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HomeMy WebLinkAboutFOSSIL LAKE PUD SECOND - Filed GC-GENERAL CORRESPONDENCE - 2003-11-28ua Engineering, Inc. 4803 Innovation Drive Fort Collins, Colorado 80525 Office: 970.229.9668 FAX: 970.226.3855 July 23, 1999 TO: Jim Birdsall Everitt Companies 3030 South College Ft. Collins, CO 80525 FROM: Amy L. Johnson, E.I.T. Richard L. Aust, P.E. CC: Project File RE: Fossil Lake Development Irrigation Pump System Ft. Collins, Colorado RAW WATER IRRIGATION PUMP SYSTEMS APPROACH RECOMMENDATIONS Conceptual Plan MEMORANDUM MEMORANDUM k is desirable to irrigate the proposed Fossil Lake Development open spaces with a raw water source. This memo describes the proposed approach. The Fossil Lake Development is located on the southeast corner of County Road 9 and County Road 36, north of the Fossil Lake Reservoir as shown in Figure 1. The total site is anticipated to have approximately 38 acres of common space with irrigated turf at the completion of all phases. The proposed pumping system will be sized to serve a total of 38 irrigated acres in a 10 hour irrigation window. rJ� cd� The raw water wi!I be diverted from the New Mercer ditch into the "upper pond". Ev _ a JA Companies' civil engineers are designing the diversion infrastructure. An 18-inc' ADS avity pipeline (also designed by the civil engineers) will carry water from the uppe.- pond to the "lower 5 pond' when the upper pond is full and still receiving vrter from the ditch. O /e.rflows for each ponD a-_ being des:,ined by the civil engineer Th crsap: fe- :'n-. Irrigation purnp system involveS tyre use of water from co:n t:na uoperand owa- C '_ Tra I'ri-ation p'-Imp system tha`. V/Ill se^ie tfle Irrigation sysr&-- io open spaces MEMORANDUM: Fossil Lake Development Irrigation Pump Systems July 23, 1999 Page 3 will be located at the upper pond. A transfer pump will be located at the lower pond to pump water to the upper pond in the event that the upper pond is not full from the ditch water. Probable Annual Water and Pumping Requirements An analysis of the turf water requirements was completed based on the assumptions previously stated. This analysis is shown in Table 1. A pump system rated for approximately 630 GPM at 220 ft total dynamic: head will be required to irrigate the 38 acre site within a 10 hour water window. The irrigation system at Fossil Lake is assumed to be designed for a pressure of 75 PSI at the connection point to the pump system. Friction loss in the new PVC mainline is expected to be considered in the 75 psi design pressure. The elevation throughout the site varies approximately 25 ft. Based on the future irrigation system assumptions, the total pressure used for the preliminary pump design was 90 PSI (208 feet) downstream of the pump building. Raw Water Delivery Infrastructure and Routing The desired method of supplying raw water to the irrigation system includes the diversion of raw water from the New Mercer ditch into the upper pond (as designed by the civil engineers) and the pumping of raw water from the lower pond to the upper nd. Raw water will gravity drain from the upper pond to the lower pond through an 18-inc DS pipe (as designed by the civil engineers). In the event that raw water is not available to the upper pond from the New Mercer ditch, water will be pumped from the lower pond to the upper pond to assure irrigation water to the common spaces. A transfer pump station will be located in a 60-inch wet well adjacent to the lower pond. The pump station will consist of two single phase, 5 HP submersible effluent pumps rated for 163 GPM at 57 ft of head each. The pumps will each be installed on a slide -rail system for maintenance and access. Each pump will have a 2-inch discharge pipe penetrating through the wet well wall. The pumps will be a Fairbanks Morse Pump or equal. Outside of the wet well, underground, the pipes will be connected and increased to a 6-inch pipe. The 6-inch C:1200 PVC gas'keted pipe will be routed from the transfer pumps to the upper pond to transfer the water in the approximate rouse sho`rm in Figure 1 and coordinated with the civil dra;rines. The minim_irn cover dept'n is 36-inches over the pipe. Approximately 3400 ft of pipe v:il', be re]_lire-, based on the proppSed pip= roiti g fro.-^ the cis/I. eng;.'.= The pump is nr=: - enis o-)e da/s iaa io- ;`;ate- c;e, a peri t 20 ho,, - - of canal, PLC W ce opa:e7 aq;aoen: Co the :`le[ ,,/e� ab^,= gro._' i An e:7cic_z_ a 5_,.' as a =:.'�; l`_7S0x ; Ills be _ _ n _ TABLE 1 PEAK SEASON DESIGN AND ANNUAL WATER REQUIREMENTS Aqua Engineering Inc. 4803 Innovation Drive Fort Collins, Colorado 80525 July 23, 1999 Prepared by: ALJ EVER:FOSIL PLANT MATERIAL A PLANT MATERIAL B AREA, acres 38 0 PEAK SEASON DESIGN IRRIGATION REQUIREMENT, inches/day 0.25 P1 0.00 OPERATING LOSS, inches "' 0.0E 0.00 TOTAL DAILY APPLICATION REQUIREMENT, inches 0.31 0.00 TOTAL DAILY APPLICATION REQUIREMENT, acre'ft 0.98 0.00 TOTAL DAILY APPLICATION REQUIREMENT, gallons 319,300 0 SEASONAL IRRIGATION REQUIREMENTS, inches 36 0 SEASONAL EFFECTIVE PRECIPITATION, inches "' 7.0 7.0 TOTAL SEASONAL IRRIGATION APPLICATION, inches 29.0 -7.0 TOTAL SEASONAL IRRIGATION APPLICATION, acre'', 91.8 0.0 TOTAL SEASONAL IRRIGATION APPLICATION, gallons 29,923,000 0 IRRIGATION FLOW REQUIREMENT WITH AN IRRIGATION WINDOW OF 6 HOURS, (gpm) 1,043 0 IRRIGATION FLOW REQUIREMENT WITH AN IRRIGATION WINDOW OF 8 HOURS, (gpm) 783 0 IRRIGATION FLOW REQUIREMENT WITH AN IRRIGATION VVINDOLV OF 10 HOURS, (gpm) 625 0 NOTES PPD?OSED IRRiG,.TION SYSTEM OPEP.,ATIQNA.'_ E7FICIENCY IS ASSUMED TO EE SCi: FJ?OSFD IRRIGATION SYSTEM TAP UTl_IZATID>: EFFICIEN >..' IS ASSUMED TO BE F_j',': T tiz UTI _IZATIO'J EFFICIENCY IS DEFINED AS T He AVERAGE DnSIG'; FLOVV ,WERAG= AVAILABLE FLO,'. SEASO`-I RRIGAT!OL: 0:= = N!D;=,Y IS ASS'J,`V=D FOR P' r-, 7:.!�,TERIAL A <?J IS B,',SED ON NATION.`J_ 4'IEA.THEP. SERViC- Dr,TA AND A CROP COEFFICIENT O- 0.80 PE SEASON IRRIGATION REQUIREMMENT OF C.G- I,V'D..-,Y IS ASSU,`d=D FOR PLANT t,'ATERIAL E A.P!D IS BASED ON NATIO�'LAL WEATHER SERVICE DATA AND A CROP COEFRICIEN T OF 0-0. 5) A SEASONAL PRECIPITATION OF 14-INCHES IS USED AND IS EASED ON NATIONAL �; i-ATHEP, SERVICE INFORMATION. PRECIPITATION IS ASSUMED TO BE 503'3 EFFECTIVE 0 V123`PROJECTSVNatr.123 MEMORANDUM: Fossil Lake Development Irrigation Pump Systems July 23, 1999 Page 5 Controlling the transfer pump station based on the water level at the upper pond requires communication between the water level sensor at the upper pond and the transfer pump controls at the lower pond. It was not desirable to install 3400 ft of communication wire with the transfer pipe because of potential maintenance concerns with that length of wire. The unobstructed line -of -site distance between ponds is about 2600 ft. Therefore, a radio control system was investigated for operating the transfer pump based on the water level in the upper pond. Water level probes located in the irrigation pump station wet well at the upper pond will be adjusted to allow a 6-inch water level drop before signaling the transfer pump to start. A PLC (programmable logic controller) and a spread spectrum radio will be located at each pump station. The spread spectrum radios do not require a license. When the water level drops 6-inches from the normal operating elevation, the PLC at the upper pond will send a radio signal to the lower pond PLC to start the transfer pump statioin. After the transfer pumps have supplied enough water to raise the water level back to the normal operating elevation, the water level control probe at the upper pond will communicate with the PLC and send a radio signal to the lower pond PLC to stop the transfer pump. The proposed radio and PLC equipment recommended by AmWest Control, Inc. includes a World Wireless 900 SS Direct Sequence Spread Spectrum Transceiver and a Network 3000 Model RTU 3305 intelligent remote terminal unit. AmWest Control, Inc. would also provide the BIW Controls water level control probes, and programming of the PLC. The irrigation pump station at the upper pond will consist of an intake structure from the pond (intake screen, pipe, line gate valve), and an automatic skid mounted pump system. The pump system includes two 25 HP variable frequency drive, vertical turbine pumps, an automatic backwashing filter system, a control panel, pressure transducer, and flow sensor. The irrigation Pump station will be rated for 630 GPM 24 a pressure of 90 psi downstream of 211 pump station components including the filter. The pump station will be a PSI Flosvtronex, SyncroFlo, Watertronics, or other equal pre -fabricated, pump station. An 8-inch CL200 PVC stub -out from the pump station will be available to connect to the irrigation systems of the common areas. The pump s'-id will be about 12' by 6, requiring a b,iilding approximately 18 by 12. The bu'rJding will also include a heater, ventilation fa- vents, lighting. elect-ical panels, and outlets he brig 3:���� pump sta tl0❑ 4`/i!I be hgused I^ a f:"P. ":,e p'.!m bLlliding deslg -e `I t�'13 0,'/nef 5 C,] c'. et'. __ ei....... V/e' aT;. �, 'cDUlre 2 MEMORANDUM: fossil Lake Development Irrigation Pump Systems July 23, 1999 Page 6 Electrical Service It is understood that only single phase power is available at the lower pond and both single phase and three phase, 460 V electrical service is located at the upper pond. The preliminary load calculation for all components in the irrigation pump station building is 98 HP (about 73 kVV). 'The preliminary load for the transfer pump station is 10 HP (about 7.5 kW. Possible Alternatives If three phase, 460 volt power can be provided at the transfer pump station, the pump selection will increase and the cost may decrease significantly. Lli rr H i FMITTED TO EXCELLENCE MEMO'FO: Matt Lafferty, Latimer County Planning FROM: Traci Downs I / DATE: April 18, 2001 SUBJECT: Fossil Lake PUD, Second Filing ENGINEERING DEPARTMENT Post Office Box 1190 Fort Collins, Colorado 80522-1190 (970)498-5700 FAX (970) 498-7986 Based on our meeting held with Everitt Companies, Northern Engineering and the representatives from the City of Fort Collins on April t0 2001, it is my understanding that the complex issues and concerns associated with the Second Filing have been addressed. Our department finds the submitted information to be acceptable at this time, however, we realize that the City of Fort Collins still has some outstanding issues with the proposal that they would like addressed prior to our Final approval. One of these issues is regarding the proposed handicap ramps at the intersections. The proposed ramps shown on the plans are non -directional ramps, which were permissible under the previous Urban Area Road Standards. The City is now requesting directional ramps, which are required under the newly adopted Latimer County Urban Area Street Standards. The Fossil Lake PUD Second Filing Final Plat was submitted pursuant to the previous Urban Area Road Standards, therefore, we will not require the applicant to provide the directional ramps with this proposal. We do not foresee a need to have another formal review of this proposal. We are expecting that the remaining issues, which were also discussed in the meeting, will be adequately addressed and presented to the appropriate City representatives for review. Prior to our Final approval, we ask that a letter be submitted from the City to our office that confirms that they have had a chance to review the changes. If you have any questions please call me at498-5701. cc: Jim Birdsall, Everitt Companies George Schock, Northern Engineering Dave Stringer, City of Fort Collins Engineering Department, 281 N. College Ave, Fort Collins file. hd&,,r ,AplunchkVdnl, lHf d lake 2nd filing -doe