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HomeMy WebLinkAboutMONTAVA - PHASE D CORE AND IRRIGATION POND - BDR240006 - SUBMITTAL DOCUMENTS - ROUND 2 - Other Water/Sanitation Districts (2)■ `� � , � �\ � � ,1�.,,�a , ��� � �' � ;�:; :'� , •� ,,: �.'`t'a . .,.. .; = � �"' � c, �Y ��� , :.� i � � ��.� . t7 1 � �� For Sanitary Sewer Analysis Results Montava Phase D TST ,>,< ,,�,.,,�� ��� � v: r,:� � �! 1}+ x'' w"• z �i`r 1 _ .. �M�^ t I �I Pi _ _r r i I `��.rF �., .�. �l..r.,��4,1� , N ■ Montava Phase D 1.0 Introduction 1.1 Scope and Purpose Sanitary Sewer Analysis This report presents the results of the Sanitary Sewer Analysis for the Montava Phase D Subdivision in Fort Collins, Colorado. This sanitary plan was prepared to identify infrastructure needs as the area develops. Montava Phase D is surrounded by future Montava Subdivision Phases, so the sanitary lines built with Phase D will be utilized to service the current and future phases. Certain assumptions were made concerning the development of the future surrounding properties. Updates to this Master Plan will be needed as plans for the future development of the area are finalized and changes to the overall concept necessitate an update. 1.2 Project Location and Description The proposed Montava Phase D Subdivision site is located west of N Giddings Rd between Richards Lake Rd and Mountain Vista Dr in Fort Collins, Colorado and consists of approximately 52 acres of undeveloped land. The proposed development contains 329 Single Family lots, Tracts intended for future multi-family development, and open space. N � VICINITY MAP NOT TO SCALE TST. INC. CONSULTING ENGINEERS Page 1 Montava Phase D 1.3 Existing Conditions Sanitary Sewer Ana�ysis The existing infrastructure around the Montava Subdivision includes a 21" Boxelder Sanitation District trunk line that runs through the middle of the proposed Montava Phase D site. This 21" trunk line carries effluent flow southeast through the Montava Subdivision. The layout of this existing trunk line can be seen in Appendix A. 2.0 Design Criteria and Assumptions 2.1 Sanitary Design Criteria and Assumptions The Boxelder Sanitation Districts Standards in combination with the Fort Collins Utilities Water and Wastewater Design Criteria Manual, adopted on May 2, 2017 was used to design the alignment, elevations, and sizing of internal sewer systems for Phase D. The future Montava Phases were based on the Montava Development Yield Estimate for Water System Analysis which can be seen in Appendix B. This yield estimate was used to determine the number of dwelling units as well as the square footage of commercial/employment buildings for each phase. Sanitary Design Criteria • Average Daily Residential Demand = 75 gal/capita/day • Average People per Dwelling Unit = 3 capita/DU • School Site = 1,020 gal/day/ac • Commercial Demand = 200 gal/day/1000 sq ft -0.16 • Peaking Factor = 2.6 x Q average daily, cfs • Infiltration & Inflow = 0.347 gpm/ac • The minimum and maximum velocity at the design flow rate shall be two (2) fps and ten (10) fps respectively • Manning's Equation Friction Factor ("n") = 0.010 3.0 Proposed Sanitary Layout 3.1 Proposed Conditions The proposed sanitary consists of 15", 12", and 8" main lines that outfall into the existing 21" Boxelder sanitary trunk line. Two connections to this existing mainline are proposed and the extents of each sanitary "basin" along with the proposed sanitary sewer layout of Phase D and approximate locations of future sanitary lines can be seen in the exhibit located in Appendix C. The sewer sizing and layout has been determined based on demand calculations and analysis that is discussed in section 4.0 of this report. TST. INC. CONSULTING ENGINEERS Page 2 Montava Phase D 4.0 Sanitary Sewer Analysis and Results 4.1 Sanitary Sewer Demand Calculations Sanitary Sewer Ana�ysis The previously mentioned criteria and assumptions were used to calculate the average day residential and non-residential sanitary flows from each lot, tract, and future phase. The average day effluent flow was applied to its associated upstream manhole and the cumulative base flow was determined through each stretch of pipe. A peaking factor was determined from each cumulative base flow value. Infiltration and inflows were determined based on the cumulative area flowing to each manhole. The peak eff1uent flow through each pipe was then determined by multiplying the cumulative base flow by the peaking factor and adding the cumulative infiltration and inflow. The peak effluent flow was converted from gallons per minute (gpm) to cubic feet per second (cfs). The peak flow was then input into FlowMaster (10.03.00.03) where the Manning Formula was utilized to determine velocities and flow depths within each pipe during peak events. All calculations were done in an Excel spreadsheet and the velocities and % Full (d/D) values were taken from FlowMaster and summarized within the Excel spreadsheet provided in Appendix D. 4.2 Sanitary Sewer Analysis and Results Based on the result, the peak flow scenario indicated no modeled pipes exceeded a d/D capacity of 80%. Four pipes slightly exceeded 50% d/D using the peak flow scenario. The total peak effluent discharge was also calculated and determined to be adequately handled by the existing 21" trunk line. 5.0 Conclusions and Recommendations The Montava Phase D sanitary sewer has been designed to meet the Boxelder Sanitation District Design Criteria and to adequately service the proposed and future Montava Subdivision. If there are any questions or additional information needed, please do not hesitate to contact us. 6.0 Appendices Appendix A - Existing Conditions Appendix B - Density Assumptions Appendix C- Proposed Sanitary Layout Appendix D- Sanitary Sewer Analysis Results TST. INC. CONSULTING ENGINEERS Page 3 ,`o��'� s�ni , lo� ��"� � �o 9F � m �) Production Date: 2/20/2018 Facilities O WWTP � Lift Station - E1 Points Pipe labels are length, diameter, & type Pipe Diameter Pressure Mains 6, 8, 10 in CDOT Force Main � 12, 15, 16, 18 in �� Timnath Force Main �21, 24 in Walker Mfg. Force Main ��27, 30, 42 in �� E1 Force Main Jetter Sensitive �� Harmony Ridge FM Preliminary Pipe Larimer Parcel � <all other values> O DRI B AEI O PRO `�� BSD MH By Sub-basin � DRI/PRI � BSI O RAPS � CIS (� OCI O CDOT � TMG � BXI • PDI O PLT • WMPS • CSI <Title> � 0 700 1,400 Feet �Farnsworth GROUP Montava Yield Estimate By Phase May 26, 2021 �---------- . -------------*------� � i' ' ' � r � � � J ' FARM `�` i � PHASE A � � �� 1 � � I i 1 1 i I I : PHASE B � `� _ .` �,' � � �" --t �. . �`j i PHASE M X♦ . � i � � i � ' PHASE C i `-' r' i � i � � 1 _J.� \ l � ` PHASE L �� PHASE D ._ _ � � `� � �� � � � � ��' � i � � i � i � i i i i '�� PHASE E � ' pHASE F � PHASE K ���; ---- �. i � Ji � i � _. � ` � ii �.� �� � � i i '�i. -"- i � PHASE G � 'r - '`• ' ``� i i � �� t�' PHASE J � i o �`` PHASE H � i pHASE I � i i � n � i � `------------�---1—" ---}'�----'----------r'-------------' Estimated Units By Type and Phase i�*�r,� � s ���I� — : "�_ y � �•� �II�' � f .,:�•�.�— ' I . F� `- ,_______r______ " __'+ i � i i � i i � i i � i � � i PHASE N i PHASE 0 �� i i i i i i i i i i i i i i `_'_"__ I 1 Unit Type Phase Total ID Name A B C D E F G H I J K L M N O # % SF % MF 50 du 29 du 31 tlu 18 tlu 41 du 169 du 6°/ ........................................................................................................................................................................................................................ ................................. ]6tlu 58tlu ]Odu 17du 43tlu 62tlu 23du 55du 30tlu 434du 17°ro ............. . .__.__.__. . . _.__.__._ . ._._._._._.__._. _._._._._._._._._. ._._._._._._._._._ _._._._._._._._._. . ._._._._.__._._. ._._._._._._._._._ . _.__._._._._._. _._._._. ._._._._. . . . ._._.__.__.___ sstlu 58du 40tlu 65du 24tlu 42tlu 26tlu 51tlu 64du 48tlu 484du 19% 39°�oMF ............._____________________________________________________________________________________________________-________________- ]6 du �0 du 49 du 81 du 52 du 3] du 60 du 50 du 89 du 48 du 612 du 23°ro .......... ....________________.__.__._-______________._-._-____'_____________________"______"'___._-._______________________ '__.__.__.__.________ 60 du 4� du 102 du 204 du �1 tlu 56 du 31 tlu 90 du 68 du 89 du 32 du 6fi du 916 tlu 35% ..............""""'"""'"""'"""'"""'"""'"""'"'"'"'"'"'"'"'"'"""'"""'"""'"""'"""'"""'"'"'"'"'"'"'"""'"""'"""'"""'"""'"""'"""'"""'""""""'"""'"""'"""'"""'"""'"""'"""'"'"'"'"'"""'"""'"""'"""'"""'"""'"""'""""""'"""'_"' '"'"'"'"'"'"'"'"'"'"""'"""'"""'""""""'"""'"""'"" 0 tlu 0"0 ........................................................................................................................................................................................................................ ................ ................ 36 tlu 18 du 126 tlu 240 tlu 198 tlu 162 du 270 du 306 tlu 54 tlu 72 tlu 36 du 1,518 tlu 90°io _._._.__ ____________ ____________ _____________ ___.___.___. __.___.___._ __.___.___.__ ___.___.___. __.___.___._ __.___.___.__ .__.___.___.___.__ 61%SF ___.___.____ Odu 0% ]S du ]5 du 25 du 175 tlu 10°e 268 du 311 du 154 du 444 du 560 du 321 du 340 du 376 du 421 du 301 du 303 du 281 du 228 du 4,308 du 41.8 i ac 45.06 ac 16 42 ac 51.60 ac 35.6] ac 20,64 ac 38.34 ac 16.17 ac 28.89 ac 33.88 ac 39.76 ac 50.69 ac 23.66 ac 30.00 ac 45.30 ac 517,95 ac ........................................................................................................................................................................................................................ ................................................. � du/ac 7 tlulac 10 tlWac 9 tlu/ac i6 tlulac 16 tlu/ac 9 tlu/ac 24 tlu/ac 15 tlulec 9 du/ac B tlu/ac 6 tlulac 10 tlWac ._.__ ____________ ____________ _____________ ___.___.___. __.___.___._ __.___.___.__ ___.___.___. __.___.___._ __.___.___.__ .__.___.___. _.___._ ___.___.____ 11 tlu/ac 12 dulac 16 tlu/ac 15 du/ac 2'1 dulac 26 du/ac 15 du/ac 39 dulac 25 dulac 15 tlu/ac 13 tlu/ac 10 dulac 1� tlu/ac PUD calculation methotl ........ .................. .................. .................. .................. M'n mum per PUD Est mated per PUD Estimated Non-residential By Phase Unit Type Phase Total Name A B C D E F G H I J K L M N O Area 39,]87 sl 43,980 si 21,02] sf 104,794 sf �������� �����3.600s7 ��������� 11.0525f����� ��������� 10.995sf 21,02]s� ��������� ��������� 11.1605f ��������� ������ 57,834sf ������ ........................................................................................................................................................................................................................ ................................................. 29,4]2 s� 29,320 sf 224288 sf 210,000 sf650.000 sf 1,743,080 sf 3,600 sf 80,311 st 80,295 sf 266,342 sf 11,160 sf 210,000 sf650,000 s 1,305,]08 sf Phase N and O Concept Layout i _ _ � � � � � ► � i i , , , , 0 � ','ii 0 I�, � � C �_ Y- i � �' - - l� 1 � �� �; ,p � . o ' 0 '� I `���� ' „� � y. �I,���, `�' Q�� - ',. � � I � ��J� -� 0 � � I� �' - � -��� �A � � �I n ` � i =-,�--�; i'4� _ _ �.Y 0 I _ ; 0 i _=1 � . '� 0 � �, , _ , , , � � m 0 � �� Overall Program Distribution Program Distribution Program Size Notes a1.87 ac 45.06 ac .................................................. 16R2 ac .................................................. 51.60 ac _.._._ 3567ac _ .___. 20.64 ac 38.34 ac Phase calcula[ions are approximate, ..................._.._____.._............. however they are reflected in ihe 16.17 ac PUD. Phase boundaries are 28.89 ac 9enerally drawn down road centeriines or greenway corridors. 33.88 ac .._.._.._.._.._.._.._.._.._..___.._.. 39.76 ac 50.69 ac .................................................. 23.66 ac .................................................. 30.00 ac .._.._.._.._.._.______________. 45.30 ac .._.._.._.__ ............................................................................................ 76.00 ac ............................................................................................................. 108.00 ac Per agreement ._.._.._..___________________.._.._.._.._.._.._.._.._.._.._.._.._.._.._.. 87.00 ac Agreement is between 80 and 100 189 00 ac Approximate ............................................................................................................. 45.00 aC ApproXimaie � ST _ ��� ��� ��� ��� ��� �� �� � LI�TitI.l�14. l �m�����������