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1. Sewer ModelingPUBLIC 201 ISt venue East PO Box 1997 Kalispell, MT 59903 Phone: 406-758-7720 Fax: 406-758-7831 www.kalispell.com /public works MEMORANDUM To: Doug Russell, City Manager Dj?- From: Susie Turner, P.E. Public Works Director/City Engineew Date: 1/22/2014 Re: Trunk Line A Sewer Alternatives Work Session Presentation The workshop presentation is a continuation of the workshop from October 281h of last year. Since the last presentation, Public Works developed and evaluated a few short-term alternatives to the West Side Interceptor. Part of the evaluation included additional sanitary sewer modeling. The presentation will provide a short review of the previous presentation, an overview of the developed alternatives, the results of the modeling, and staff recommendations for the current sewer allocation issues. Enclosed handouts to Council include: • Bullet discussion summary points — Outlining discussion topics to be detailed further at the Work Session 1 / 22/ 2014 TRUNK LLNE A SA111ITARY SEWER C. PA [TY GFTIG REVIEW Single Family Household A* 1 ERU = Equivalent OF xAc� Residential Unit 4� 'j°Fr` i e '; 1 / 22/ 2014 ERU EXAMPLE Hotel with 100 Rooms 0.25 ERU per Room 25 ERUs MUNICIPAL FACILITIES EXCLUSION (MFE� • Signed by City as part of a new development plan approval. • Required before development in the City can start construction. • Tells Montana Department of Environmental Quality (MDEQ) that City staff has reviewed design and the design appears to be in compliance with City and State standards. • Also Tells MDEQ the City has adequate capacity for the supply of water and disposal of sanitary sewer. • Protects the interests and investments of new development by reserving water and sewer capacities for approved developments. • Although MDEQ approvals typically expire in 3 years, a municipality's allocation does not expire. • Under current City Policy, an MFE allocation would only be revoked if a Preliminary Plat expires. P� 1 / 22/ 2014 DEVELOPMENT NORTH SILVER-1, BaoaxMFE ALLOCATIONS :� STILLWATER in d WEST VIEW ESTATES OLD O GLACIER TOWN SPRING CENTER GLACIER RAIRIL EYE C NIC HUTTON RANCH STARLING ��� . FVCC s.�a�se GRANDVIEW LIFTSTATION Silverbrook - Phase 1 253 West View Estates 93 Hutton Ranch 5 Spring Prairie 20 North Allocation 3 1 / 22/ 2014 DEVELOPMENT �9) FOX TROTTER 0 ,. 74IERIDIAN. ■' APTS. "CENKrrCHEN T-RAEi'.qL—I .J SPRIIV REE SP£N eRIDGE CREEK WILLOW CREEK Lr MFE ALLOCATIONS Mountain Vista 29 Spring Creek 105 Aspen Creek 69 Diamond Ridge 19 Northland 67 Lone Pine 13 Westwood 22 Empire Estates 3 Blue Heron 3 32 South Allocation Available Growth = 10 ERUs 411h Alley West and 5th Street West 18" Vitrified Clay Pipe Remaining Capacity Calculation Design Capacity = 2,302 ERUs Current Flow = -1,390 ERUs Development North = -556 ERUs -332 ERUs New Allocations = -14 ERUs Available Growth = 10 ERUs 11I 1 / 22/ 2014 THE PROBLEMi CONTI NUED b 10 ERU 1 F� L7 r THE PROBLEMi CONTINUED A °BE180 ERU Q Di`K '61 1 / 22/ 2014 THE OPPORTUNITY TRUNK LINE E 24" Q TRUNK LINEA 10,810 ERU THE L O� —TFER-MSOLUTI ON West Side Intercor Phas f- e , Bottleneck - 180 ERU r� West Side Interceptor _ Phase 2 t ` llyy West Side Interceptor Phase 1 ,, I, -,r rX 1 / 22/ 2014 THE _ H-- M- T-TERM CRSTA CLF R 'n ` N 9 _ � 8 7 6 5 DESI GN TI ME MONEY The Short-term Alternatives C rA 1 / 22/ 2014 The Short-term Alternatives Mile Drive Lift Stations w 250 gpm a VANDERBILT DP5 � � w z u7 220gpm------- TH� ° ALTERNATIVE 1 544 gpm The Short-term Alternatives Synchronize Lift Stations $20,000 o ° z - � 250 gpm Fp 73� 1- 2 a VANDERBILT u� 220 gpm � ALTERNATIVE 1 ��` I 544 gpm 1 / 22/ 2014 The Short-term Alternatives Lib rty St. a � C R t D � 3 � z j 1 2 Mite Dr. Y 1 The Short-term Alternatives Lib rty t. fl� o -o 3 - � 2 Mite Dr. �� pF R fl � X 1 / 22/ 2014 The Short-term Alternatives 10" IAlternative2 12"Lib` 15" Alternative 3� Will Require MDEQ Deviation Require more than normal maintenance $270, Will Require Easement from County 000 2 Mite Dr.. $180,000 18" � ] Trunk Line E I `R n events in 1 / 22/ 2014 WHAT MAKES THE MOST SENSE? ALTERNATIVE 1 - Lift Station Synchronization • Quickest Alternative to Put in Action • Cheapest Alternative ($20,000) • No Throw -Away Cost • Costs $138 per ERU Gained (145 ERUs Gained) • At 2% growth rate, it could buy us about 9 months ALTERNATIVES 2 Et 3 - Splitter Manholes • Should be done together for best results • Will be unnecessary when West Side Interceptor is complete (Throw Away Cost - $270,000) • Costs $1,400 per ERU Gained (193 ERUs Gained) • At 2% growth rate, they could buy us about 1 year. ALTERNATIVES 1, 2 Et 3 • 338 ERUs Gained • $290,000 • Combined value of $858/ERU gained • At 2% growth rate, could buy us 1.7 `K 1 / 22/ 2014 FUNDING 1 -Alternative 1 - Lift Station Synchronization • Project funding split between impact fees and rates • By limiting the pipe flow to the largest pumping rate, there is a potential of 46.3% reduction in flow in the 3 Mile Drive force main. This reduction in flow allows capacity for development. Therefore, this project could be 46.3% funded by impact fees or $9,260. • 53.7% or $10,740 of the project would have to come out of rates. This was not a budgeted item. The rates portion of this project would have to come from other line items in the sewer fund. Potentially, remaining funds in the utility relocation for MDTs Hwy 93 Bypass at 3 Mile Drive. 2 - Alternatives 2 and 3 - Splitter Manhole • Project would only serve growth so it could be paid completely by impact fees. Sewer Impact Fee Funds Available • $1,652,240 at end of FY 13/14 • $250,000 in line item for main / lift station upsize a AtC`-C f STAFF RECOMMENDATIONS 1 - Proceed with Alternative 1 • Alternative 1 provides the best value. 2 - Commit to the West Side Interceptor • Send out a Request for Proposals to qualified engineering firms for the design of the West Side Interceptor. • Seek a temporary deviation from the MFE process to allow for new development. • The City would have to present our case to the DEQ Deviation Committee in Helena. • The Committee will vote on what we present. • The City would need to provide specifics about how we would design, fund, and construct the WSI. 3 - Wait on Alternatives 2 and 3 • Use the $270,000 that would be consumed by these two alternatives and apply it towards the long term solution - the West Side Interceptor. 13 1 / 22/ 2014 STAFF SEEK NG DI RECTI CN 1 -Alternative 1 • With direction from council, Public Works will move forward with the purchase and installation of synchronization system for the 3 lift stations on the 3 Mile Drive force main. 2 - Request for Proposals (RFPs) • With direction from Council, Public Works will send out RFPs to qualified engineering firms for planning and design of the West Side Interceptor. 3 - Other Direction(s) • Other direction by Council? `C!