Loading...
HomeMy WebLinkAbout02 - Design Report - Laurel Glen Ph 1 - Wastewater0 WASTEWATER SYSTEM DESIGN REPORT A. General u This report will give an overview of the proposed wastewater system for the Laurel Glen Development. The report includes a description of the proposed wastewater system and design parameters and an analysis of the effect on the existing wastewater facilities including downstream impacts and capacities. The development will be constructed in four phases but this report will look at the project in its entirety. Once the wastewater system is constmcted and approved, the system will become a part of the City ofBozeman system. The following references were used in the wastewater facilities design and capacity analysis: a. COB Design Standards and Specifications Guide, 2001 b. COB Modifications to Montana Public Works Standard Specifications (MPWSS) c. City Subdivision Regulations d. City adopted MPWSS and Adopted Addenda e. COB Wastewater Facility Plan, 1998 f. WQB Circular No. 2 g. City ofBozeman Zoning Map revision dated 10/11/2001 h. Sanitary Sewer Capacity Report For: Laurel Glen Subdivision, by Allied Engineering Services, Inc., December 2001 - updated January 2002. B. Proposed Wastewater Collection System The effluent generated by the development will flow into existing City of Bozeman sanitary sewer mains. The procedures and parameters outlined in the COB Design Standards and Specifications Guide, 2001 were used in the preliminary design of the sewer infrastmcture for the proposed development. The new sewer mains were sized to flow at no more than 50-percent of full capacity at peak hour conditions at full build-out of the subdivision. An average daily flow of 72-gallons per capita per day was used to determine flows generated by residential areas. Additionally, an infiltration rate of 150 gallons/acre/day was added to the design flow. The residential zoning densities and business and manufacturing flow rates are provided in Table 1 . The following infonnation summarizes the criteria used to size the sewer mains for Laurel Glen. BfflSiiBllltill •s ;'! •I-1- :^:; I;1:1 ^' ••'.•'.• '.• u.'.' i.! A peaking factor was calculated for each residential sub-area based on following formula: Qmax/Qave = (1 8 + P°'5) / (4 + P°5) (P = Population/thousands) 1 n n For the lots zoned B-l, a peaking factor of 3.4 was used based upon the overall peaking factor for the entire development (i.e. used total residential population in the peaking factor equation - see Appendix B). A summary of the peaking factors, peak flow, and preliminary size for each sewer segment is presented in Table 2. As shown in Table 2, the sewer main size for the development will be 8-inch with the exception of three 10-inch mns at north end of the project. The peak flow generated to size these mains is 384 gpm. Figure 1 shows the sewer main segments and their respective tributary sub-areas. A pipe slope of 0.5% for the east-west sewer segments and 1.0% for the north-south sewer segments was assumed for the preliminary sewer segment sizing. Detailed flow calculations are presented in Appendix B. Table 1 Residential zoning densities and business and manufacturing flow rates Zone Classification Population Zoning Density Density Flow (D.U./Acre) (people/acre) (gpd/acre) B-l M-1 M-2 R-l R-2 R-3 R-3A R-4 R-MH R-0 R-S :a495:;::i k20201 •% R. 1.5 '3. 4.8 f.8 4.8 •:;4.&':| 4.8 .1^ ^SSSSS^S^^S^S^ ^7.62. .12.19 12.19 12.19 12.19 12.19 .2.54 u 2 n 0 Table 2 Sewer segment peak How and sizing Sewer Downstream Segment # Segment # '.IS 9 !% Tributary Flow (gpm) Upstream Flow (gpm) Total Flow (gpm) Tributary Population Upstream Population Total Upstream Population Peaking Factor Peak Flow (gpm) Required Pipe Dia. (in) SliJ^' i31I .'Nil ::%|i% ri'SM ,«;,:; .X'. " :' 22:" :i'23. 24 :25?:: n -MJy :!, 27,5t 28 29 30 31-:;.::'- 32: :».-. 34 35 36 37 %, 39., 4Q:":^, 41 42 43 44 »; .45 46 n n n Table 2 (continued) Sewer segment peak flow and sizing BSffiSSSS%.^^^-.wwwfl-.^^.MM^ : ^.'yw. i ^ WSSSSK ^ tiSSiSt^ iimSS^: ;wyfr:'s::...«L w'iQ, !Stfcw:.i Ws%ISSfe «' ffis8i% R'Wv fi&M 3& m ': •X iWM siiffii m'KK tSSi. tt® J||[^:W "WS'S ;MS :;l2ii -,il|% Wf :'% ^yi.&.!^ AfgSA y S7' ;'^' ^;• i M1 ^•: I - •® :fi«l:-- ;a® ..:r:s3 ;:»64 IS,fiS;. %g:M. ~iw ;«, 's?:s.' i9iw ^.^i w^. T3 :^ :S9 K&%." TOTALS 0.0 0.0 0.5 n n r The lift station will be located on the downstream end of wastewater flow near Laurel Parkway and Oak Street. As noted by the City, the lift station will be located on a "common lot" owned by the property owner's association. The lift station will be composed of a wet well with two wastewater effluent pumps, a force main and an emergency backup power generator. The wet well will be a pre-cast concrete manhole. The effluent pumps will be mounted on rails for easy access during maintenance. The valveing will contain two valves for isolating the two wastewater effluent pumps and located above ground in a fiberglass reinforced plastic enclosure. The force main will carry wastewater effluent from the lift station to a City ofBozeman manhole located at the intersection ofDurston and Cottonwood. The emergency backup power will be either diesel or natural gas operated and will be housed in a weather proof enclosure. The control panel for the pumps will also be located in a weather proof enclosure. The footprint area of the lift station will comprise an area of approximately 20 feet by 20 feet. Access to the lift station components will be through a manhole access lid. The lift station will be owned and operated by the City of Bozeman. Maintenance costs will be paid by the homeowners and property owner's association through a surcharge on their sewer bill. C. Capacity Analysis (Downstream of Valley West Trunk Sewer) A capacity analysis was performed to determine the proposed development's sewer loading on existing downstream sewer lines. The report "Sanitary Sewer Capacity Report For: Laurel Glen Subdivision" dated December 2001 - updated January 2002 by Allied Engineering Services, Inc. analyzed the existing Valley West Trunk Sanitary Sewer to determine if there is capacity to add the wastewater flows generated by the proposed Laurel Glen Subdivision. Bob Murray, Project Engineer for the City ofBozeman, in his letter to Allied Engineering Services, Inc. dated January 9, 2002 indicated that based on the above report there is capacity for the development in the Valley West Trunk Sewer. The capacity analysis below analyzes the available capacity downstream of the Valley West Tmnk Sewer. Figure 2 shows a plan view of the portions of the existing sewer network that were evaluated in the analysis. The following parameters were used in the analysis: Average daily flow = 72 gallons/day/capita • Infiltration rate =150 gallons/day/acre Manning's n= 0.013 • Peaking factor = Q^ax/Qave = (18 + P°'5) / (4 + P°-5) (P = Population/thousands) Residential population densities and flow from areas zoned business and manufacturing were taken from Table 4.6.1-1 (page 51) of Wastewater Facility Plan by MSE-HKM Engineering, August 1998 and are summarized below in Table 3. u 5 0 Fi 0 Table 3 Residential population densities and flow from areas zoned business and manufacturing Zone Classification Population Zoning Density Density Flow (D.U./Acre) (people/acre) (gpd/acre) B-2 M-1 M-2 R-l R-2 R-3 R-3A R-4 R-MH R-0 R-S :13495'% K:;ao20:'l Eli2Q20.i --•s' •y*s»^"^, y %&ig i-6%lii -Al.ljll n.wm .til:i2.a-?|^ ty^m' ^.12.19.1: ),:2.54;: ^: u Summary sheets from the SANSYS computer sewer modeling program were obtained fi-om Bob Murray. Bob Murray also provided a list of subdivisions to add to the analysis as the SANSYS computer model is somewhat out of date. An Excel spreadsheet was set-up to analyze the effect on the existing collection system with the addition of peak sewer flow from the proposed Laurel Glen Subdivision in addition to peak flow from subdivisions not currently in the SANSYS model. Two flow scenarios were calculated: 1. Addition of - Laurel Glen Subdivision and existing subdivisions not modeled in current SANSYS model. 2.1+ future subdivisions (Hardest Creek Phases 5-11, and Annie Subdivision Phase III). Table 4 provides a summary of the peak flows added to the existing sewer system in the capacity analysis. Next, the peak flows from the various subdivisions were added to the existing sewer system at the locations shown on Figure 2. Manning's equation was then used to determine the available sewer capacity. Results of the hydraulic analysis, specifically the ratio of the calculated sewer flow to the full pipe flow for each segment of sewer main, are presented in Table 5. As shown in Table 5, the capacity of the existing sewer mains is exceeded at the following locations: 1. Manhole # 949 to manhole # 950 2. Manhole #95 5 to manhole #10102 Bob Murray, in a letter dated January 9, 2002, stated that approximately half of the Laurel Glen Subdivision could be built and served by the existing sewer collection system. The final plat for the remaining half of the development will be conditional upon installation of a relief sewer or 6 n r detailed flow monitoring to assure adequate capacity in existing mains. As described in the Wastewater Facility Plan by MSE-HKM, the relief sewer would consist of an overflow manhole installed to divert flows at manhole 946 (the intersection of Oak Street extended and Fowler Road extended) to the 21-inch line (line N2) in zone 7. This would require installation of approximately one half mile of21-inch sewer main between Oak Street and Baxter Lane. We plan to pursue flow monitoring. Table 4 Summary of peak flows for subdivisions Scenario Subdivision Population Peak Peak Zone Density Flow Area Peaking Flow w/infil. Flow w/infil. Upstream MH Clas. (people/acre) (gpd/acre) (acres) Population Factor (gpm) (cfs) to Add Flow 1 Laurel Glen B-l R-2 R-3 R-3A R-4 3495 7.62 12.19 12.19 12.19 9.16 34.74 32.51 37.67 21.84 265 396 459 266 83.3 52.6 76.8 89.0 51.6 0.19 0.12 0.17 0.20 0.11 Subtotal 1386 3.70 353.3 0.79 946 Valley West" Harvest Creek Phases 1-4 R-2 7.62 Harvest Creek Overflow Rose Park R-3 12.19 Castlebar Apartments R-3 12.19 Durston Meadows R-3 12.19 Lane Property" R-3 12.19 1751.1 3.90 59.20 451 4.00 96.3 0.21 1.38 9.64 118 4.22 25.8 0.06 6.75 82 4,27 18.2 0.04 30.42 371 4.04 78.0 0.17 161.29 1966 3.59 783.0 1.74 Total for Scenario #1 8.30 946 949 n 0 us MH# 946 947 948 949 950 951 952 953 954 955 956 957 10101 10102 10103 10104 10105 10106 10107 10108 10109 10110 10111 10001 10002 10004 10005 10006 10007 10008 10009 Table 5 Summary of capacity analysis DS MH# Grade Dia. (%) (in) Existing' 1 Peak (cfs) Contributing Total Peak Peak#l(cfs) Q#, (cfs) Q#i/Q^,, Contributing Total Peak Peak #2 (cfs) Q#, (cfs) Q^/Q^ii 947 948 949 950 951 952 953 954 955 956 957 958 10102 ,' <— r> (J I r- >- -—¥- 1 OAKBTBEET .....4 ! I CR0611BOW COURT SAXON WAY r _1 i BROAD SWOItD WAY 3 ———————4-— 8HBRW<X)D^yAY T~ OLBNEUBN DWVB I r ill s GLENBLLEN DRIVE ! S / ANNIE STREET r 1 ANNIE 8TRBET -1 ! !'" ! i— L..._....-._-. I'" !MMWn.;iH.,WA?' ; s I ) g ^ .J ! I GAD.DWvfi s -V r- GUIIWOCID 'i"DB.T'-IVE l T GLENWOOD DRIVE =J=JiL^ ! r-— BR001SBIDE;UU<S SHADOW GIEN DRIVE j__. DURSTON ROAD (COUNTY) f / LEGEND SEWER MAIN SEWER MANHOLE •s.^: k ^ I Ji IK NO. f!EVISION5 DRAWN BY DATE 0 300 600 900 SCALE: 1 INCH - 300 FEET PROJECT ENGINEER: SRS DESIGNED BY; WMS DRAW BY; WMS REVIEVCD BY: SRS, CGB LAUREL GLEN SUBDIVISION PROPOSED SEWER LAYOUT BOZEMAN, MONTANA r BAXTER VALLEY WEST TRUNK SEWER OAK •RRGPOSEO •tSABREL • GffiN: -isugBils*l "^•- I I DURSTON! I I ! I LOCATION MAP r 4000' ( 10010 10009 10008 10006 10( 10004 10007 10002 10001 10111 10110 10109 10108 10107 » •( BAXTER 9S6 (J0101) PROPOSED LAUREL GLEN SUBDIVISION HARVEST CREEK FLOW FLOW FROM: LAUREL GLEN SUBDIVISION- AND VALLEY WEST 955 (J0205) V 954 (J0204) 953 (J0203) 952 (J0202) 951 (J0201) OAK FUTURE I I til 5 °' ° g g ° s i s 0 ) 7T r\ S 56 S57 S58 m ^. 3.13 acres ?! p ,SZ6 2.^% 1.7^,4 IK J' 2.40 acre 2.0 acres res ocr / |S75| ;i S5 54 S3 S2 SZ7 <i"~- \ 1'70 °c''" 0.46SZ9 2.01 acres |ijy 0.46 ocr ,3l"c8. iZ26 a es 2.16 acres 0.58acre8 SZ10 i,,4~oc'r.SZ12 a o^^^li es 4.86sZ3 ., -S74 |S73| acres SZ16 4,35 ocr s SZ27 SZ11 2.45 acres SZ73 S! SZ3Q 2.64 acres 0.78 acres 0.68" acres o.olZ14 acres '"~~T ..•'/ S72 S68 [7 SZ13 1..57 ac acres s . .SZ18 ..SZ75 ^ 1,63 acres 0.46 acres 1.08 acres 0,86 acrea S19 S1B -c'^--^^. (.00 SZ32 ocras s SZ3t 1.26 acres SZ35 ; 2.79 acres ST? 8 s \ w S71 SZ74 SZ21 SZ13 1.17 acres 0.95 acres 0.95 acres 'a K -S233 € 0.59 acres .SZ25 6.18 acres SZ36 ! 0.51 acres 2 ^ s 0.84 acres —SZ23 SZ20 M SZ34 SZ24 1.71 acres 4.07 acres 0.68 acres o,72-ocrcs V. r- s% SA1 S40 S64 s V} 7, 269 SZ43 || EI!l/?E^ (fjj AUG 2s 2032 ^BuTFBI:^^^ ENGINEERING SERVICES. INC. August 27, 2002 Bob Mun-ay, PE Project Engineer City ofBozeman P.O. Box 1230 Bozeman,MT 59771-1230 RE: Laurel Glen Design Report Review Comment Responses J.O. 00-185 Dear Bob: Attached please find our responses to your review comments for the Laurel Glen Design Report. Please review the submitted material at your earliest convenience. If you have any questions or need additional infonnation regarding this project please feel free to contact us at 582-0221. Sincerely, Allied Engineering Services, Inc. ^ Chris G. Budeski, PE Senior Civil Engineer enc: Laurel Glen Design Report review comments responses ec: Chuck Hinesley, Owner file ^ S:\ProjectsV2000\00-185 Laurel Glen Sub\Design Report\Bob Murray Letter 08-27-02.doc 32 Discovery Drive • Bozeman, MT 59718 • (406)582-0221 • Fax(406)582-5770 1 ] 1 ] 2. Provide a node diagram. See enclosed Figure 2. 3. Provide the results of a run for max day plus fire flow for each node. Note that the minimum allowed fire flow per the Fire Department is 1500 gpm. The results of the max day plus fire flow run for each node are included in Appendix D. The minimum allowed fire flow for residential areas with buildings less than 3600 square feet is 1000 gpm as stated in the 1994 Uniform Fire Code and verified with the City of Bozeman Fire Department. A minimum allowed fire flow of 1500 gpm was used throughout the rest of the development for any building over 3600 square feet. 4. The text states that all mains other than the main in Durston will be 8 ". The main in Oak needs to be 12" to match what is being installed to the east. The water main size in Oak Street has been upsized to a 12" ductile iron main. This information has been updated in the water model, and all flows still meet the City of Bozeman standards. Sanitary Sewer: 5. The text states the lift station will be installed on a "common lot". Recent plans have shown otherwise. This issue is being resolved through planning. Although the preliminary plat shows this lot as private, it will be dedicated to the City of Bozeman during the platting of phase II of the project. Until the next phase of the project is platted, the lift station will be located within an easement to the City ofBozeman. 6. The lift station must be enclosed in a building rather than a separate enclosure as described. The proposed lift station will be enclosed with a building. 7. The lift station and mains to/from Durston to the lift station must be sized to convey flows from a reasonable service area south of Durston. Additionally, a main should be extended into Durston to ser^e the area. Allied Engineering has met with Greg Stratton with Morrison Maierle to detennine the area and zoning in the Valley West development that will flow into the Laurel Glen lift station. A main will be extended to the south side of Durston at Westgate Avenue for future extension by the Valley West development. Main sizes and lift station pumps will be sized accordingly for the additional flows. Page 2 of 6 ?6B__ \—y67 acres 1.ocres08 acres 2.04 0.95 acres s SZ70 3.03 acres SZ71 1.37 acres s sl SZ61 .....J-^-—-.t- 5.47 acres 1 S266 S43 S44 S45 3.2?^ res 4.46 SZ37 acres s .24 acre 'es 1.70 acres (n SZ77 SZ76 SZ65 0.49 a cr<s >n 1.21 ocr 1.29 acres SZ80 1.10 acres w K es '59 •s 1.84 acres S39 SZ64 0.25 acres s SZ47 j 1.2^ 1.17 acres ZB1 SZ62 s- co acres 0.70 acres s 6JZ41 ¥K 2 acres ^ 536 S.35 0.67'acrea .1 S.34 33l I. S55 S 54 S53 I I" I iZ^'9 0.79 acres SZ60 ; ^ \0.43 acres: .sz63 1.89 acres SZAS 0.66 acres m V) SZ46 R 0.92 acres s _SZ58 ^ s. 2.07 ocr .SZ56 0.52 acres S-ZS3 0.9.5 acrss SZ50 -SZ55 0.75 acres 1.33 acres SZ39 SZ78 0.96 acres 1.20 acres SZ38 1.71 acres ^11 ss^ Ml '52 I S49 532 li S.S1 ^ SZ57 acres \ 1.48 acres _SZ54 i __SZ53 0.54 acres ' 0.86 acres .SZ51 0.9.3 acres SZ49 1.40 acres SZ40 -SZ56 0.98 acres 0.81 ocr s!.S'.:::^«vi'StS3^»^l ! LEGEND SSS9!!' KR? SZ,|1 s» SEWER ZONE IN S-1 DESIGNATION SEWER ZONE IN R-2 DESIGNATION SEWER ZONE IN R-3 DESIGNATION SEWER ZONE IN R-3A DESIGNATION SEWER ZONE IN R-4 DESIGNATION SEWER ZONE BOUNDARY PROPOSED SEWER MAIN PROPOSED SEWER SERVICE PROPOSED SEWER MANHOLE SEWER ZONE NUMBER SEWER SEGMENT NUMBER }1 II i| sl u NO. REVISIONS DRAWN BY _DATE_ 4?0 SCALE: 1 INCH - 300 FEET PROJECT mGtNEER: CGB DESIGNED BY: PJS DRAWN BY: DLO REVIEWED BY: CG8 LAUREL GLEN SUBDIVISION SEWER ZONE MAP BOZEMAN, MT w^/ yw^ ALLIED ENGINEERING SERVICES, INO. Civil Engineering Land Surveying Geotechnical Engineering Structural Engineering K DISCOVERY DRIVE BOZEMAN.MT 59718 PHONE (406) 582-0221 FAX (406) 582-5770 PROJECTJt 00-185 DATE: FEBRUARY 20021 SEWER ZONE MAP FIGURE 1 OVERALL SHEET 1 OF 1 LAUREL GLEN SUBDIVISION SEWER ZONE MAP s s s i •LANE PROPERTY FLOW FLOW FROM: CASTLEBAR. ROSE PARK. DURSTON MEADOWS AND ANNIE PHASE III s s ? s ^ 9 f 99 S LEGEND 0 EXISTING SEWER MAIN EXISTING SEWER MANHOLE NOTE: 1. ONLY THOSE PORTIONS OF THE EXISTING CITf OF BOZEMAN SEWER SYSTEM USED IN THE CAPACITr' ANALYSIS ARE SHOWN ON THIS FIGURE. CITY OF BOZEMAN EXISTING SEWER MAP 1" = 1000' I is I I/) NO. REVISIONS DRAWN BY DATE SCALE AS NOTED PROJECT ENGINEER: CGB DESIGNED BY: PJS DRAWN BY: DLG REVIEWED BY: SRS, CGB /C£W LAUREL GLEN SUBDIVISION CITY OF BOZEMAN EXISTING SEWER BOZEMAN, MT ^SKS/ -^'^KS,-, ALLIED ENGINEERING Civil Engineering Land Surveying Geotechnical Engineering Structural Engineering 32 DISCOVERY DRIVE BOZEMAN.MT 59718 PHONE (406) 582-0221 FAX (406) 582-5770 PROJECT #: 00-185 DATE: JANUARY 2002 SEWER ZONE AREAS FIGURE 2 OVERALL SHEET 1 OF 1_| LAUREL GLEN SUBDIVISION. SEWER ZONE AREAS_ ss..-g I -:^^ ALLIED ENGINEERING ;RVICES, INC. Civil Engineering Land Surveying Geotechnical Engineering Structural Engineering 32 DISCOVERY DRIVE BOZEMAN.MT 59718 PHONE (40«) 382-0221 FAX (40«)582-5770 PROJECT (fc 00-18S DATE: 2/2002 U-OVERAU FIGURE 3 OVERALL SHEET 1 OF 1 _LAURELGLEN- UTILITY LATOUT" 10103 10104 10105 10106 10107 10108 10109 10110 10111 10001 10002 10004 10005 10006 10007 10008 10009 10010 0.20% 20 0.20% 20 0.20% 20 0.20% 20 1.00% 20 1.00% 20 0.80% 20 1.34% 20 0.80% 20 0.20% 20 0.10% 24 0.10% 24 0.10% 24 0.24% 24 0.24% 24 0.24% 24 0.21% 24 0.95% 24 0.95% 24 0.95% 24 0.95% 24 0.95% 24 1.06% 24 1.06% 24 1.06% 24 4.30% 24 1.06% 24 0.56% 24 0.89% 24 0.98% 24 0.97% 24 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 0.88 6.76 6.76 6.76 6.76 6.76 6.76 6.76 6.76 6.76 6.76 6.76 6.76 6.76 6.76 Total 4.69 1.59 0.27 1.74 5.57 5.57 5.57 7.16 7.44 7.44 9.18 9.18 9.18 9.18 9.18 9.18 9.18 9.18 9.18 9.18 9.18 15.06 15.06 15.06 15.06 15.06 15.06 15.06 15.06 15.06 15.06 15.06 15.06 15.06 15.06 0.90 0.90 0.90 1.15 0.53 0.53 0.74 0.57 0.74 1.48 1.28 1.28 1.28 0.83 0.83 0.83 0.89 0.68 0.68 0.68 0.68 0.68 0.65 0.65 0.65 0.32 0.65 0.89 0.71 0.67 0.68 0.27 0.10 5.57 5.57 5.57 7.44 7.80 7.80 9.55 9.55 9.55 9.55 9.55 9.55 9.55 9.55 9.55 9.55 9.55 15.43 15.43 15.43 15.43 15.43 15.43 15.43 15.43 15.43 15.43 15.43 15.43 15.43 15.43 0.90 0.90 0.90 1.20 0.56 0.56 0.77 0.59 0.77 1.53 1.33 1.33 1.33 0.86 0.86 0.86 0.92 0.70 0.70 0.70 0.70 0.70 0.66 0.66 0.66 0.33 0.66 0.91 0.72 0.69 0.69 8.30 0.37 From City ofBozeman SANSYS output dated May 20, 1999, obtained from Bob Murray D. Conclusion Based on this analysis, the proposed wastewater system for the Laurel Glen Development provides adequate ser/ice to meet the flows generated from the proposed development. This project will require the approval of the City Engineer and MDEQ. c 8 949 950 950 950 952 2 Harvest Creek Phases 5-11 Annie Phase 3 R-2 R-3 7.62 12.19 76.06 580 3.94 122.1 0.27 1635 199 4.15 43.1 0.10 Total for Scenario #2 0.37 949 950 3 from "Sanitary Sewer Capacity Report For: Laurel Glen Subdivision", December 2001 - updated January 2002, by Allied Engineering sewer main from MH J0410 to J0411 was blocked off & flow direction was changed to the north to tie into MH 949 (J0310) c reserved sewer capacity of 307, 200 gpd per XL Limited Partnership Annexation Agreement 0 7 0.5 1.3 1.0 1.3 0,5 1.2 3.5 0.0 0.0 1.7 1.5 1.7 0.7 0.4 1.2 3.2 0.0 1.2 0.0 2.0 0.4 0.9 1.9 0.9 1.2 2.2 0.0 103.4 6.3 3.3 0.5 0.0 1.0 0.0 0.0 1.2 0.0 21.3 21.3 21.3 19.6 15.8 11.9 6.9 5.6 4.4 1.2 1.2 0.0 2.4 0.4 0.0 0.0 0.0 1.2 0.0 0.0 103.4 6.3 3.3 0.9 0.5 2.3 1.0 1.3 1.7 1.2 24.8 21.3 21.3 21.3 17.3 13.6 7.7 6.0 5.6 4.4 1.2 1.2 2.4 2.4 0.4 0.9 1.9 2.2 1.2 2.2 103.4 0.0 0.0 7.5 7.3 22.0 16.2 20.0 8.0 20.5 59.2 0.0 0.0 29.3 26.3 29.9 12.2 7.2 20.8 54.4 0.0 20.8 0.0 34.0 6.2 15.4 32.2 16.2 20.7 38.2 0.0 1344.9 101.5 53.0 7.3 0.0 16.2 0.0 0.0 20.5 0.0 363.7 363.7 363.7 334.5 270.0 203.2 118.6 96.1 75.2 20.8 20.8 0.0 40.2 6.2 0.0 0.0 0.0 20.7 0.0 0.0 1344.9 101.5 53.0 14.8 7.3 38.2 16.2 20.0 28.6 20.5 423.0 363.7 363.7 363.7 296.3 233.1 130.8 103.2 96.1 75.2 20.8 20.8 40.2 40.2 6.2 15.4 32.2 36.9 20.7 38.2 1344.9 4.24 4.31 4.40 4.43 4.34 4.39 4.38 4.36 4.38 4.01 4.04 4.04 4.04 4.08 4.12 4.21 4.24 4.25 4.28 4.38 4.38 4.33 4.33 4.43 4.39 4.35 4.34 4.38 4.34 3.71 27 14 4 2 10 4 6 7 5 99 86 86 86 71 56 32 26 24 19 5 5 10 10 2 4 8 9 5 10 8 8 8 8 8 8 8 8 8 8 s 8 8 8 8 8 8 8 s 8 8 8 8 8 8 8 8 8 8 PVC pipe meeting COB specifications will be used for all the sewer mains. Since all sewer main segments will be 10-inch diameter and smaller, a maximum manhole spacing of 400 feet was used and a manhole barrel size of 48-inches is required, except for inside drop manholes which will be 60-inches in diameter. Manholes will be constmcted according to COB specifications. All sewer services will be 4-inch or 6-inch PVC installed at 2 to 4% grade. Sewer services will connect into the main with in-line gasketed wyes. A 4-inch sewer service with a grade of 2% can convey approximately 60 gpm at 50% capacity. Our flow calculations show that no individual lot generates over 60 gpm of peak flow. A plan view of the proposed sewer infrastructure is shown in Figure 3. Sewer mains were placed along the centerline of the street on tangential alignments. On curvilinear street alignments, sewer mains were kept a minimum of five feet from the edge of the concrete gutter for collector and arterial streets and 3.5 feet for local streets. On curvilinear street alignments we attempted to keep manholes in the center of the street. However, to keep the required separation distance between water mains and the edge of the concrete gutter in addition to maintaining an 11-foot separation water and sewer mains, some sewer manholes do not fall on the street centerline. Laurel Glen subdivision will utilize a lift station for pumping wastewater effluent into the City of Bozeman collection system. The downstream manhole in Laurel Glen is approximately 15 feet lower than the tie in manhole for the City of Bozeman, thus preventing gravity flow into the collection system. The City of Bozeman engineering department has noted the need for a lift station in the pre-application plan review. 4 SBIBEI:!? WS^Sli!K5 iffi 16, w m' VS re 21 22 23 13 :25: -:26; s: :'27 !28 29 29 3.1 28 28 34 35 36 :3T. ;'27; ^ ; 48, w 42 43 44 •S.&. 0.0 1.3 1.7 0.0 1.7 1.7 1.5 1.2 1.3 3.8 1.1 16.1 0.3 1.3 1.5 0.8 0.6 0.0 0.0 2.9 1.3 0.9 0.8 4.8 0.0 8.3 0.2 0.1 0.0 0.7 1.7 1.5 1.2 1.7 0.5 1.6 1.5 1.0 0.8 0.0 1.0 0.0 1.2 0.8 1.6 0.4 78.6 77.3 75.6 7.4 3.3 1.5 0.0 ].3 0.0 64.4 63.3 35.2 34.8 1.5 0.0 0.6 0.0 10.7 2.9 0.0 6.5 5.5 4.8 0.0 32.0 12.5 12.3 11.4 3.9 0.0 1.5 0.0 0.0 4.6 4.1 2.4 1.0 0.0 0.0 11.2 0.0 10.2 9.0 8.2 0.0 6.3 78.6 78.6 77.3 7.4 4.9 3.3 1.5 2.5 1.3 68.2 64.4 51.3 35.2 2.8 1.5 1.4 0.6 10.7 2.9 2.9 7.8 6.5 5.5 4.8 32.0 20.8 12.5 11.5 3.9 0.7 3.2 1.5 1.2 6.2 4.6 4.1 2.4 1.0 0.8 11.2 1.0 10.2 10.2 9.0 1.6 6.7 0.0 21.7 28.6 0.0 27.9 28.9 25.8 19.9 22.0 64.2 19.1 7.2 5.5 20.9 25.2 13.2 10.5 0.0 0.0 49.6 21.5 15.4 13.2 81.4 0.0 10.4 3.7 1.9 0.0 11.3 27.8 26.1 20.3 28.1 8.5 27.7 25.2 16.6 13.4 0.0 15.5 0.0 18.3 13.0 24.4 6,3 921.9 900.2 871.6 124.5 54.7 25.8 0.0 22,0 0.0 682.8 663,7 451.6 446.2 25.2 0.0 10.5 0.0 181.1 49.6 0.0 110.0 94.6 81.4 0.0 400.1 210.6 206.9 191.6 65.1 0.0 26.1 0.0 0.0 78.0 69.5 41.8 16.6 0.0 0.0 179.0 0.0 163.5 145.2 132.2 0.0 101.5 921.9 921.9 900.2 124.5 82.6 54.7 25.8 41.9 22.0 747.0 682.8 458.9 451.6 46.1 25.2 23.6 10.5 181.1 49.6 49.6 131.5 110.0 94.6 81.4 400.1 221.1 210.6 193.5 65.1 11.3 53.9 26.1 20.3 106.2 78.0 69.5 41.8 16.6 13.4 179.0 15.5 163.5 163.5 145.2 24.4 107.9 3.82 3.S2 3.83 4.22 4.27 4.31 4.36 4.33 4.37 3.88 3.90 3.99 4.00 4.32 4.37 4.37 4.41 4.16 4.32 4.32 4.21 4.23 4.25 4.27 4.02 4.13 4.14 4.15 4.29 4.41 4.31 4.36 4.38 4.24 4.27 4.28 4.33 4.39 4.40 4.17 4.39 4.18 4.18 4.20 4.37 4.23 300 300 296 31 21 14 7 11 6 265 251 205 141 12 7 6 3 44 13 13 33 27 24 20 129 86 52 48 17 3 14 7 5 26 20 17 11 4 3 47 4 43 43 38 7 28 10 10 10 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 s 8 u 3