V - MASTER PLAN MODIFICATIONS SERVICE AREA The Town of Berthoud service area is within the planning area of the North Front Range Water Quality Planning Association (NFRWQPA). Existing service area boundaries are those defined in the Wastewater Service Area Plan (Engineering Professionals Inc., December 1985), covering an area of approximately 35 square miles. The 1985 Area Plan presents analyses of Berthoud ultimate growth area land use and unincorporated Larimer County proposed service area land use summaries. Projected wastewater flows were determined from this analysis. Since the 1985 Area Plan, Berthoud has experienced growth both inside and outside of the Town growth area. Furthermore, Berthoud has annexed property to the east of the service area along Highway 56, out to the intersection of Interstate 25 and Hwy. 56 (approx. 4 miles). Currently, Berthoud is engaged in annexation procedures for a two square mile area surrounding the intersection. It is anticipated that primarily commercial development and minor residential development will occur there. As a result of residential development near Berthoud, but just outside of the existing service area, and from the 1-25 annexation area, the service area has recently been enlarged and is currently in the amendment process with NFRWQPA. A map (Dwg. V -A) of proposed service area additions is included with this report. PLANT SITE The existing WWTP site is not strategically located to receive a majority of flow from the service area by gravity. The available site area is limited, and does not provide sufficient area for expansion. Further, the present plant facility was not planned for expansion - and the process used is not conducive to enlargement. As presented addressed in the 1985 Area Plan, a new sub -regional plant, better located with respect to the natural drainage collection of the service area, should be acquired. The Area Plan indicated a proposed plant location on the north bank of the Little Thompson River, just east of the Larimer County boundary. MWE field investigation indicated that this specific location did not provide adequate usable area. The 1996 Master Plan Update identified four candidate site locations, all of which were in the 10 971968 92008.006 proximity of the site indicated in the 1985 Area Plan, near the Little Thompson River. Flood plain analysis was conducted, and concluded that three of the sites were at risk. After negotiations with land owner, Berthoud acquired a 10 acre site located 1% miles form the existing site and is'/ mile east of the Larimer)Weld County line (SE %, SW''/ Section 19, Weld Co.). The site was not one of the candidate sites identified in the 1996 Update, yet it is well situated on the south side of the Little Thompson River, and is strategically located to serve a large natural drainage collection area. The majority of the site is above the 100 -year flood plain level. The land use surrounding the site is predominately farmland. There are 4 scattered single family dwellings and barns near the site, the closest being approximately 1,100 feet, all other being a minimum of 2,500 feet away. Access to the site is uninhibited, with and existing unimproved roadway approaching from the west, and feasiblely, access could be provided from the south. TRUNK SEWER AND RETURN FLOW FORCE MAIN Preliminary design of the initial phase of the system includes a trunk sewer and return flow force main to be routed from the existing plant to the new plant site. A gravity sludge conveyance pipeline is also required along part of the alignment. Installation of the trunk sewer is to ultimately serve the existing collection system to the new site, the lower reach will initially collect sanitary flows from newly developed area to the east of Berthoud. The alignment of the pipelines are also shown on drawing V -A. The layout requires approximately 10,000 l.f. of 24" trunk sewer, 3,120 l.f. of 6" sludge conveyance (both gravity flow) and 8750 l.f. of 4" force main. Probable connections to the trunk sewer, from new east Berthoud development will occur along 6C Road, and on County Line Road. Berthoud has obtained a thirty foot wide easement extending from the west side of the new site towards the existing site access road, which is to serve as a utility corridor. 11 92-008.006 9'71.969 SECTION VI - INITIAL CAPITAL IMPROVEMENT PROGRAM New WWTP site master planning is shown on Drawing VI -A. Initial phase capital improvements are shown therein. The following figures present estimated construction costs (1997 dollars) for the proposed improvement program. Item Sludge treatment facilities 0.3 MG Digester, Centrifuge, pumps, Wet well, Oper. Bldg. (at new plant site) 24" trunk sewer (1.9 mi.) 4" HDPE force main(1.62 mi.) 6" HDPE sludge line (0.59 mi.) Improvements at existing STP Total construction cost estimate estimated Cost (1997) $950,000 $1,100,000 $50,000 $2,100,000 The minor improvements planned for the existing WWTP are to maximize its useful life and to accommodate process modifications created from the addition of the improvements listed above. 12 971.968 92-009.006 SECTION VI - NATURAL HAZARD ANALYSIS FLOOD PLAIN A copy of the Flood plain Analysis Report (McLaughlin Water Engineers, Ltd., February 1997) is attached to the report. Summarizing the Report; the hydraulic analysis shows that the 100 -year flow [Little Thompson River] is largely confined to the immediate channel area. All bridges have adequate capacity for the 100 -year flow except the 6C Road bridge, where some road overtopping would occur. The resultant shallow overflow north of 6C Road would re-enter the channel upstream of the County Line Road bridge, as shown on the drawing. The analysis shows that the proposed wastewater treatment plant site is largely unaffected by the 100 -year Flood plain. OTHER HAZARDS There are no other known natural hazzards. 13 92-008.006 971968 SECTION VIII - MANAGEMENT IMPLEMENTATION PLAN It is Berthoud's intent to have new facilities available and in service as rapidly as the program will allow. As was discussed in the evaluation of the existing plant, there is an immediate need for sludge processing capacity. Additionally, service from the lift station is expected to be operational as shown on the attached project schedule. This will allow Berthoud to meet its goals of providing timely service. LEGAL ARRANGEMENTS The new VWVTP site is owned by the Town of Berthoud. Required easements for the trunk sewer alignment are being pursued. INSTITUTIONAL ARRANGEMENTS The Town of Berthoud is responsible for providing design and construction of facilities that will meet the requirements of the Colorado Department of Public Health and Environment. MANAGEMENT CAPABILITIES The Town of Berthoud manages and is responsible for the operation and maintenance of all treatment facilities and collection system components. A copy of Ordinance N° 708 regarding wastewater line extensions is attached. FINANCIAL SYSTEM A copy of Berthoud's proposed project financing is attached. 14 971968 92-008.006 05/22/1997 08:06 19705323534 BERTHOUD PD PAGE 02 MEMORANDIM May 20, 1997 To: Mayor Richard Strachan Board of Trustees Prom: Anna M. Lenahan, Administrator Re: Water/Wastewater/Drainage Projects Please review the following estimated cost proposed financing for the water/wastewater/drainage projects: Water Raw water line from Carter Lake Reservoir bypass line Water Treatment Plant Expansion Add filters 3 & 4 Drainage project Drainage to Bacon Total cost Wastewater Sludge treatment facility 24" trunk sewer/4" DIP force 1-25 lift station/force main Improvement to WWTP Total Cost $1,009,000 186,000 1,800,000 325,000 591,449 600,000 $4,511,449 $850,000 main 780,000 1,500,000 50.000 $3,180,000 Cash $1,000,000 Bonding $1,009,000 186,000 800,000 325,000 400,000 191,449 600,000 $1,400,000 $3,320,000 Cash Bonding 600,000 250,000 780,000 1,500,000 50,000 $600,000 $2,580,000 971.96.q ORDINANCE NO. 708 AN ORDINANCE MODIFYING TITLE 21 OF THE MUNICIPAL CODE OF THE TOWN OF BERTHOUD, LARIMER COUNTY, COLORADO, CONCERNING THE WATER AND WASTEWATER LINE EXTENSION POLICY, AMENDING TITLE 21. BE IT ORDAINED BY THE BOARD OF TRUSTEES OF THE TOWN OF BERTHOUD, LARIMER COUNTY, COLORADO: 21-1-101. Introduction. (1) Statement of Purpose. It is the purpose of this policy to provide a fair and equitable distribution of the costs of installing water and wastewater lines to all the parties benefiting from their installation. This policy covers most cases, but a recognition is made that special cases may occur. When special cases do occur, deviations may be made from the specifics of the policy, provided the final arrangements maintain this fair and equitable intent. Such arrangements can be made through the mutual consent of the Town Administrator and the developer of the property. Such arrangements shall be contained in a development agreement executed by the developer and the Town. This ordinance shall be interpreted and enforced to ensure that a development will pay all direct costs and their proportionate share of indirect costs. (2) Definitions. (a) "Town" means the Town of Berthoud, Colorado. (b) "Development" means the creation of two or more parcels of land. (c) "Developer" means the subdivision developer, parcel owner or any other party or parties within the Town's urban service area. (d) "Property" means the subdivision, parcel, lot, tract or any other described piece of land for which the water or wastewater line is being installed. (e) "Utility Superintendent" means the Superintendent of the Town of Berthoud Water or Wastewater Department. (3) Line Installation Policy. In order to facilitate the orderly continuation of the Town's water distribution and wastewater collection systems, water and wastewater mains shall be installed to the furthest point or points of a property. The developer shall install lines on more than one side of the property and/or through more than one internal easement or right-of-way if it is determined that those lines are needed to provide service to other properties beyond the subject property. 1 971968 (4) All mains which are necessary for the service to or within a property or as required above, shall be installed at the cost of the developer, except for the following conditions: (a) Mains larger than those required to serve the property but required by the Town shall be subject to the provisions of 21-1-102, below. (5) Prior to construction, plans and specifications for the water and wastewater systems to be installed shall be reviewed and approved by the Town Administrator after consultation with the appropriate engineering and other appropriate staff, (6) The developer shall be responsible for payment of the Town's review, inspection and associated costs. Such costs shall be in accordance with the actual costs. Payment of such costs shall be made prior to acceptance by the Town of the improvements by the Town. (7) Upon completion of the work and written acceptance by the Town the water distribution and wastewater collection systems shall become the property of the Town. (a) The Town shall own and maintain the water mains, water main appurtenances, and fire hydrants and appurtenances therein. The property owner shall maintain the service line attachment to the main line, meter, meter pit, vaults and all other appurtenances from the main line. For fire service lines the Town's ownership ends at the valve on the main or the point of connection to the last domestic service off the line. (b) The Town shall own and maintain the wastewater mains, manholes and regional wastewater lift stations. The property owner shall maintain the wastewater service line and attachment to the main line. Where a lift station is built to provide service to a specific development or area the Town may either establish a special monthly assessment to cover maintenance, overhead and depreciation or require a property owner's association to cover these costs. (8) All workmanship and materials shall be warranted in writing by the developer against any defects for a period of one year from the date of acceptance by the Town. Any repair or reconstruction performed during such warranty period as a result of defects in material and/or workmanship shall be warranted for a period of one year from the acceptance of such repair or reconstruction by the Town. (9) Properties which are served by private lines that were not constructed according to Town approved plans and specifications shall have mains complying to Town standards installed and extended to serve the property. The cost thereof shall be paid by the owners served, or assessed against the owners in accordance with applicable laws. 2 97196-- (10) No mains shall be extended outside the Urban Service Area, except as may be necessary to serve the property within the Town or upgrade service to existing customers, without the prior express written consent and approval of the Board of Trustees. 21-1-102. Reimbursement Policy and Procedure (1) Reimbursement for Line Extension Through Undeveloped Property. In accordance with the Comprehensive Plan development is encouraged in areas directly adjacent to the Town. In the event a development is not located adjacent to the Town a developer may find it necessary to install a water or wastewater lines through undeveloped property to obtain service. Such person may request the establishment of a reimbursement agreement to recover a portion of the line installation costs from subsequent future development along the line. (a) The establishment of a reimbursement agreement is optional and must be requested by the developer prior to construction of the line. (b) The developer shall obtain three independent written quotes or bids for the line. The lowest bid shall be the basis for establishing a reimbursable amount, regardless of whether the low bidder performs the work or not. The quotes or bids shall be obtained for doing the work in a reasonable but not an accelerated time period. (c) The reimbursable amount shall not be increased or decreased to reflect fluctuations in construction costs and shall not be increased for interest nor decreased for depreciation. The date of the construction quote or bid shall establish the initial index value. (d) The reimbursement agreement shall expire after a period of ten (10) years from the acceptance of the line unless extended in writing by the Board of Trustees. (e) Reimbursement payments shall be due and payable prior to the installation of any service or line extension to the undeveloped parcel. (f) If the line is installed through or adjacent to more than one property, the future developers shall pay for their proportional share based on the usage of the line generated through their property. (2) Reimbursement for Line Extension Through Previously Developed Areas. A developer may find it necessary to replace an existing undersized or otherwise inadequate line to obtain service. The developer may be eligible to establish a reimbursement agreement in the following cases: 3 971968 (a) If a property adjacent to the replacement line had a tap on the original undersized line and is later subdivided the developer of this second property shall reimburse the original developer an amount determined pursuant to the provisions of this ordinance. To be eligible for such reimbursement the developer must establish a reimbursement agreement as provided in Section (1). (b) If the line to be replaced is in such a condition or configuration that it would in the opinion of the Town Administrator be eligible for replacement, the Town may pay the portion of the cost that it would incur to replace or upgrade the line as calculated, subject to fund availability. Such Town participation shall be administered in accordance with Section (3). (3) Reimbursement for Major Structures. A developer may find it necessary to install a major structure to obtain water or wastewater service. The developer may be eligible to establish a reimbursement agreement. (a) A reimbursement agreement may be established if the major structure is a component of the water distribution or wastewater collection system that will bring direct benefits to an identifiable area. Examples are: 1. Wastewater lift stations 2. Water booster pump stations 3. River or highway crossings (b) The cost of the utility line or structure required by the project itself shall be paid by the Developer. The cost of the remainder of the utility line required by the Town shall be paid by the Town. (c) To be eligible for reimbursement, the developer shall establish a reimbursement agreement as provided in Section (2). 21-1-103. Line Oversizing Policy (1) General. The purpose of the line oversizing policy is to enable a developer to recover the costs incurred to install an oversized water or wastewater line. The "oversized" portion is the difference between the line size required by the property and the line size required by the Town to meet future growth demands. The developer is required to bear the full costs for installing 8" wastewater lines, or larger if required to serve that development, and for installing all water lines 6" in diameter, or larger if required to serve that development. 97196e (2) Line Sizing. The actual size of the water or wastewater line required shall be initially established by the developer with supporting documentation to verify that the sizes of the water or wastewater lines or both, meet the Town's specifications. Final evaluation and design shall be determined by the Town. Criteria to be used for this determination shall include, but shall not be limited to the following: (a) Utility Master Plan requirements. (b) Potential future demand on the water or wastewater system as related to the proposed development. (c) Hydraulic design criteria of the water or wastewater system. (3) Town Participation in Oversizing Project. The Town may require a developer to install an oversized water or wastewater line. If an oversized line is required, the Town will participate in the project costs if the oversizing is required to provide service to the Town's existing customers. (4) Developer Reimbursement. When the Town requires a developer to oversize either water or wastewater lines to meet the needs of anticipated development the developer may request the Town to enter into a reimbursement agreement. The agreement may provide that the developer will be reimbursed the cost of the required oversizing from future developments which make use of the oversizing. The reimbursement agreement shall expire upon repayment to the developer of the oversizing costs or the expiration of 10 years from the completion of the installation. (5) Determination of Eligible Project Costs. (a) Only those components of the water or wastewater line project that are specifically related to the oversizing shall be included for oversizing participation. Eligible costs include those costs to furnish and install the oversized pipe, fittings, valves and service saddles. The costs for design, installation, service lines, manholes, surface repairs and connected lines and appurtenances are not eligible. Wastewater manholes will be included if larger than a 4 -foot diameter manhole is needed because of the wastewater line size. (b) Construction Quotes. If the developer is aware that there will be oversizing required and that the cost of the oversizing is less than $5,000, the developer shall obtain a minimum of three written quotes from qualified contractors for construction of the oversized line. The quotations shall be based on construction of the line in a reasonable but not an accelerated time period. The Town and the developer shall agree on a reasonable time frame to be included in the request for quotations. The lowest quote shall be the basis for determining eligible oversizing costs. 5 971968 (c) Competitive Bids. If the cost of the oversizing is estimated to be greater than $5,000, the developer shall obtain competitive bids for the construction of the oversized line, in accordance with the State laws and Town procedures for capital projects. The bids shall be based on construction of the line in a reasonable but not an accelerated time period. The Town and the developer shall agree on a reasonable time frame to be included in the request for quotations. The Town and the developer have the right to reject any and all bids, for cause. (d) Determination of Final Costs. The developer's engineer shall submit to the Town a summary of the final eligible project costs. The final costs shall be based on the lower of the actual installation costs or the bid received for the project. (6) Water and Wastewater Development Agreement. If the Town agrees to participate in an oversizing project the developer shall prepare a Water and Wastewater Development Agreement which will include: (a) An estimate of the oversized line project costs, prepared by a Professional Engineer. Itemization of the cost estimate shall be attached to the agreement. (b) Distribution of project costs between the Town and the developer. (c) Time schedule or phasing plan(s) which the developer agrees to comply with. (d) Any reimbursement agreements between the developer and future developers along the oversized line. (e) The Water and Wastewater Development Agreement shall be reviewed and signed by the Utility Superintendent, the Town Attorney, and the Developer. 21-1-104. Effective Date: The Board of Trustees of the Town of Berthoud herewith fords, determines and designates that this Ordinance shall take effect and be in force thirty (30) days after publication. At its meeting July 26, 1994, a public hearing was set by the Board of Trustees of the Town of Berthoud for its meeting held on the 9th day of August, 1994. After the public hearing, the Ordinance was read, passed and ordered published by the Board of Trustees at its meeting this 9th day of August, 1994. 971968 TOWN OF BERTHOUD: chard Strachan Mayor ATTEST: Mary K. Cow in Town Clerk Published: 8-11-94 7 971.9+' APPENDIX A WASTEWATER TREATMENT MASTER PLAN UPDATE (MWE, May 1996) 971968 (9016) WAS us A TIVIEWS DATE WN 0OP L3 MOM 971968 MOM 3S McLaughlin Water Engineers, Ltd. 2420 Alcott Street, Denver, Colorado 80211 (303) 458-5550 Facsimile (303) 480-9766 103060,1344 ® compuserve.com May 17, 1996 Mr. Richard Strachan, Mayor Board of Trustees % Anna Lenahan, Manager P.O. Box 1229 Berthoud, Colorado 80513 RE: Letter of Transmittal — Wastewater Treatment Master Plan Update Ladies and Gentlemen: Submitted enclosed is our Master Plan update for the Berthoud wastewater treatment facilities. RONALD MELAUGHLIN LEON ELSE: HALFORD E ERICKSON WILLIAM R KENDALL RALPH L TOREN TERRENCEP KENYON RICHARD E MCLAUGHLIN RONALDI MCLAUGHLIN GENE A BURRELL MICHAEL E MERCER )OHN N PPLAUM MICHAEL R GALUZZI SCOTT E LEHMAN BRIAN S KOLST AD G DEAN DEROSIER EDWARD D BAIN BRIAN I CHEVALIER DANIEL F. ELAHA ). HAROLD ROBERTS LEANDER L URN,' DANIEL N. PETRAMALA RONALD D LUCERO A proposed initial capital improvements program has been developed; it resolves the immediate problem of inadequate sludge treatment capacity — and also provides additional wastewater flow treatment capacity so that the present plant can be utilized for a few more years. All major investment should be made at the proposed permanent regional plant site, located about L/ -mile downstream. We will be available to review this report with you at your request. Respectfully su Ronald C. Enclosures ASPEN, CO, ?PO 7a -E920 OF60e Christopher K. Gulden 971968 RCM:d92-008.003P/RCM•J PHOENIX, AZ (6021248-7702 DMPLETE ENGINEERING SERVICES IN WATER RIGHTS AND RESOURCES WATER TREATMENT AND DISTRIBUTION SUBSURFACE DRAINAGE IRRIGATION FOUNTAINS STORM DRAINAGE AND FOOD CONTROL WASTEWATER COLLECTION TREATMENT ANIREUSE FIRE PROTECTION WATER BASEDRECREATION SPECIALTY HYDRAULICS RATE STUDIES AND UTILITIES ECONOMICS SECTION I INTRODUCTION BACKGROUND Regional wastewater master planning has been previously undertaken by the Town. The Wastewater Service Area Plan, by the Engineering Professionals, Inc. dated December 1995, defined Berthoud's future service area. The Plan also predesigned a trunk sewer network that would collect sanitary sewage flows from development in the service area. In addition to the designated service area, Berthoud treats, by contract, wastes from the South Loveland Sanitation District. The Plan was adopted by the Town as a master plan guideline for the sanitary sewage (wastewater) utility. As recommended by the Plan "...this study should be amended as development warrants." The Wastewater Service Area Plan concluded that significant expansion of capacity could not take place at the existing plant site; also that the existing site is not strategically located to serve the proposed service area by gravity. New State/Federal regulations regarding sewage sludge treatment and disposal (the "503 Regulations") became effective in 1995. Preliminary plant evaluation by MWE personnel indicated that the existing sludge facilities are inadequate, and that near -future capital improvements will be needed. The Town is experiencing continuing growth. Some older sewers have had heavy inflow/infiltration (I/I) problems. During wet periods, actual flows have exceeded nominal plant capacity. Even considering only average loads, the plant capacity would have to be increased within a few years. PURPOSE The purpose of this study is to formulate an optimum plan for the next phase of treatment improvements. Specifically, to be resolved are: a. Revised estimates of ultimate and 10 -year to 20 -year growth projections. b. Select the best regional plant site to be acquired. 92. 8.003P:SrP-RPT 971968 c. Define, at a conceptual level, the components to be included in an initial phase Capital Improvement Program — probably consisting of: • plant site acquisition • trunk sewer from present plant to new site • required sludge treatment improvements for existing and design period loads • additional capacity needed for near -future growth 92-008.003P:SrP-RPP I-2 971968 SECTION II DESIGN FLOWS SERVICE AREA The proposed study/service area was established in the 1985 Report, as shown on Figure 2 of that report. Except for area in Weld County, this is slightly smaller, but nearly coincidental with the "Berthoud Planning Area" as presented in the Town of Berthoud Land Use Plan, prepared by BHA Design, Inc., dated May 1994. The Land Use Plan also defines an Urban Growth Management Area — which represents areas thought to develop in the next 10 to 20 years. It is probable that most of the trunk/collection sewers constructed in the next 20 years will be to serve this area. PRESENT LOADS Existing customers include: 156 Business/Commercial taps in Berthoud 1422 Residential taps in Berthoud 1578 Total Sewer Customers in Berthoud 6 Business/Church taps in South Loveland District 579 Residential taps in South Loveland District 585 Total Sewer Customers in South Loveland District Sewage flows have been erratic, primarily due to infiltration problems in both the older area of Berthoud and in the South Loveland District. From present population estimates in Berthoud (3800), it is reasonable to use a design value of 2.8 persons per residential tap. Normal design sewage loads per residential tap would then be: 210 gpd/tap 0.56 lb BOD5/day/tap 92-008.003P:STP-RPT 971968 Since the commercial component is not large nor unusual, the assumption of similar loads from commercial taps will result in only minor error. Accordingly, predicted present design sanitary sewage flows for 2163 taps is 454,000 gpd and 1211 lbs BODS/day. Flow records of February and March, 1996, show a low influent flow of 363,000 gpd. The average for February was 490,000 gpd, and most day's flows were in this range. For practical purposes, base unit sewage flow of 230 gpd/tap can be used. BODS measurements indicate variable, but lower strength wastes than predicted above. However, BODS measurements are tabulated from randomly collected samples, and not proportionately composited; it is therefore recommended that the 0.56 lb/day BODS unit load be retained for design purposes. Reported influent flows have been over 1.0 MGD during wet weather (1.21 MGD in May 1983, per 1985 Area Plan). However, infiltration/inflow (I/I) is expected to be reduced significantly due to corrective work in Berthoud and South Loveland. Further installation of new sewers should be conducted so as to result in negligible incremental infiltration. PROJECTED LOADS Based on the above, information from the Area Plan, and our plant capacity analyses (see later), a fixed allowance for I/I of about 400,000 gpd is a reasonable practical assumption. Berthoud planning information is that a 21 %/year annual growth rate is a best estimate for the next few years. Service area growth projections made in the 1985 Area Plan indicate an ultimate service area population of about 70,000 people, with a predicted maximum daily flow of about 9 MGD. It is our opinion that the actual flows will be less because: • water availability may limit total development. • recent emphasis on water conserving fixtures will reduce unit flows, as compared to those experienced in 1985. • saturation buildout of all of the service area is unlikely within a reasonable planning period (say 100 years). 92-O38.003P:STP-RPT II -2 971968 Recommended design criteria for use at this time include: Year 1996 2000 2010 Ultimate 92-008.003P:SIP-RPT Daily Sanitary Sewage Flows 490,000 gpd 540,000 gpd 700,000 gpd 11-3 Maximum Acceptable I/I 400,000 gpd 350,000 gpd 300,000 gpd 890, Nominal Design Flows pd ,000 gpd 1,000,000 gpd 971968 SECTION III PLANT SITE SELECTION GENERAL The existing site is not strategically located to receive a majority of flow from the service area by gravity. The available site area is limited , and does not provide sufficient area for expansion. Further, the present plant facility was not planned for expansion — and the process used is not conducive to enlargement. As stated in the 1985 Area Plan, it can be concluded that a new site should be acquired for a Berthoud area sub -regional scale plant. The Area Plan indicated a proposed plant location on the north bank of the Little Thompson River, just east of the Latimer County boundary. However, our field investigation indicated that this specific location did not provide a good site. Four alternative sites were located by field reconnaissance. These are identified on the attached map and described below. ALTERNATIVE PLANT SITES Four additional sites were investigated as possible candidate locations for relocating the plant facility. Site name, boundary, and features are provided as follows: Site N2 1 - This is the site indicated in the 1985 Area Plan. It is located in Weld County, just north of the Little Thompson River. Field check indicated minimal land availability without extensive excavation. Site N2 2 (Carol Property) - Area bounded by Weld County Road i to the west, County Road 6C to the north, farmland to the east and south; site is in Section 19 on the Berthoud U.S.G.S. map, entirely inside Weld County. The site is on large flat area, and is presently used as farm land. No existing structures are on the privately owned property. Approximate site elevation - 4930 feet. 92-008.003P:STP-RPr 971968 Site N2 3 (Kraft Property) - Area bounded by Weld County Road on the east, and County Road 6C on the south, the Little Thompson River on the north and west; site is in Section 24 on the Berthoud U.S.G.S. map, entirely inside Larimer County. The site is located on a flat area, and is a privately own property used as farmland, with a house in the northeast corner. Approximate site elevation - 4935 feet. Site N2 4 (Sullivan Property) - Area bounded by Weld County Road on the east; County Road 6C on the north; the Little Thompson River on the west; and adjacent farmland on the south. The site is in Section 24 on the Berthoud U.S.G.S. map, entirely inside Larimer County. The site is a predominately flat privately owned farm, with a house and two barns in the center. Approximate site elevation - 4935 feet. Site N2 5 (Beefus Property) - Area bounded by County Road 6C on the north and the Little Thompson River on the east and south; site is in Section 24 on the Berthoud U.S.G.S. map, entirely inside Larimer County. The site is predominately farmland with a mild pitch to the southeast, and has no structures on the property. Approximate elevation - 4950 feet. PRELIMINARY SITE SELECTION All five sites are located near or adjacent to the Little Thompson River. Flood plain location became an immediate issue. The four new sites were initially chosen through topographical rationale, which attempted to maximize the gravity sewer collection area for a new plant location in conjunction with the Town of Berthoud growth Area Plan. The U.S. Army Corps of Engineers, Omaha, Nebraska, June 1977, Flood Plain Study on the Little Thomson River was reviewed. The accuracy of the study may be reduced due to additional development/urbanization of Little Thompson River drainage basin area since the time of the study. However, additional or more recent flood plain analysis was not justified due to the findings in the Corps of Engineers study. The study also includes 500 year Flood Plain delineation, but this is not usually a consideration for the site selection. The Corps of Engineers study terminated along the Little Thompson River at the Weld County line. Approximation of the flood plain location just inside Weld County was inferred from the area topography. Of the five candidate sites, only Site N2 1 and Site N2 5 (Beefus property) were not located in the 100 year Flood Plain. This is shown on the attached map. Site N2 2 (Carol property), although not in the study area 92-008.003P:STP-RPT 111-2 9719£8 of the Flood Plain analysis, would clearly be in the 100 -year boundary due to the mean elevation of the site. In addition to being above the flood plain, Site N2 5 (Beefus property) has the following additional qualities: ► Close to existing STP (approximately 1 mile) - minimizes new trunk sewer length. ► North of the Little Thompson River - eliminates sewer line crossing of River. ► Close to Little Thompson River - minimizes plant outfall capital costs ► No existing structures on property ► Adequate area - suitable for expandable plant, possibility for on -site beneficial reuse. ► Regional location - ability, at some point in the future, to receive sewage flow from three near -by lagoon type STPs (River Glenn, Berthoud Estates, Vaquero & Western Mini), as well as nearly all of the study area, by gravity flow. Further analysis of the Beefus property should include subsurface conditions. A geotechnical soils investigation and report would provide further STP site feasibility information. 92{g8.003P:SrP-RPF III -3 971.968 SECTION IV PRELIMINARY DESIGN PHASE 1 IMPROVEMENT PROGRAM GENERAL The wastewater master plan is a guideline for the long-term development of the wastewater utility system. However, this system is intended to serve a large area which will be developed over many years — and, for economic reasons, must be constructed in phases as needed. Ideally, to minimize the risk of over -building and to reduce the time related costs of investment (i.e. interest and depreciation), the facilities should be constructed in discrete practical increments, keeping pace with the development rate. The intent of this report is to develop preliminary designs and a budget for Phase 1 of the improvement program. Conclusions from analyses and review of the Master Plan, which affect identification of Phase 1 include: 1. The existing plant site is not well suited nor adequate for use as a regional site for the Berthoud service area. The permanent plant should be developed and expanded at a different site; therefore, no significant capital investment should be made at the existing location. 2. The existing plant has capacity to handle approximately 0.8 MGD of normal strength sanitary sewerage plus some infiltration, provided minor treatment improvements are made to existing plant. Although the plant has been overloaded hydraulically, rehabilitation of the sewer system should be able to reduce infiltration inflows so that the main processes of the existing plant have sufficient capacity for a few more years (approximately 10 years at a 2.5 percent per year compounded growth rate). 3. The weak link of the existing plant is the sludge treatment and disposal facilities. The existing sludge digester is totally inadequate and there are no sludge thickening or dewatering facilities with the exception of small sand drying beds. 4. There is an imminent proposed development to the east which would require pumping of collected sewage to the existing plant site. 92408.003P:STP-RPr 971968 PROPOSED PHASE 1 PROGRAM The following capital improvements are recommended to be included in the Phase 1 Program, which is intended to resolve existing problems and to be carried out in the 1996-1997 time frame. A schematic is enclosed for illustrative purposes. 1. Acquire Site for New Regional Plant It is proposed to acquire an approximate 15 -acre plant site. The best location is alternative N2 5 which is shown on the attached map. The location of this site appears to be ideal; and it is in keeping with the intent of the 1985 Plan. 2. Construct An Aerobic Sludge Digester at the New Regional Plant Site This digester would be located and sized so as to be part of the permanent ultimate treatment facility. In addition it is proposed to install a centrifuge in conjunction with the digestion facility. The initial centrifuge would be piped and designed to serve two functions i.e. (a) thicken waste activated sludge before digestion, and (b) dewater waste digested sludge before beneficial use type land application. The digester should be sized to be compatible with a treatment plant capacity of approximately 1.0 MGD. Multiple digesters would be planned as the plant is expanded beyond that rate. The digester should be designed to permit possible conversion to the anaerobic process in the future. 3. Connecting Pipelines Construct a 24- inch trunk sewer leading from near the existing plant site to the new plant site, approximately 2,930 lineal feet. This sewer should probably be sized at the ultimate projected capacity as shown by the master plan; however, its Phase 1 use would be merely to transport waste activated sludge from the plant to the new site, and therefore it could be installed at a much smaller size, if so dictated by availability of capital. Parallel to the trunk sewer would be constructed a 4 -inch force main. This force main would be utilized during Phase 1 to transmit centrate and wastes from the new plant site back to the existing plant for treatment. 4. Lift Station/Wet Well A pumping station should be constructed at the permanent plant site for interim use. This station would be used to pump centrate and supernatant from the centrifuge and digester back to the existing plant for treatment. It could also be used to pump waste from the east side of Town development areas which would be delivered to the new site by gravity. The pump station would return the flows to the existing plant site through the 4 -inch force main described in item 3 above. 92-008.W3P:STP-RPT IV -2 971968 5. Existing Plant Upgrade It is our opinion that the existing plant can be upgraded for additional capacity and reliability at minimal cost by converting either the existing primary clarifier or the digester for use as a sludge reaeration basin. This would require the installation of aeration equipment in the basin, with piping connections so that return activated sludge can be directed to this basin prior to returning to the oxidation ditch. Although resulting actual capacity should be verified by field testing, it is probable that this improvement will increase the plant capacity to approximately 0.7 MGD of sanitary sewage. These improvements will reduce the potential of odors at the existing plant site both by increasing biological treatment efficiency and oxygen transfer capacity; and due to the fact that no sludge will be treated at this site. Refer to the enclosed preliminary work schedule for time relations to the above described improvements. PRELIMINARY COST ESTIMATE The following cost estimates are based on preliminary designs and are intended to be adequate for policy determination and preliminary budgeting only. We have provided approximate costs for the physical facilities. To this must be added the acquisition cost of the plant site; it is recommended that an appraiser be retained for that purpose, and to assist with acquisition procedures. 1. NEW TRUNK SEWER AND FORCE MAIN A useful life cost analysis for sizing the trunk sewer: Pipe Size Installation Design Design Years* Diameter Cost Estimate Peak Flow Flow Of (Inches) Per (L.F.) (MGD) (MGD) Service 15" $40 2.11 0.84 7 18" $48 3.4 1.36 12 21" $55 5.1 2.04 43 24" $63 7.9 3.16 60 *Years of service based on existing STP flow rate of 0.7 MGD and Town growth rate of 244% 92-008.003P:SrP-RPT IV -3 971968 It is recommended that a 24 -inch trunk sewer be installed as to comply with standard design criteria, in terms of number of useful service years. The actual useful life of the sewer will depend upon regional growth of the area. The 1985 Area Plan Report, with the new STP being located at Site N2 1, planned to convey future sewage flows from the Champion area and new development areas northwest, north, northeast, and east of Berthoud — all towards the eastern edge of the total growth plan area. With the new STP site location (Site N9 5), it is recommended that sewage collection master planning be re-evaluated for the above mentioned areas. To minimize initial capital costs, a 6 -inch gravity sewer could be selected to convey sludge from the existing STP to the new trunk sewer. As part of the initial phase capital improvements, a 4 -inch force main is required to transfer centrate, generated by the sludge dewatering facility, back to the existing STP. CONSTRUCTION COST ESTIMATES a. 24 -Inch PVC Trunk Sewer b. 6 -Inch PVC Conveyance Sewer c. 4 -Inch DIP Force Main d. Manholes (9) $ Installed $185,000 60,000 80,000 20,000 2. SLUDGE PROCESSING FACILITY Initial phase capital improvements include: ► Covered, insulated, 300,000 gallon aerobic digester, with aeration equipment, sludge pump, and process piping. ► Heated sludge thickening and dewatering building complete with centrifuge, truck bay, operations room, and polymer feed system. ► Concrete wet well pump station with 2 submersible return flow pumps. ► Concrete aerated sludge receiving tank with aeration equipment, sludge grinder and lift pump. 92.008.003P:SIP-RPr IV -5 9'71.968 CONSTRUCTION COST ESTIMATE: $850,000 3. EXISTING STP IMPROVEMENTS/MODIFICATIONS a. Conversion of old primary clarifier to sludge reaeration basin - to include aeration equipment and yard piping. b. Conversion of existing sludge digester to aerated sludge holding tank - to include replacement of aeration equipment. COST ESTIMATE: $50,000 4. POWER UTILITIES BROUGHT TO NEW PLANT SITE Quote from Poudre Valley REA - Electricity Public Service Company Natural Gas (Limited supply within '/ mile) SUMMARY $15,000 N/A As the Town of Berthoud continues to experience population growth, the capacity of the sewage treatment plant will rapidly approach design limits. The plant is currently overloaded as to the ability to process sludge. In addition, the plant site is not well located to collect sewage flows by gravity from planned development areas. As provided in the 1985 Area Plan Report, a new plant site was selected and sewer trunks master -planned relative to that location. This Master Plan Update re-examines the site location, along with four others, and concluded that site N2 5 (Beefus Property) is best suited for locating new sewage treatment processes. Additional site surveying and geotechnical investigation is needed to conclude this selection. A phased build-up plan is suggested for capital improvements at the new site. Phase 1 includes: 1) construction of a sludge process facility at the new plant site, 2) trunk sewer and force main pipelines installed to connect the existing and new site, 3) improvements/upgrades made to the existing plant processes. 92. 8.003P:STP-RPr IV -6 971968 The preliminary estimate for the capital budget for the recommended initial phase is: 24" trunk sewer 4" force main Site Application Sludge treatment facilities (at new plant site) Improvements to existing plant Subtotal, Estimated Construction Costs Add 25% for contingencies, engineering, and miscellaneous Total Estimated Project Budget* *Plus land acquisition costs (not estimated herein) $ 205,000 80,000 10,000 850,000 50.000 $1,195,000 299 000 $1,494,000 With a normal growth rate, it is probable that the existing plant, modified as proposed herein, will have adequate capacity for 5 to 10 more years. 92-006.003P:STP-RPT IV -7 971.968 APPENDIX B POTABLE WATER WELLS (State Engineers Office) 971968 REPORT DATE 06/30/97 PERMIT D CO OWNER INFORMATION COLORADO WELLS, APPLICATIONS, AND PERMITS PAGE 1 COLORADO DIVISION OF WATER RESOURCES ACTIVITY STATUS 1ST USED ANNUAL ACRES GEOL WELL WELL WATER SEC LOCAT'N TOWN P CD DATE CD DATE WD MD DB USE DATE APROP IRR AQFR YIELD DEPTH LEVEL COORDINATES QTRS SC SHIP RANGE M 6649R 1 62 WILSON CHAS W BERTHOUD, CO 80513 4 1 119G 1 62 SCHMECHEL DOUGLAS 19993 WELD CNTY RD 5 BERTHOUD, CO 90513 NP 09/25/90 4 G C GW 10570F 1 62 CARROLL HALLEY & MARY F RT 1 BERTHOUD, CO 80513 4 1 03/24/66 10649F 1 62 CARROLL MARY F & HALLEY RT 1 BERTHOUD, CO 80513 4 1 03/28/66 11060R 1 62 CARROLL HALLEY & MARY F RI 1 BOX 23 BERTHOUD, CO 90513 4 1 09/11/36 360.00 43 10 NWNE 30 4 N 68 W S 11060R R 1 62 CARROLL HALLEY & MARY FERN 19858 WCR N1 BERTHOUD. CO 80513 NP 04/16/93 4 1 GW 300.00 40 7 0143N,26305 NWNE 30 4 N 58 W S , 10650F 1 62 CARROLL HALLEY & MARY E RI 1 BERTHOUD, CO 80513 4 1 04/06/66 1000.00 42 7 NWNW 30 .4 N 6E W S 161668 1 62 MACDONALD SAM 19417 WCR 3 BERTHOUD, CO 80513 NP 07/17/91 AS 05/28/92 4 8 GW .5.00 22 19805,0375E NESE 30 4 N 6E W S 161668 A 1 62 MACDONALD SAM 19417 WCR 3 BERTHOUD. CO 80513 NP 07/17/91 WA 4 8 GW 5.00 150 12 1980S.0200E NESE 3C4 4 N 68 W S 135343 1 62 REINKING R 0 LONGMONT, CO 80501 NP 04/13/84 4 89 SWSE 31 4 N 66 W S 500.00 35 14 NESW 26 4 N 68 W S 200 0500E,0050N NENE 29+ 4 N 68 W S 600.00 43 7 NWNE 30 4 N 68 W S 400.00 41 7 NWNE 30 4 N 66 W S 971%8 REPORT DATE 06/30/97 PERMIT D CO OWNER INFORMATION ACTIVITY STATUS COLORADO WELLS, APPLICATIONS, AND PERMITS PAGE 1 COLORADO DIVISION OF WATER RESOURCES CD DATE CD DATE WD MD DB USE DATE APROP IRR AQFR YIELD DEPTH LEVEL COORDINATES OTRS SC SHIP RANGE M 1ST USED ANNUAL ACRES GEOL WELL WELL WATER SEC LOCAT'N TOWN P 10797 1 62 WAGNER C 0 WESTERN SPG, IL 00000 4 9 03/08/62 91404VE 1 62 STARCK ROBERT 21746 WD CO RD 13 BERTHOUD, CO 80513 AV 10/02/91 4 9 GW 2S00S,1400W NESW 18 4 N 68 ,+f 5 .60483 1 62 STARCK ROBERT P 21746 WD CO RD 13 BERTHOUD. CO 80513 NP 06/07191 AB 09/20/91 4 9 L OW 25.00 240 15 25005,1400$ NESW 18 4 N 68 W S 60483 A 1 62 STARK ROBERT P 21746 WCR 13 BERTHOUD, CO 80513 NP 11/01/91 WA 4 9 L OW 20.00 240 12 2500S,1450W NESW 18 4 N 68 W S 4639 1 62 COOK ROBERT R F D BERTHOUD, CO 80513 4 8 10/21/59 6.00 77 19 SW$W 18 4 N 68 W S 10709R 1 62 CARROLL MARY F & HALLEY RT 1 BERTHOUD, CO 80513 4 1 400.00 46 15 NWSE 19 4 N 68 W S 20385F 1 62 SULLIVAN TIMOTHY ROUTE 1 BOX 40 BERTHOUD, CO 80513 4 1 07/11/77 14.00 200.00 46 8 00305,2620E SWSE 19 4 N 68 W S 10708R 1 62 CARROLL MARY F & HALLEY RT 1 BERTHOUD, CO 80513 4 1 400.00 46 15 NESW 19 4 N 66 W S 36243 1 62 OLSON GARETH R 6840 S HARRISON ST LITTLETON, CO 80122-2052 NP 02/22/95 4 9 L OW, 24005,06505 NESE 20 4 N 58 W S 33442 A 1 62 SCHAAL D BERTHOUD, CO 80513 NP 09/01/77 4 8 11/15/85 SWSW 20 4 N 68 W S 1954R R I 62 SCHAAL DALE & MAX RT 1 BOX 84 BERTHOUD, CO 80513 NP 12/02/91 SP 07/22/92 4 1 OW 250.00 51 12 07005,0840w SWSW 20 4 N 68 W S "'54R 1 62 SCHAAL DALE H & MAX N RT 1 BERTHOUD, CO 80513 4 1 02/08/78 210.00 175.00 47 15 0700$,0460W SWSW 20 4 N 68 W S .1875 1 62 SCHAAL DALE RT. 1, BOX 84 BERTHOUD, CO 80513 4 8 03/19/76 1.00 15.00 50 13 0325S,1215W SWSW 20 4 N 68 W S 3442 1 62 SCHAAL DALE & MAX RT. 1, BOX 84 BERTHOUD, CO 80513 4 8 08/09/77 1.00 20.00 45 10 02145,0096W SWSW 20 4 N 68 W S 1371 R 1 62 RAINBOWS END R SCOTTSDALE, AZ 85251 NP 08/10178 4 1 NWSW 21 4 N 68 W S 7.00 43 NENW 17 4 N 68 W S 971968 REPORT DATE 06/30/97 COLORADO WELLS, APPLICATIONS, AND PERMITS PAGE 1 COLORADO DIVISION OF WATER RESOURCES PERMIT D CO OWNER INFORMATION ACTIVITY STATUS 1ST USED ANNUAL ACRES GEOL WELL WELL WATER SEC LOCAT'N TOWN P CD DATE CD DATE WD MD DB USE DATE APROP IRA AQFR YIELD DEPTH LEVEL COORDINATES QTRS SC SHIP RANGE M 154204 1 35 LINK DICK 2702 W EISENHOWER BLVD LOVELAND, CO 80537 NP 05/15/89 4 9 5122 1 35 APPLEBY H A LOVELAND, CO 80537 4 8 02/16/60 102637 1 35 GOULD MARGARET T 2520 ELDRIDGE CIR GOLDEN, CO 80401 NS 4 89 02/13/79 GW 2.00 300 15 0300S,2100W SESW 12 4 N 69 W S 1.00 81 6 SESW 13 4 N 59 W 5 GW 1.00 430 20 0800N,0100W NWNW 14 4 N 69 W zS 971268 REPORT DATE 07/02/97 COLORADO WELLS, APPLICATIONS, AND PERMITS PAGE 1 COLORADO DIVISION OF WATER RESOURCES PERMIT D CO OWNER INFORMATION ACTIVITY STATUS 1ST USED ANNUAL ACRES GEOL WELL WELL WATER SEC LOCAT'N TOWN P CD DATE CD DATE WD MD DB USE DATE APROP IRR AQFR YIELD DEPTH LEVEL COORDINATES QTRS SC SHIP RANGE M 107396 1 35 BROWER LLOYD V JR 222 MINNIE ILA LN BERTHOUD, CO 80206 NP 04/04/79 4 H 1 35 LEWIS STAN BOULDER, CO 80301 AP 06/09/86 AU 07/23/86 4 B 10.00 380 28 2456S,1835E NWSE 24 4 N 69 W S OW NWSE 24 4 N 69 W S 83647 1 35 DEVRIES RICHARD RT 4 BOX 108 LONGMONT, CO 80501 NP 04/14/76 4 H 05/19/76 1100 15.00 50 27 2100S,2130E NWSE 24 4 N 69 W S 88446 1 35 DIEPERSLOOT PETE J & IDA M 333 MINNIELLA LN RR2 BERTHOUD, CO 80513 LOT 2 DIEPERSLOOT EXEMPTION NP 01/31/77 4 H 04/30/77 2.00 50 20 1700S,2230E NWSE 24 4 N 69 W S 92471 1 35 SCHRA MARVIN D 247 MINNIE ILLA LN BERTHOUD, CO 80513 NP 07/28/77 4 H 11/24/77 8.00 80 16 2300S,2350E NWSE 24 4 N 69 W S 971968 APPENDIX C BERTHOUD WWTP COMPREHENSIVE PERFORMANCE EVALUATION (Environmental Science Department Red Rocks Community College May 1996) 971968 THE CITY OF BERTHOUD, COLORADO COMPREHENSIVE PERFORMANCE EVALUATION MAY, 1996 971968 Berthoud, Colorado Comprehensive Performance Evaluation May, 1996 INTRODUCTION A Comprehensive Performance Evaluation (CPE) was conducted for the wastewater treatment plant of the City of Berthoud, on the 9th, 10th, and 13th of May, 1996. The evaluation was conducted by an EPA 104(g)(1) Outreach Trainer from the Environmental Science Department, Red Rocks Community College. Comprehensive Performance Evaluations are conducted on wastewater treatment facilities as a means of assessing whether factors associated with the administration, design, operation, or maintenance are affecting the optimal performance of the facility as related to effluent quality. The CPE is a performance evaluation tool used by the Water Quality Division to periodically assess the capability of wastewater treatment plants in Colorado. The CPE is based on the EPA Handbook: Retrofitting POTWs. The CPE is the first step in a two step process and is conducted to provide information for POTW administrators to make decisions regarding efforts necessary to improve performance. The primary objective is to determine if significant improvements in treatment can be achieved without major capital expenditures. The objective is accomplished by assessing the capability of major unit processes and by identifying and prioritizing those factors that limit performance and which can be corrected to improve performance. The second step of the process is called a Composit Correction Program (CCP) and represents the performance improvement phase. It is a systematic approach to eliminating those factors that inhibit performance in existing POTWs. The CCP focuses on optimizing the capability of existing facilities to perform better. Evaluation of Major Unit Processes Major unit processes are evaluated to assess their potential to achieve desired performance levels. If the CPE indicates that the major unit processes are adequate or potentially adequate, a major plant expansion or upgrade may not be necessary and a properly conducted CCP should be implemented to achieve optimum performance. If, on the other hand, the CPE shows that major unit processes are inadequate, owners should consider modifications of these processes as the focus for achieving desired performance. Results of evaluation of major unit processes can be summarized by categorization of plant type, as illustrated below. 971968 t Type 1 plants are those POTWs where a CPE shows that current performance difficulties are not caused by limitations in the size or capabilities of the existing major unit processes. Type 2 plants are those POTWs where a CPE represents a situation where the marginal capacity of major unit processes will potentially prohibit the ability to achieve the desired performance level. Type 3 plants are those POTWs in which existing major unit processes are inadequate. Although other limiting factors may exist such as the operators' process control capability or the administration's unfamiliarity with plant needs, performance cannot be expected to improve significantly until physical limitations of major unit processes are eliminated. Performance - Limiting Factors In almost all CPEs, several factors are identified as limiting performance. After these factors have been identified, they are prioritized as to their adverse effect on achieving desired plant performance. The purposes of this prioritization are to establish the sequence and/or emphasis of the follow-up activities necessary to , achieve compliance. If the highest ranking factors (i.e., those having the most negative impact on performance) are related to physical limitations in unit process capacity, initial corrective actions are directed toward defining plant modifications and obtaining administrative funding for their implementation. If the highest ranking factors are process control orientated, the initial emphasis of follow-up activities would be directed toward plant -specific operator training. The classification system for prioritizing performance -limiting factors are listed below. Rating Adverse Effects of Factor on Plant Performance A Major effect on long-term repetitive basis B Minimum effect on routine basis or major effect on a periodic basis C Minor effect Factors that are assigned an "A" are the major problems that cause performance deficiency. Factors that are assigned a "B" routinely contribute to poor plant performance but are not major problems. 971968 9- Factors that are assigned a "C" can be shown to contribute to a performance problem, but their effect is minor. FACILITY INFORMATION Berthoud's wastewater treatment facility is an extended aeration activated sludge process utilizing an oxidation ditch design. (See Figure 1) This facility is designed for an average daily flow of 900,000 gal/day and a hydraulic detention time of 21 hours. The influent sewage is primarily domestic with some industry(restaurants, various businesses) and is transmitted to the facility through a collection system that has three(3) lift stations. The effluent from the plant discharges into No Name Creek and is required to meet national secondary treatment standards. The Berthoud facility consist of the following: Headworks; Parshal Flume Influent flow meter Flow totalizer Grit & Screen Secondary Final Clarifier Disinfection Biosolids Oxidation Ditch Uniflow type Contact Basin Aerobic Digester Milltronics (sonar) Foxboro Digital with chart recorder Hycor Helisieve, HLS 300 .9MGD with four brush rotors, fine bubble diffusers, boat clarifier rated at .4MGD,and D.O. probe Circular with mechanical scrapers to hopper, centrifugal RAS/WAS pumps, flow totalizer with chart Baffled tank configuration, 20,000ga1s. 65,000 gallon, coarse bubble diffused, decant to ox ditch, waste to drying bed or tanker for disposal The Berthoud facility is located south-east of town and discharges the effluent through a pipe into No Name Creek. rfi Sonic Flow Meter Parshal Fkane and Helisieve Screen Aerobic Digester 65,000 gals Sludge Hauler Drying Beds two 11 ft Rotors, 15hp. ee. RAS valve to ditch Oxidation Ditch 794,000 gals Design: 900,000 geliday 1,300 lb.BOD1day Boat iffier 400,000 Magnetic Flow Meter WAS valve to dig. Effluent Sample Point NPDES 001A y otcrS 15hp. ea., 66-91 rpm, Varidrive Office, Lao, Ras/Was Amps. Final Clarifier 120,000 gals Chlorine Contact Tank NO NAME CREEK irrigation ditch Berthoud Wastewater Treatment Plant Figure 1 971968 The Berthoud facility is required to meet the following secondary treatment standards: *BOD5 30 mg/I monthly avg.; 45 mg/I weekly avg. TSS 30 mg/I monthly avg.; 45 mg/I weekly avg. *Fecal 2000/100 ml monthly avg.; 4000/100 ml weekly avg. Coliform *Maximum total residual chlorine(TRC)/day = Not greater than .5 mg/I The pH maintained between 6.5 and 9.0 standard units 85% removal of BODs and TSS In addition to these limits, the sampling program shall include the following: instantaneous influent flow sampling, daily max/monthly avg. BODs grab,monthly TSS grab, monthly fecal coliform grab, monthly pH grab,monthly total residual chlorine(TRC) grab, daily PERFORMANCE EVALUATION Plant performance is based upon the previous 14 months data (February 1995 - March 1996) generated by the plant's sampling and testing program. These data are used to represent the current operational performance relative to optimum capability. The CPE seeks to establish the plant's ability to handle current loading and to effectively remove solids from the influent wastewater stream. Influent Load Balance Hydraulic: Analysis shows 140 gallons per person per day is flowing into the treatment plant based on the population of 4200 persons. This is significantly higher than the per capita rate of 100gal/person/day standard This would indicate a possible infiltration/inflow problem, or influent meter calibration. 971968 Organic: The per capita organic loading to the plant is 0,199 pounds per person per day based on a population of 4200 and is within the 0.20 pound per person per day standard. Sludge Production Ratio The total calculated BOD mass to be removed from the plant a day is 1043 lb/day. The calculated total sludge mass to be removed is 678 lb/day based on typical sludge production of .65 lb TSS/lb BOD removed. The recorded total sludge mass removed is 383 lb/day. This calculates to be a sludge production of .37 lb TSS/Ib BOD removed, and is greater than the plus or minus 15% allowed. This would indicate that the Berthoud WVVTP is not wasting enough sludge and could cause performance problems. UNIT PROCESS EVALUATION Major unit process are evaluated to asses their potential to achieve desired performance levels. If major unit processes are found to be adequate, major plant expansion or upgrades may not be necessary. A properly conducted Composite Correction Program (CCP) can be implemented to achieve optimum performance. A CPE, however, may also indicate the need for major unit modification, if they are found to be inadequate. The Berthoud treatment plant unit processes were evaluated with respect to their capability to handle current loadings and to assess their potential capability. The current organic loading to the system was projected at all flow rates based on current influent BOD loadings with a per capita contribution of (.199 lbs. BOD/day/person) from the population connected to the sewer system. The ability of the facility to handle the current loadings was assessed and the plant was categorized Type 1, 2, or 3 as described below: Type 1 Type 2 Type 3 Unit processes are adequate Unit processes are marginal Unit processes are inadequate The results of the unit process evaluation for Berthoud WWTP indicated that the facility is a Type 3. The factor that rated the plant a Type 3 was the aerobic digester. The volume of the aerobic digester (65,000 gals) would not provide minimum hydraulic detention time(HDT) of 15 days. The calculations showed that Berthoud's HDT was only 5.1 days, this is inadequate for the reduction of solids and costly for hauling sludge. 971968 PERFORMANCE POTENTIAL GRAPH To assess the plants capability relative to various loadings a performance potential graph was used. The assessed capability of the plant to meet desired performance is depicted in Figure 2. The major treatment units and evaluation parameters are listed on the left, and a range of evaluated influent flows are listed across the top. The vertical broken lines depict both the current and the design flows to the facility. The shaded bars depict the evaluation team's rated capabilities of the plant units. When interpreting the graph it is important to remember that the projected capability represents the evaluation team's judgment concerning performance capability taking both design and operational parameters into account. This is not an engineering evaluation. PERFORMANCE - LIMITING FACTORS During the evaluation, potential performance -limiting factors in the areas of design, administration, operation, and maintenance were assessed. The factors identified were classified A, B, or C as follows: A - B - C - Major effect on short-term repetitive basis Minimal effect on a routine basis, or major effect on a periodic basis Minor effect The following A, B, and C factors were identified during the evaluation and related to achieving constant effluent compliance. (A) Design - Unit Inadequacy - Sludge Treatment (A) Operation - Applications of concepts and testing to process control (A) Testing - Performance monitoring (B) Design - Secondary - Process flexibility (B) Operation - Testing - Process control testing (NR) Design - Plant loading - Infiltration/Inflow POTENTIAL "A" FACTORS: DESIGN - Unit Inadequacy - Sludge Treatment The evaluation indicates that the type, size, shape of the sludge treatment process hinders sludge wasting capability and treatment such that performance is adversely affected. The aerobic digester is projected to be only capable of providing marginal treatment. OPERATION - Application of concepts and testing to process control 971968 1 BERTHOUD WASTEWATER TREATMENT PLANT PERFORMANCE POTENTIAL GRAPH Wastewater Flow, MGD UNIT PROCESS 0.2 0.4 0.6 0.8 0,9 1.0 i Oxidation Ditch Detention Time, hr. 95.3 47.6 31.8 23.8 21.0 19.0 (1) Organic Loading lb BOD/day 1,000 cu ft (2) Oxygen Available lb O2/lb BOD (3) Final Clarifier Overflow Rate gal/day/sq ft (4) Sludge Handling and disposal Digester Detention Time, days 15 day min (5) 2.7 5.5 8.2 10.9 12.2 13.6 5.6 2.8 1.8 1.4 1.2 1.1 84 168 253 367 379 421 15.3 7.7 5.1 (1) Ox Ditch Vol. _ .794 MG (2) Design BOD/day = 173 mg/I, Current @ 164 mg9 (3) Rotors rated @ 1.7 lb 02/ft-hr, 44 feet of rotors (4) Clarifier surface area, 2375 sq ft (5) Sludge volume, .65 lb TSSAb BOD x factor of 125 Figure 2 Current Flow (.592 MGD) Design Flow ( .900 MGD) 8 The evaluation indicates the staff is deficient in their knowledge of wastewater treatment and/or interpretation of process control testing such that improper process control adjustments are made. The estimated reported secondary sludge wasting of 383 lb/day is less than the projected wasting required of 678 lb/day. Projections are based on a typical sludge production rate of 0.65 lb TSS per lb BOD removed. The hydraulic loading reported, 592,000 gal/day, is at least 30% greater than 420,000 gal/day projected flow. This projection is based on a population of 4,200 assuming a 100 gallons per capita per day usage. This may be due to: - industrial contributions - infiltration / inflow - meter calibration problems The current DO monitoring does not appear to be conducted in a manner that provides accurate results. OPERATION - Testing - Performance Monitoring The sludge accountability analysis indicates an excess of sludge produced beyond that indicated by the recorded wasting. This can indicate problems in performance monitoring. POTENTIAL "B" FACTORS: DESIGN - Secondary - Process Flexibility There is a lack of operational flexibility in the aeration basin( e. g., ability to utilize step feed or contact stabilization mode does not exist ). These options are not available with oxidation ditches. OPERATIONAL - Testing _ Process Control Testing This POTW is considered a small sized facility. Process control testing should be performed a minimum of 3 times/week. This requirement is currently being done daily but the operators are not doing the test needed for specific process control parameters. The lack of timeliness in performing the following process control test, or their absence altogether, causes improper operational control decisions to be made. Test - - Current frequency F/M - food to microorganism ratio -- test available but not performed Sludge residence time — test available but not performed Microscopic examination — test available but not performed 971968 9 Total system mass -- test available but not performed Sludge wasting volume — test available but not performed Mass control -- test available but not performed MCRT mean cell residence time — test available but not performed NOT RATED FACTORS: DESIGN - Plant Loading - Infiltration / Inflow The presence of excess infiltration or inflow may cause degraded process performance because the plant cannot handle the extra flow. NOTE: This factor may be symptomatic of underlying problems. Additional investigation may be necessary to determine other underlying factors prior to citation of Infiltration/Inflow as a factor limiting performance. (Typically, this factor is NOT cited, since it can be quite expensive to correct. The 592,000 gal/day average reported flow is at least 30% greater than 420,000 gal/day projected flow. This projection is based on a population of 4,200 assuming a 100 gallons per capita per day usage. This may be due to: - industrial contributions - infiltration/inflow or - meter calibration problems The installation of an intrachannel clarifier( boat clarifier ) in 1988 helped the hydraulic loading of the oxidation ditch during high flow periods. This device reduces the solids washing out of the final during the high flow periods. CHARTS and GRAPHS The following charts and graphs depict: - Influent Flows - Influent BOD and TSS - Effluent BOD and TSS - Calculated and recorded sludge production - Per capita flow to current influent flow 371.968 10 971968 t 971968 I� 971968 i s 971968 w N 971968 15 SUMMARY CCP for Berthoud WWTP The CPE conducted for the Berthoud WWTP indicated several performance - limiting factors. The primary factor was the aerobic digester design ( not enough volume to provide the minimum HDT of 15 days ), which the administration was already aware of and are in the process of addressing this problem. The other factors are associated with process control and laboratory testing for process control. The staff at the facility do some laboratory testing for the daily permit parameters, and need to do specific testing for solids management. A major concern of this evaluator was if an appropriate dissolved oxygen level is being maintained in the oxidation ditch and if the point of D.O. measurement for control represents the D.O. profile of the oxidation ditch. The blower for the aerobic digester runs only 50% of the time, this does not provide enough D.O. in the digester to allow the biomass to progress to the endogenous respiration phase, causing cellular breakdown and a reduction of solids which enhances water and solids separation. The main concern of the administration was the seasonal scum and foam build up on the oxidation ditch and the odor associated with it. The above performance - limiting factors would cause this type of problem. The records of the facility for the last 14 months indicated no permit violations, this indicates that the staff at this facility is doing a good job, they just need some process training to fine tune their skills. On the following page is the concern/action summary used to indicate the concerns and the actions needed to be accomplished, personnel assigned to the actions and the dates the actions are scheduled to begin. The facility and administration personnel assigned to these actions will be responsible for their completion at some time in the future and will be discussed and assigned at the exit meeting. 971968 lb DATE CONCERNS ( ACTION SUMMARY No. Concern Action Who Start Done 1 Sludge handling Aerobic digester - not enough capacity - build new digester 2 Oxygen probe Does not reflect accurate D.O. profile in oxidation ditch - move to a better location 3 Process control Mixed liquor volatile solids testing for solids management Run MLSS and MLVSS before wasting is done 4 Process control Microscopic examination of MLSS on a weekly basis and record microorganism pre - 'dominance 5 Process control Trending of key process control parameters - F/M ratio, MLSS, MLVSS, influent flow, calculated solids, wasted solids, microorganism predominance 6 Aerobicdigester Dissolved oxygen - run daily D. 0., record and trend 7 Aerobicdigester Oxygen requirements - run specific oxygen utilization test record and trend 8 Aerobicdigester Suspended solids - run spin, record and trend 9 Aerobicdigester Sludge retention time - calculate from waste added and solids withdrawal 971968 { APPENDIX D FLOOD PLAIN ANALYSIS REPORT LITTLE THOMPSON RIVER AT PROPOSED WWTP SITE (MWE, February 1997) 971968 p p p p F I R R I I FLOODPLAIN ANALYSIS REPORT LITTLE THOMPSON RIVER AT PROPOSED WWTP SITE Prepared for Town of Berthoud McLaughlin Water Engineers, Ltd. 2420 Alcott Street Denver, Colorado 80211 February 1997 92-008.003D 971968 INTRODUCTION This study was authorized by the Town of Berthoud in order to assess the 100 -year floodplain along the Little Thompson River in the vicinity of a proposed site for a new wastewater treatment facility for the Town. SITE DESCRIPTION The project site is located in Section 19, Township 4 North, Range 68 West in unincorporated Weld County, Colorado (Figure 1). The plant site is proposed to occupy approximately 10 acres of the Lewis property located in the southwest corner of Section 19. Upon favorable assessment of the site with regard to elevation, soils conditions and floodplain, the Town may proceed with acquisition of the property for the plant. I' L I FLOODPLAIN ANALYSIS The Corps of Engineers HEC-RAS computer model was used to calculate the 100 -year flood elevations along the Little Thompson River within Section 19, beginning at the bridge at 3 Road and extending upstream through the bridge at County Line Road and terminating at the bridge at 6C Road. The drawing in the pocket at the back of this report shows the topography surveyed on January 1997, existing roads, the proposed WWTP site, the Little Thompson River and the 100 -year floodplain. Eight cross sections were field surveyed and used to calculate floodplain elevations for the 100 -year flow of 7,200 cfs. Peak flow data was obtained from a June 1977 study of the Little Thompson River by the Corps of Engineers. Complete HEC-RAS files and other supporting data are contained in the Appendix. SUMMARY The hydraulic analysis shows that the 100 -year flow is largely confined to the immediate channel area. All bridges have adequate capacity for the 100 -year flow except the 6C Road bridge, where some road overtopping would occur. The resultant shallow overflow north of 6C Road would re-enter the channel upstream of the County Line Road bridge, as shown on the drawing. The analysis shows that the proposed wastewater treatment plant site is largely unaffected by the 100 -year floodplain, and it is recommended that the Town, proceed with acquisition of the site. Respectfully submitted, McLaughlin Water Engineers, Ltd. r)11 P John M. Pflaum, P.E. t.;,. Nr� • :y cD 14526 X. :: J ,OI L C'L t`, 92-008.003D:ANALRPr 971968 Project Title Subject 13er7'r+eva Wi9T'P .7 ti MAID McLaughlin Water Engineers, Ltd. a�Yu n Project No. 42 •00 P.Ct ?D Date fan I di Designed JM P Page 1 0 1 FFGUQE i [— l JJ,',./"N.. .1 / „ Mr• Y" i /- to _ ';;j" _. tea" • -f� t �ia\ 'ma . \fir / /, C. V 1 .f 7.11,r...-2.--- : :�.. j�� �i,... �� _ J -jam , "d 1 r -- r s6-� l - -- ,k; \� _ L,� 1 1,/ ICI N'TY_ MAP SCALE to 4eee l 971968 pia IIIIIDe COLORADO NAME: Town of Berthoud j REQUEST: DATE: September 2, 1997 Site application for capital improvements (digester, lift station, and force main/trunk sewer main) to the wastewater treatment plant. The improvements will be located at a new site, where eventually the entire treatment plant will be located. ENGINEER: McLaughlin Water Engineers, Ltd., Denver, Colorado LEGAL DESCRIPTION: SE 1/4, SW 1/4, Section 19, Township 4 North, Range 68 West. The site is located in the unincorporated part of Weld County. LOCATION: The new facility will be located south of Colorado Highway 56 and east of WCR 1. THE HEALTH DEPARTMENT STAFF RECOMMENDS THAT THIS REQUEST BE APPROVED FOR THE FOLLOWING REASONS: 1) The Town of Berthoud has had difficulty managing its sludge because the existing aerobic digester is undersized. 2) The North Front Range Water Quality Planning Association approved the plan on August 21, 1997. 3) The request complies with the Weld County Comprehensive Plan. The proposed use is listed as a Use by Right under Section 31.2.12 of the Weld County Zoning Ordinance tj\811 971968 Hello