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Home My WebLink About20061361.tiff Page 1 of 1 Esther Gesick From: Brad Mueller Sent: Thursday, May 04, 2006 9:45 AM To: Esther Gesick Subject: USR-1540 Church Barn conditions Esther-- Staff has reviewed the six conditions of approval for USR-1540 required prior to scheduling with the Board and finds that all have been met. Additional conditions will be met prior to recordation of the USR plan. Thank you, Brad 14. EXHIBIT 2006-1361 I G1Sf° �S�D 5/4/2006 P.O.Box 7676 Tetra ' '•:. Phone:970-663 7480 Loveland,Colorado 80537-0676 1 ogics Fax:970-667-9959 Consulting, LLc January 26, 2006 Casseday Creative Designs, LLC Attn: Robb Casseday 55 South Elm Avenue, Suite 210 Eaton, Colorado 80615 RE: Onsite Wastewater System(OWS) Concept Report Church Barn, LLC Lot B of AMRE 3961 Eaton, Weld County, Colorado Job No. 06-1081 Mr. Casseday, As requested, we have prepared this concept report regarding the feasibility of permitting and construction of onsite wastewater systems (OWS) for the proposed church facility. We understand the Weld County Planning Department is requiring this information to assess the feasibility of this project where OWS are required to provide sewer service. The site is located approximately 2 miles southwest of Eaton and the northwest corner of County Roads 33 and 70. The 13.9± acre property has an existing 3-bedroom residence, metal barn and sheds. Slopes are generally gradual, sloping to the south. The church is proposed for the southeast corner of the parcel as presented on Figure 1. We understand the desire is to have a total maximum of 387 church patrons and dinner events may be planned for 160 patrons. It had not been determined if the church events and dinner events could occur on the same day. Appendix 30-A of the Individual Sewage Disposal Regulations for Weld County provides estimated average wastewater flows for churches without kitchen at 5 gallons per person per day (g/p/d), or 1935 gallons per day (gpd) total for 387 people. For dinner patrons, kitchen use, the average wastewater flows are estimated to be 10 g/p/d, or 1600 gpd for 160 people. If church and dinner days occur simultaneously, the combined average flow for that day would be 3535 gpd. Preliminary percolation results were prepared by Terracon, under Job No. 21065001. Subsurface conditions described by Terracon were 6 inches of topsoil overlying sandy lean clay to a maximum depth explored of 8 feet. Six percolation holes ranged in percolation rates ranging from 29 minutes per inch (mpi) to 60 mpi and an average of 45 mpi. Conventional drain field OWS are 4. EXHIBIT e-mail:terralogics@att.net L.-- OWS Concept Report • Job No.06-1081 Page 2 suitable for these conditions. Locations of the percolation test were not available when this report was prepared. A septic permit for the residence at the north end of the property indicates an average percolation rate of 8.4 mpi. Percolation rates may vary throughout the property. When there are average wastewater flows on any peak day of 2000 gpd for a single system, a Site Application procedure at the State level will be required. Other stipulations for multiple systems on a single property are discuss in Policy 6 of the Water Quality Control Division of the Colorado Department of Public Health and Environment. This process is normally very expensive and time consuming and we understand the owner desires to avoid this process. We have therefore prepared two concepts that may avoid this procedure. Concept 1 — Wastewater flow on any single day would be limited to 1935 gpd, or 387 church patrons. Either there would be no kitchen use or kitchen facilities would be very limited so that the total combined average flows would be 1935 gpd, or less. Kitchen use would be limited to light sink image (e.g. no major dishwashing, no garbage grinding). The OWS could be slightly oversized to allow 64-gpd additional flows for light kitchen use. Wastewater flows for the dinner events could be as high as 1930 gpd, or 193 people, on non-church days. Special event dinners would need to occur on days other than those for the church sessions to avoid the combined flow limit. Our preliminary calculations suggest one OWS with two drain fields with gravel-less chambers of 2400 square feet each may be appropriate. A concept layout for these conditions is presented on Figure 1. Concept 7 -In the event church sessions and dinner events are planned on the same day, two separate OWS can be constructed that can increase the total average peak flow for those days. If the new church building is constructed separately from the proposed future church expansion, separate OWS could be constructed provided the well-to-drain field setbacks do not overlap. However, to avoid overlapping setback envelopes, the wastewater flows will need to be reduced to 268 people for the church and 134 people for the dinner events. These numbers may be adjusted by increasing church patrons and reducing dinner patrons for final design as long as well setbacks do not overlap and average wastewater flows on any peak day are less than 2000 gpd. In any event, total average wastewater flows allowed for any single property is less than 6000 gpd. Our preliminary calculations suggest two separate OWS of approximately 3280 square feet each may be appropriate. A concept layout for these conditions is presented on Figure 2. Monitoring water usage with water meters should be considered to estimate actual flows after construction. Measurements of inside-use only water should be kept so that actual wastewater flows can be estimated on peak-use days, along with the number of persons during peak days and how the facility is used. In the event actual measured flows are less than those estimated for the design, it may be possible to permit an increase of the capacities of the facility. The OWS designs are required to be approved by a Registered Professional Engineer in the State of Colorado. Other items to be considered for the OWS design are buffering peak flows by means of dosing, large septic tank capacity and site-specific percolation tests. Single peak flows may need to be spread somewhat evenly over low-use periods. This can be accomplished by dosing the effluent to the drain fields with a pump controlled with a timer. The pump also acts as a lift station and gravity flow from the tanks to the drain fields is not at issue. The exact locations of the percolation tests were not available when this report was prepared. Proposed drain field locations may • OWS Concept Report Job No.06-1081 Page 3 not be located at the percolation test area. The County may require additional percolation tests if drain fields are proposed in areas other than those previously tested. There is a substantial difference in percolation rates reported for the existing residence to the north and those described by Terracon. Therefore, it may also be an advantage to the owner to conduct additional tests to determine if better percolation rates can be found. In conclusion, OWS appear to be feasible for providing sewer service for the church facility. However, type of use and number of people the facility will serve will be limited by average wastewater flows on peak days being kept less than 2000 gpd for single OWS and by well-to-drain field setbacks for multiple OWS on a single property. Two concepts for OWS are presented in this report. The OWS will need to be designed with engineer review. Additional percolation tests may be required. A program to monitor water usage after construction is recommended to provide more accurate estimates of wastewater flow. It may be possible to amend usage of the facility if acceptable water image evidence can be provided. This report is intended to provide concepts and invite comments from the parties involved in the planning stage of your project. If you have any questions concerning the information provided in this report, please contact our office. Sincerely, Terra Logics Consulting, LLC _,,s�\�1.%% v%%%%.%%%%%%%%%%%%%%%% .‘t may. ••,��p\GATE%. 1 P o :�4�Q tti�Jts et-A. 0�i Thomas W. Finley, C.P.G. i'F°MgS W FAN oo�-PR 7 copies sent CHURCH BARN, LLC LOT B OF AMRE 3961 PART OF SECTION 10 Scale T 6 N., R 66 W OF THE 6TH PM 1° = 150' —, WELD COUNTY, COLORADO 150' orth Existing Drain f li Field - Location to be determined } 100-foot # - I well-to-drain field setback I Metal Barn 253-foot . Po well-to-drain field setbac \i I B ilding and Property Lt e Setbac r / f1 H �' 13.9± a acres c iU ) ? . eept .� " , ). ' a l l l l l rf 1 1 1 1 ill Dram" <Fields ' " z- • I � � � ' • IIIIIIIIII IIIIIIIIIIII IIIIIIIIIIII _ ; .j1tIVUYihluulllululuJullulu Weld County Road 70 Concept I -Peak average wastewater flow on any single day to be 1935 gallons per day,or 387 church patrons and no kitchen use. Kitchen use for dinner events,limited to 160 people,would need to occur on days other than regular church days. Concept sketch adapted from drawing,Project No.05-09-126,prepared by Casseday Creative Designs,LLC. PO BOX'ere CONCEPT 1 ,,\ L ND.COWHADO ONSITE WASTEWATER SYSTEM JOB NO. 06-1081 C9' 66S-481) FIGURE 1 CHURCH BARN, LLC LOT B OF AMRE 3961 PART OF SECTION 10 Scale T 6 N., R 66 W OF THE 6TH PM '" = 150' WELD COUNTY, COLORADO 150' orth Existing Drain _ I li Field - Location to be determined F. 100-foot f� well-to-drain field -� setback Metal Barn Concept: t Drain/Feld, [ (Kitchen/ginner) r� " �` �`' ''•'��' / t i Biuth and"Property I co 1 an6Setbacks 13.9± cC acres 181-foot j well-to-drain field ` setbacks t W � • 9TIIIIiiIlltI Drain F ielil " { (Church) / Weld County Road 70 1 t Concept 2-Peak average wastewater flows may occur simultaneously for church patrons and dinner patrons.Church patrons to be limited to 268 people.Dinner patrons to be limited to 134 people. Peak average wastewater flow for church on any single day to be 1341 gallons per day and no kitchen use.Peak average wastewater flow for dinner and kitchen on any single day to be 1341 gallons per day. Facility to be divided into two separate buildings. . Concept sketch adapted from drawing,Project No.05-09-126,prepared by Casseday Creative Designs,LLC. PD BOX-9>fi CONCEPT 2 TtL „� VFIAND.COLORADO ONSITE WASTEWATER SYSTEM JOB NO. 06-1081 C-phi 910.80.4.#&1 FIGURE 2 Page 1 of 1 Brad Mueller From: Linda Hulse [Linda@cassedaycreativedesigns.com] Sent: Monday, February 13, 2006 3:07 PM To: Brad Mueller Subject: Church Barn Attachments: Weld County Planning -letter 2.doc Brad, I just wanted to touch base with you on Church Barn. You said we needed to discuss the conditions of approval before County Commissioners. I thought I would let you know where we are at and then you can let me know what else you need. A. Storm water drainage— I have submitted the Preliminary Drainage Report. B. Traffic Study— Don waived the traffic study when we changed the access point to WCR 33 instead of 70. He asked instead that we provide him with a letter from the Pastor describing the congregation. I have given that letter to him and have attached a copy to this email. 1-.c*s + f rol g C. CDOT- I did not see any concerns from CDOT so I'm not quite sure what your looking for. D. Landscape -We are meeting with the landscaper who did the landscape for the riding arena on Wednesday to get a plan for the Church. ✓ E. Lighting — Parking lot lights were included on the plan. If you need more detail or other lighting let me know. F. Sign -The sign was noted on the plat just north of the entrance. If that needs more detail let me know. Give me a call when you have a chance. We are anxious to get to County Commissioners. Best Regards, Linda Hulse Project Manager Casseday Creative Designs, LLC 55 South Elm Avenue, Suite 210 Eaton, CO 80615 (970)454-8740 (970)454-8742 fax (970) 381-6022 mobile robb©cassedaycreativedesigns.com www.cassedaycreativedesigns.com CONFIDENTIALITY NOTICE: This e-mail is intended solely for the person or entity to which it is addressed and may contain confidential and/or privileged information. Any review,dissemination,copying,printing or other use of this e-mail by persons or entities other than the addressee is prohibited. If you have received this e-mail in error,please contact the sender immediately and delete the material from your computer. EXHIBIT asetsite 02/13/2006 MAR-06-2006 MON 10:08 AM WELD COUNTY PUBLIC WORKS FAX NO. 970 304 6497 P. 01/01 Atle,kir MEMORANDUM Ire TO: Don Carroll DATE: 22-February-2006 Ili p O FROM: Brian Varrella,P.E.,Public Works Department COLORADO SUBJECT: AMRE-3961,Church Barn (u 5t 4- I sclo 0-to..,n:44.4. Drainage Comments 4 Offsite drainage issues have been neglected but must be addressed for this submittal. Existing 10-ft contours on the drainage drawing sheet indicate runoff enters the site from the north and east. o Existing contours should be shown at 2-ft vertical intervals, and should be extended far enough offsite to determine the extent of the drainage area affecting the study site. o Offsite flows must be accommodated on this site for the 100-year undeveloped condition. ci The applicant must show how water arrives to the proposed detention pond at final. Flow directions have not been indicated on the parking lot, and it is not clear how flow arrives to the detention pond from adjacent landscaped areas. Please discuss in the report and indicate on the drawing sheet. 4 Please show calculations for outlet structure sizing for the detention pond, and discuss in the report at final. O Please provide an emergency overflow section for the pond at final for flows exceeding the 100-year storm. O The detention volume seems low compared to the FAA Method detention spreadsheets from UD&FCD. Please double-check detention volume calculations for this submittal. 4. EXHIBIT L ' B Post-Ir Fax Note 7671 Dale lass / To f IA—k A b i�'k From al.-u.AI Co./Dept n Co. __ Page l of 1'i. 14 nlN !/J � Phone U \ Phone 4 Fax P Fax II ri t a PUBLIC WORKS DEPARTMENT 1111 H STREET Weld County Planning Department p.O. BOX 758 IGREELEY OFFICE GREELEY, COLORADO 80632 WIDc MAR 3 1 2006 WEBSITE: :(970)-304co.us PHONE: (970)-304-6496 COLORADO RECEIVED FAX: (970)-304-6497 LETTER OF TRANSMITTAL Date: 31 March 2006 To: Brad Mueller,Planning Department Subject: Church Barn (AMRE-3961) drainage report Enclosed Please Find: 1-Drainage comments memorandum 1 —checklist of review items 1 —drainage report and drawings, with comments Submitted to you: ❑ For your review and approval ❑ Approved as submitted ❑ For your use ❑ Approved, subject to notes ❑ As requested • Returned for corrections ❑ For your signature/signatures ❑ For your information Remarks: Please contact us if you have any questions. Signed: t Brian K. Varrella, P. E. 4. EXHIBIT u.` tt0 MEMORANDUM W� ' TO: Brad Mueller, Planning Department DATE: 30-March-2006 �• FROM: Brian K. Varrell Public Works Department COLORADO SUBJECT: AMRE-3961, Church Barn Weld County Public Works Department has reviewed this Amended Recorded Exemption request. Comments made during this phase of the subdivision process may not be all-inclusive, as other concerns or issues may arise during the remaining application process. Drainage Comments ❑ Public Works received a drainage report for the Church Barn (AMRE-3961) on March 24, 2006. The report was prepared by Michael Walker, P.E., and is dated March 24, 2006. ❑ The final submitted drainage report was must be stamped, signed, and dated by a registered P.E. ❑ Weld County will not maintain drainage related areas. This must be addressed by the homeowner's association or owner. Drainage Comments: ❑ Redline comments have been provided in the Preliminary Drainage Report dated March 24, 2006. ❑ The information provided in the drainage report does not sufficiently address drainage issues, and the drainage report cannot be approved at this time. Public Works requests the applicant address all comments and re-submit the drainage report for further review and comment. The following items are of top concern: o The applicant must show all proposed contours and existing offsite contours on all plan sheets submitted with the drainage report. Onsite and offsite drainage basin delineations cannot be verified by Public Works until this information is provided. o Drainage connections between proposed conveyance and storage features must be clarified, and flow paths defined in detail and all plan sheets. o Hydrologic design methods presented in Chapter 10, Section 3.2.1 of the UD&FCD Manual are not accepted in Weld County. The 100-year developed condition storm flows shall be intercepted and detained onsite and released at a rate not to exceed the 5-year historic rate, as per Weld County CODE 24- 7-130(D.2). The applicant shall:address the comments listed above art to specifie;step*tithe review process stated. The review process will continue only when all appropriate elementsliavcbeen submf .Any issues of concern must be resolved:ttith the Public Works Departmertt prior totordingSfinal plats. Page 1 of 1 WELD COUNTY DRAINAGE REPORT CHECKLIST Name: Church Barn Plan Date: March 24,2006 from Drexel,Barrel)&Co. ..r Location: NW Corner of WCR 70 and WCR 33 Rev.Date: March 31,2006 Case#: AMRE-3961 Rev.By: Brian K.Varrella,Public Work Comment Headings I Adequately I Inadequately I Not I Not I 1 Comments Addressed Addressed Addressed Applicable I. General Location and Description A. Location 1.Township,Range,Section,%-Section X 2.Local streets within and adjacent to the development X 3.Major open channels,lakes,streams.irrigation and other water resource facilities within and adjacent to proposed X development 4.Names of surrounding developments including jurisdiction X (municipalities) B. Description of Property 1 Area in acres X 2. Ground cover X 3 Major open channels and ownership X 4 General project description X 5. Irrigation facilities and ownership information X 6. Groundwater characteristics where applicable X II. Drainage Basins and Sub-Basins A. Major Basin Description 1.Reference to Weld County Master Drainage Plan(s)where X applicable 2 Major basin drainage characteristics X 3.Identification of all irrigation facilities within 200 ft of the X property boundary B. Sub-Basin Description 1.Historic drainage patterns on the subject property and X Drainage basin delineations must be adjacent properties revisited(see comments in report). 2.Off-site drainage flow patterns and impacts on the subject X Please show contours for offsite basins property M.Drainage Design Criteria A. Discussion of the optional criteria/deviation from Weld X Discussion provided butnot approved. County CODE p rov pp B. Development Criteria Reference and Constraints 1.Discussion of previous drainage studies(i.e.project master plans)for the subject property that influence or are influenced by X the proposed drainage design for the site 2.Discussion of site constraints such as slopes,streets,utilities, Proposed development site plan impacts existing structures,and the proposed development or site plan X cannot be assessed until proposed contours impacts on the proposed drainage plan are provided. C. Hydrologic Criteria 1.Identify design rainfall(source of design storm depth X information,NOAA Atlas,UD&FCD maps,etc.) 2.Identify design storm recurrence intervals X 3.Identify runoff calculation method(s)and any computer X models 4.Identify detention discharge and storage calculation X method(s)and computer models 5 Discussion and justification of other criteria or calculation X Table SO-1 from the UD&FCD Manual does methods used not comply with Weld Co.Code. D. Hydraulic Criteria 1.Identify various capacity County References X 2.Identify detention outlet type X Please add more discussion and drawing detail to drawing sheets. 3.Identify check/drop structure criteria used X Open channels require redesign,as per 4.Discussion of other drainage facility design criteria used X redline comments. Please indicate all drainage features on drawing sheets. IV. Drainage Facility Design A. General Concept 1.Discussion of concept and typical drainage patterns I X I I (Please revisit offsite drainage. Weld County Public Works Page 1 of 2 Change of Zone Drainage Report Checklist Form Updated 01-27-2006 Comment Headings Adequately Inadequately not NotI Addressed I Addressed I Addressed I Applicable I Comments 2.Discussion of compliance with off-site runoff considerations X See redline comments. and constraints 3.Discussion of the content of all tables,charts,figures,or X Please add discussion to text about the drawings presented in the report FIRM panel(FEMA). 4.Discussion of anticipated and proposed drainage patterns X Discussed in text,but cannot be verified without proposed contour data. B. Specific Details 1.Discussion of compliance with drainage criteria(street,inlet, X Need more detail on outlets from pond,and and pipe capacities,etc.) revisit design of open channels. 2.Discussion of drainage problems encountered and solutions X Not all design points identified,and some at specific design points design points not fully discussed or drawn. 3.Discussion of detention storage and outlet design X Outlet design is incomplete. 4.Discussion of maintenance access and aspects of the design X Please include a note that Weld County will not maintain drainage related areas. V. Conclusions A. Compliance with the WCSDC B. Drainage concept 1.Effectiveness of drainage design to control damage from X storm runoff 2.Influence of proposed development on any applicable Weld X County Master Drainage Plan recommendations 3 Identification of and written approval of affected irrigation company or other property owner(s). Weld County may require that the applicant provide evidence that offsite impacted X jurisdictions have been notified of the proposed drainage plans and potential impacts. VI. References A. Reference all criteria and technical information used X Please discuss soil type selection. VII.Appendices A. Hydrologic Computations 1.Land use assumptions regarding adjacent properties X I 2 Initial and major storm runoff computations at specific design X points 3.Historic and fully developed runoff computations at specific X Please revisit historic flows. design points 5-yr B. Hydraulic Computations 1.Culvert sizing X Please add culvert sizing calcs for pond outlet and under driveway access. 2.Storm sewer sizing X 3.Street capacity evaluation X Please provide calc's and drawing for pond 4.Storm inlet sizing X outlet structure. Channel is too steep,needs lining,needs 6.Open channel sizing X freeboard,and side slopes are too steep. Please revise and check max velocity for channel lining(erosion potential). 7.Check dam and/or drop structure sizing X 8.Detention pond area/volume capacity and outlet sizing X 9.Changes to Calculation Methods—if applicant/design engineer modifies any portion of UD&FCD spreadsheets used for hydrologic or hydraulic calculations,the applicant/design All items addressed in previous checklist engineer shall identify all changes to calculation assumptions or X comments. Please review redlines in the computer programs as to type of change and specific factors report carefully. that were modified. Weld County Public Works Page 2 of 2 Change of Zone Drainage Report Checklist Form Updated 01-27-2006 PRELIMINARY DRAINAGE REPORT For Lot B of the Amended Recorded Exemption No. 0805-10-4-AMRE-3961 CHURCH BARN Prepared for: CASSEDAY CREATIVE DESIGNS, LLC 55 South Elm Avenue, Suite 210 Eaton, CO 80615 Contact: Robb Casseday (970) 454-8740 January 27, 2006 Prepared By: Drexel, Barrel! & Co. 6513 W. 4th Street Greeley, Colorado 80634 (970) 351-0645 Michael D. Walker, P.E. Engineering Manager / ) EXHIBIT n Drexel, Barre]] & Co. v Engineers/Surveyors January 27, 2006 Boulder Colorado Springs Greeley Mr. Don Carroll Weld County Engineering 6513 W.4th Street 1111 H Street Greeley.Colorado 80634 Greeley, CO 80631 970-351-0645 RE: Preliminary Drainage Report for Lot B of the Amended Recorded 970-351-0665 Fax Exemption No. 0805-10-4-AMRE-3961 (Church Barn) Dear Don: I am pleased to submit for your review and approval, this Preliminary Drainage Report for the Church Barn site. I hereby attest that this preliminary drainage design of the Church Barn site was prepared by me, or under my direct supervision, in accordance with the provisions of the Weld County Storm Manual. Sincerely, Michael D. Walker, PE No. 37687 Engineering Manager Drexel, Barrel; & Co. WCR 72 M N) M c.o 3 SITE 1 m 15 o a WCR 70 O .ti N N > O CO Drexel, Darrell & Co. \ VICINITY MAP DATE: Engineers • cu Surveyors DWG. NOT TO SCALE JOBINO:27-06 VCMAP G1480 SHEET 1 OF 1 TABLE OF CONTENTS HEADING PAGE I. INTRODUCTION A. Proposed Project Location /Description 1 B. Site Description 1 C. Existing Drainage 1 II. SCOPE OF WORK 1 III. EXISTING (HISTORIC) DRAINAGE SYSTEM A. Historic Site Drainage 2 B. Off-site Runoff 2 IV. PROPOSED DEVELOPMENT A. Criteria 2 B. Developed Runoff 2 C. Pond A Design 3 V. STORM WATER QUALITY & EROSION CONTROL 3 VI. CONCLUSION A. Drainage Concept 4 B. Compliance with Standards 4 • VII. REFERENCES 5 APPENDICES A. Hydrologic Analysis: Rational Method • Back Pocket Preliminary Drainage Plan Preliminary Drainage Report Church Barn pg 1 INTRODUCTION A. Proposed Project Location The Church Barn site is a proposed church that is located within Weld County. The project site is located in the Southeast ''A of Section 10, Township 6 North, Range 66 West, of the 6`h Principal Meridian, in the County of Weld, Colorado. The proposed development borders the northern right-of-way of Weld County Road 70 and the western right-of-way of Weld County Road 33 and agricultural land to the west, and north. B. Site Description The site consists of approximately 5.55 acres and is currently zoned for agricultural use. The proposed Church Barn site will consist of one 9,000 sq-ft building with parking and one entrance connecting to WCR 33. The church has plans to double the size of their initial building with a future phase of construction. The calculations within this report have accounted for the future phase of construction. C. Existing Drainage • The site is currently covered with native grasses. Runoff for this site generally sheet flows from the northwest to the southeast with an average slope of approximately 2.0%. Runoff from the site flows into existing roadside swales along the west edge of WCR 33 and the north edge of WCR 70. The flows are then conveyed south along the west edge of WCR 33. IL SCOPE OF WORK The intent of this report is to identify preliminary drainage patterns and calculations for the drainage design of the proposed church. This report has been prepared in a manner consistent with the Urban Storm Drainage Criteria Manual (USDCM) as well as the Weld County Development Code. G:\G1480\Preliminary Drainage1G1480 Preliminary Drainage Report.doc Preliminary Drainage Report Church Barn p,_ 2 III. EXISTING (HISTORIC) DRAINAGE SYSTEM A. Historic Site Drainage Historically, the development was composed of one drainage basin, under agricultural land use. Runoff for this site generally sheet flows from the northwest to the southeast with an average slope of approximately 2.0%. Runoff from the site flows into existing roadside swales along the west edge of WCR 33 and the north edge of WCR 70. The flows are then conveyed south along the west edge of WCR 33. B. Off-site Runoff A site visit and existing topography revealed that very little off-site runoff enters the Church Barn site. The runoff from adjacent properties generally flows from west to east, where the runoff leaves the properties in the roadside swale along WCR 33. IV. PROPOSED DEVELOPMENT A. Criteria The Church Barn site basin was less than 160 acres, thus the Rational Method was used to determine initial (5-yr) and major (100-yr) runoff volumes. The Modified Rational Method is a widely accepted predictor of flows from basins less than 160 acres in size. The rainfall intensity and runoff coefficients were determined from Figure 3-1 of the City of Greeley Storm Drainage Design Manual and Tables RO-3 and RO-5 of the revised version of Vol.1 of the June 2001 USDCM. Preliminary detention pond sizing was analyzed using the FAA Method. An overall 100-year coefficient of 0.60 was calculated, along with a 5-year historic release of 0.72 cfs to arrive at the required 100-year detention volume. B. Developed Runoff G:\G1480\Preliminary Drainage\G1480 Preliminary Drainage Report.doc Preliminary Drainage Report Church Barn Pg. 3 Development of the church will increase runoff volumes and peak flowrates to this site's historic outfall point in the southeast corner of the site. Consequently, detention will be necessary to mitigate developed flowrates to the 5-year historic rate. A detention pond (Pond A) in the southeast corner of the project will attenuate the site's runoff to the 5-year historic rate. Drainage swales, streets, and paved surfaces will be used to convey concentrated runoff across the site to the proposed detention facility. Basin Descriptions: Basin A (5.55 ac) Basin A contains the entire site and runs along the south, east, and west property lines with its northern boundary approximately 160 feet north of the proposed church. This basin generally flows from northwest to southeast to Design Point 1. The flow is collected at Design Point 1 in the detention pond (Pond A). C. Pond A Design The detention pond (Pond A) lies in the southeast corner of the site. This pond will be used to attenuate developed flows to the 5-year historic release of 0.72 cfs. The • pond will need to detain 0.80 acre-feet with 0.077 acre-feet of that being water quality volume. The release from the pond will be discharged into a roadside swale along WCR 33. V. STORMWATER QUALITY & EROSION CONTROL The overlot grading of the Church Barn site will occur during the first phase of construction. All erosion control and stormwater quality measures will be incorporated into this initial phase of construction. Structural erosion control measures will consist of silt fencing and straw bales located in design channels. All drainage improvements shall be thoroughly cleaned and inspected once construction is completed. Any disturbed areas left exposed for more than thirty days will receive native (drilled) seeding and straw mulch at 2 tons per acre, until G:\G1480\Preliminary Drainage\G1480 Preliminary Drainage Report.doc Preliminary Drainage Report Church Barn P`, 4 permanent landscaping has been provided. Vehicle tracking control will be used at construction entrances until paving operations are completed. VI. CONCLUSION A. Drainage Concept Detention will be necessary for this site to attenuate developed flowrates to the 5- year historic rate in order to mitigate downstream effects of the proposed development. The detention pond (Pond A) will detain the majority of the runoff from this site. The pond will release the 5-year historic rate off-site into the existing roadside swale along WCR 33. The preliminary storage volume for the detention pond (Pond A) is 0.80 acre-feet which includes water quality volume. The size of this pond will be refined during the final design process. B. Compliance with Standards The proposed Church Barn site does not lie within any known FIRM floodplain, and therefore it is not subject to any FEMA flood hazard regulations. This report complies with the Urban Storm Drainage Criteria Manual as well as the Weld County Development Code. G:\G1480\Preliminary Drainage\G1480 Preliminary Drainage Report.doc Preliminary Drainage Report Church Barn Pg. 5 VII. REFERENCES 1. Design Criteria and Construction Specifications — Volume II of V Storm Drainage Design Criteria Manual, City of Greeley, dated October, 1997. 2. Urban Storm Drainage Criteria Manual (USDCM), dated March, 2001. 3. Weld County Development Code. G:G14801Preliminary Drainage\G1480 Preliminary Drainage Report.doc APPENDIX A HYDROLOGIC ANALYSIS: RATIONAL METHOD G:\G1480\Preliminary Drainage\G1480 Preliminary Drainage Report.doc Drexel, Barrel) & Co. Project Job No. G N180 Lesigned r ' OL)J Date 1—Zb"J b Checked Date Sheet No. I mperv;0�) re .5=, Rocs = v c,. Li 1.3 A . S .55 A c. 2 ! 5(. r - 1 a000 f 1- ) 3-2 3.2'7 c4 = 5 .2R Ae. L F 1:� (� ,� t '.;rM Drc,lr-c,je Cr: r L ups U �. - -�./ 3 0. (3 . 5 . 55Ac - c) .77 c c:;.; 2`-1 kr. 0- t\ T, \nJCCV_ a ( c) ! J- , iq i z+ O 7 1 ) - WG� 1 ^d r } rro2(`V OvsPNes IzC. 4 B J CV= G.9�n,9I - {O �f1� ). 1 f O 78(C.`if = - .205Y C .-2,2H] p, I - S S 5 o = 0.077 AC-- 4- 1 "2- -4 Boulder Colorado Springs Greeley DRAINAGE CRITERIA MANUAL (V. 1) RUNOFF '' TABLE RO.3 Recommended Percentage Imperviousness Values Land Use or Percentage Surface Characteristics Imperviousness Business: Commercial areas 95 Neighborhood areas 85 Residential: Single-family * Multi-unit (detached) 60 Multi-unit (attached) 75 Half-acre lot or larger Apartments 80 Industrial: Light areas 80 Heavy areas 90 Parks, cemeteries 5 Playgrounds 10 Schools 50 Railroad yard areas 15 Undeveloped Areas: Historic flow analysis 2 Greenbelts, agricultural 2 Off-site flow analysis 45 (when land use not defined) Streets: Paved 100 Gravel (packed) 40 Drive and walks 90 Roofs 90 Lawns, sandy soil 0 Lawns, clayey soil 0 See Figures RO-3 through RO-5 for percentage imperviousness. Based in part on the data collected by the District since 1969, an empirical relationship between C and the percentage imperviousness for various storm return periods was developed. Thus, values for C can be determined using the following equations (Urbonas, Guo and Tucker 1990). CA = KA + (1.31i' — 1.4412 + 1.135i— 0.12) for CA≥0, otherwise CA =0 (RO-6) CCD = KCD + (0.8581' -0.7861' + 0.774i+ 0.04) (RO-7) CB = (CA + CCD)/2 in which: =% imperviousness/100 expressed as a decimal (see Table RO-3) 06/2001 RO-9 Urban Drainage and Flood Control District .,.J.' d DREXEL, BARRELL & CO. CIVIL ENGINEERS/LAND SURVEYORS Project: CHURCH BARN Job G1080 Client: CASSEDAY CREATIVE DESIGNS.LLC Designed by: MOW Dale. 1/26/06 COMPOSITE RUNOFF COEFFICIENTS Area Urban Drainage,Volume 1.Revised 2001 Table RC-5 Weighted Weighted Weighted Weighted Weighted Basin (acres) Description Percent Imp."r O2 C5 Cis Coro Cr Cs Coo Coo Imperv. 1.87 Roadways/Curb 8 Gutter 100% 0.89 0.90 0.92 0.96 0.30 0.30 0.31 032 33.7% Basin 0.00 Concrete Sidewalk Area 90% 0.71 0.73 0.75 0.81 0.00 0.00 0.00 0O0 0O% A 041 Roofs 90% 071 0.73 075 0.81 0O5 0.05 0.06 0.06 6.7% Developed 3.27 Landscape/Open Space 2% 0.03 0.09 0.17 0.36 0.02 0.05 0.10 021 1.2% A=5.55 5.55 <<Total Area Total Weighted Runoff Coefficients Cr,C5.C,5,Cmo&I" D.37 0.41 0.47 0.60 41.5% DRAINAGE CRITERIA MANUAL (V. 1) RUNOFF 50 30 /11/ { = 20 l j �v✓ W v e 4W! C.1 JW `.p * W • a• .63 C+ C. c C. 3 10 .• S J s _ v p (y, • a *Ir r V W ,=Ov ' a�4 �O `ii • a p Pp v .; ;f v .J5 p f N Q f ai O 4,p pa3 W 4f i b a » 4� qt 3 __ a a vi W e 0e 4 O . 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CIVIL ENGINEERS/LAND SURVEYORS Project: CHURCH BARN JOB# G1480 Client: CASSEDAY CREATIVE DESK By: MOW Date: 1/26/2006 DETENTION POND SIZING (FAA METHOD)100-YEAR EVENTfDEVELOPED) POND 1 AREA(AC) 5.55 C(100)= 0.60 C(100)*A= 3.33 OUTFLOW ADJUSTMENT FACTOR (K)= 1.0 100 YEAR RELEASE RATE (CFS) = 0.7 STORAGE VOLUME=(TIME x C x A x I)-(TIME x RELEASE RATE) STORM CUMULATIVE 100 YEAR 100 YEAR 100 YEAR REQUIRED REQUIRED REMARKS DURATION DURATION PRECIPITATION INFLOW RELEASE STORAGE STORAGE TIME TIME INTENSITY VOLUME VOLUME VOLUME VOLUME (min) (sec) (in/hr) (ft^3) (ft^3) (ft^3) (ac-ft) 5 300 9.67 9660 216 9444 0.217 10 600 7.51 15005 433 14572 0.335 15 900 6.34 19001 649 18352 0.421 20 1200 5.34 21339 866 20473 0.470 25 1500 4.74 23676 1082 22594 0.519 30 1800 4.39 26314 1299 25015 0.574 40 2400 3.59 28691 1732 26960 0.619 50 3000 3.10 30969 2165 28805 0.661 60 3600 2.78 33327 2597 30729 0.705 80 4800 2.16 34525 3463 31062 0.713 100 6000 1.79 35764 4329 31435 0.722 100-YR REQUIRED VOLUME 120 7200 1.50 35964 5195 30769 0.706 150 9000 1.23 36863 6494 30370 0.697 180 10800 1.05 37762 7792 29970 0.688 240 14400 0.81 38841 10390 28452 0.653 300 18000 0.66 39560 12987 26573 0.610 360 21600 0.57 40999 15584.4 25415 0.583 480 28800 0.44 42198 20779.2 21419 0.492 600 36000 0.36 43157 25974.0 17183 0.394 720 43200 0.31 44595 31168.8 13427 0.308 840 50400 0.27 45315 36363.6 8951 0.205 960 57600 0.24 46034 41558.4 4476 0.103 840 ' 50400 0.27 45315 36363.6 8951 0.205 1080 64800 0.21 45315 46753.2 -1439 -0.033 1200 720O0 0.19 45554 51948.0 -6394 -0.147 1320 79200 0.17 44835 57142.8 -12308 -0.283 1440 86400 0.16 46034 62337.6 -16304 -0.374 STORMWATER QUALITY MANAGEMENT DRAINAGE CRITERIA MANUAL(V. 3) 0.50 � I 0.45 40-hour Drain Time 0.40 24-hour Drain Tim 0.35 a L I 0.30 WOCV=a'(0.91i°-1.1912+O.7888 -a 6-hr drain time a=0.7 y 0.25 12-hr drain time a =0.8 24-hr drain time a =0.9 40-hr drain time a = 1.0 0.20 i o 0.15 12-hour Drain Time 0.10 6-hour Drain Time 0.05 0.00 i 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Total Imperviousness Ratio(i=1,..91100) FIGURE SQ-2 Water Quality Capture Volume(WQCV), 80th Percentile Runoff Event SQ-24 9-1-99 Urban Drainage and Flood Control District STORAGE DRAINAGE CRITERIA MANUAL (V. 2) attempt to account for the effects of the WQCV on all control levels whenever it performs watershed-level drainage and flood control system master plans. 3.2 Sizing of On-Site Detention Facilities 3.2.1 Maximum Allowable Unit Release Rates for On-Site Facilities. The maximum allowable unit release rates per acre for on-site detention facilities for a number of design return periods are listed in Table SO-1. These rates apply unless other rates are recommended in a District-approved master plan. The predominant soil group for the total tributary catchment shall be used for determining the allowable release rates. Multiply the unit rates provided in Table SO-1 by the tributary catchment's area to obtain the actual design release rates in cubic feet per second (cfs). Whenever Natural Resources Conservation Service (NRCS)soil surveys are not available for the portion of a county being studied, extrapolate their types using soil investigations at the site. • TABLE SO-1 Recommended Maximum Allowable Unit Flow Release Rates (cfs/acre) of Tributary Catchment Design Return NRCS Hydrologic Soil Group Period (Years) A B C 8 D 2 0.02 0.03 0,04 5 0.07 0.13 0.17 10 0.13 0.23 0.30 25 0.24 0.41 0.52 50 0.33 0.56 0.68 100 0.50 0.85 1.00 3.2.2 Empirical Equations for the Sizing of On-Site Detention Storage Volumes. Urbonas and Glidden (1983), as part of the District's ongoing hydrologic research, conducted studies that evaluated peak storm runoff flows along major drainageways. The following set of empirical equations provided preliminary estimates of on-site detention facility sizing for areas within the District. They are not intended for use when off-site inflows are present or when multi-stage controls are to be used (e.g., 10- and 100- year peak control) at the storage facility. In addition, these equations are not intended to replace detailed hydrologic and flood routing analysis, or even the analysis using the Rational Formula-based FAA method for the sizing of detention storage volumes. The District does not promote the use of these empirical equations. It does not object, however, to their use by local governments who have adopted them or want to adopt them as minimum requirements for the sizing of on-site detention for small catchments within their jurisdiction. If the District has a master plan that contains specific guidance for detention SO-8 06/2001 Urban Drainage and Flood Control District PRELIMINARY DRAINAGE REPORT For Lot B of the Amended Recorded Exemption No. 0805-10-4-AMRE-3961 CHURCH BARN Prepared for: CASSEDAY CREATIVE DESIGNS, LLC 55 South Elm Avenue, Suite 210 Eaton, CO 80615 Contact: Robb Casseday (970) 454-8740 Revised March 24, 2006 Prepared By: Drexel, Barren & Co. 6513 W. 4th Street Greeley, Colorado 80634 (970) 351-0645 Michael D. Walker, P.E. Engineering Manager EXHIBIT TABLE OF CONTENTS HEADING PAGE I. INTRODUCTION A. Proposed Project Location/Description 1 B. Site Description 1 II. SCOPE OF WORK 1 III. EXISTING (HISTORIC) DRAINAGE SYSTEM A. Historic Site Drainage 1 _ B. Off-site Runoff 2 IV. PROPOSED DEVELOPMENT A. Criteria 2 B. Developed Runoff 3 C. Pond A Design • C3 V. STORM WATER QUALITY & EROSION CONTROL 3 VI. CONCLUSION A. Drainage Concept 4 B. Compliance with Standards 4 VII. REFERENCES 4 APPENDICES A. Mapping B. Hydrologic Analysis: Rational Method C. Detention Pond Analysis Back Pocket Preliminary Drainage Plan Drainage Basin Plan Preliminary Drainage Report Church Barn Pg. 1 I. INTRODUCTION A. Proposed Project Location The Church Barn site is a proposed church development that is located within Weld County. The project site is located in the Southeast % of Section 10, Township 6 North, Range 66 West, of the 6`h Principal Meridian, in the County of Weld, Colorado. Proposed development borders the northern right-of-way of Weld County Road (WCR) 70 and the western right-of-way of WCR 33 and agricultural land to the west, and north. See Appendix A—Mapping: Vicinity Map. B. Site Description The proposed site consists of approximately 5.55 acres and is currently zoned for agricultural use. Proposed development will consist of one 9,000 sq-ft building with parking and one entrance connecting to WCR 33. Church owners have plans to double the size of their initial building with a future phase of construction. Calculations within this report have accounted for the future phase of construction. II. SCOPE OF WORK The intent of this report is to identify preliminary drainage patterns and calculations for the drainage design of the proposed church property. This report has been prepared in a manner consistent with the Urban Storm Drainage Criteria Manual (USDCM) as well as the Weld County Development Code. III. EXISTING (HISTORIC) DRAINAGE SYSTEM A. Historic Site Drainage Historically, the development was composed of one drainage basin, under agricultural land use. Runoff for this site generally sheet flows from the northwest to the southeast with an average slope of approximately 2.0%. Runoff from the site flows into existing roadside swales along the west edge of WCR 33 and the north edge of WCR 70. Flows are then conveyed south along the west edge of WCR 33. G:\G14801Preliminary Drainage1G1480 Preliminary Drainage Report(rev 3-22-06).doc / T\ Preliminary Drainage Report Church Barn Pg. 2 B. Off-site Runoff Off site flow from the north will enter the proposed project site according to United States Geological Service (USGS) topographic quad maps. Rather than have this flow be conveyed across the proposed Church Barn project site, a ditch is proposed for the north side of the road that feeds the project site from WCR 33. Estimated 100-Year runoff to this ditch is estimated to be 40.1 cfs. Utilizing Haestad Methods hydraulic computer program, FlowMaster, a trapezoidal ditch section with 2 to 1 side slopes and a 2-foot bottom width was modeled. Estimated flow depth will be 2-feet. Flow from the ditch will enter the borrow ditch along WCR 33. Flow from this basin (Basin B) is conveyed to this borrow ditch under existing conditions, therefore, the proposed drainage ditch will not adversely impact downstream conveyance. See Appendix A — Mapping: Drainage Basin & Flow Path Plan for information pertaining to offsite flow patterns. IV. PROPOSED DEVELOPMENT A. Criteria The Church Barn site basin was less than 160 acres, thus the Rational Method was used to determine initial (5-yr) and major (100-yr) runoff volumes. Utilization of the Modified Rational Method is a widely accepted predictor of flows from drainage basins comprising areas less than 160 acres in size. Rainfall intensity and runoff coefficients were determined from Figure 3-1 of the City of Greeley Storm Drainage Design Manual and Tables RO-3 and RO-5 of the revised version of Vol.1 of the June 2001 USDCM (See Appendix B — Hydrologic Analysis: Rational Method). Preliminary detention pond sizing was analyzed using the FAA Method. An overall 100-year coefficient of 0.57 was calculated, along with a 5-year historic release of 0.80 cfs to arrive at the required 100-year detention volume. A detention volume was also analyzed using Haestad Methods computer program Pond 2. The inflow hydrograph for this analysis was based on the Modified Rational Method. Pond information was entered into the program, which reflected the proposed geometry indicated in Appendix A—Mapping: Drainage & Erosion Control Plan. Side slopes for the pond were assumed to be 4:1. Utilizing this information, a pond comprising a volume of 0.60 acre-ft was estimated to account for detention and water quality. Typically, the Rational Method Hydrograph would not be used for final detention design, but it provides an independent check for the FAA results. Results from this G:\G1480\Preliminary Drainage\G1480 Preliminary Drainage Report(rev 3-22-06).doc /` Preliminary Drainage Report Church Barn Pg. 3 -- analysis show that the results from the FAA analysis are reasonable. Upon final detention pond sizing, analysis will evaluate the inflow hydrographs in association with development of outlet structures. The outlet structure will be a combination of an orifice (Approximately 4-inches) which will regulate smaller flows through the pond. A small weir will be placed a few feet higher than the orifice to help regulate higher flow rates. B. Developed Runoff Development of the church will increase runoff volumes and peak flowrates to this site's historic outfall point in the southeast corner of the site. Consequently, detention will be necessary to mitigate developed flowrates to the 5-year historic rate. A detention pond (Pond A) in the southeast corner of the project will attenuate the site's runoff to the 5-year historic rate. Drainage swales, streets, and paved surfaces will be used to convey concentrated runoff across the site to the • proposed detention facility. Basin Descriptions: Basin A (6.16 ac) _ Basin A contains the entire site and runs along the south, east, and west property lines with its northern boundary approximately 160 feet north of the proposed church. This basin generally flows from northwest to southeast to Design Point 1. Flow is collected at Design Point 1 in the detention pond(Pond A). C. Pond A Design The detention pond (Pond A) lies in the southeast corner of the site. This pond will be used to attenuate developed flows to the 5-year historic release of 0.80 cfs. The pond will need to detain approximately 0.84 acre-feet with 0.082 acre-feet of that being water quality volume. Release from the pond will be discharged into a roadside swale along WCR 33. V. STORMWATER DUALITY & EROSION CONTROL _ The over lot grading of the Church Barn site will occur during the first phase of construction. All erosion control and stormwater quality measures will be incorporated into this initial phase of construction. Structural erosion control measures will consist of silt fencing and straw bales located in design channels. All G:\G1480\Preliminary Drainage G1480 Preliminary Drainage Report(rev 3-22-06).doc /T\ Preliminary Drainage Report Church Barn Pg. 4 drainage improvements shall be thoroughly cleaned and inspected once construction is completed. Any disturbed areas left exposed for more than thirty days will receive native (drilled) seeding and straw mulch at 2 tons per acre, until permanent landscaping has been provided. Vehicle tracking control will be used at construction entrances until paving operations are completed. VI. CONCLUSION — A. Drainage Concept Detention will be necessary for this site to attenuate developed flowrates to the 5- - year historic rate in order to mitigate downstream effects of the proposed development. The detention pond (Pond A) will detain the majority of the runoff from this site. The pond will release the 5-year historic rate off-site into the existing roadside swale along WCR 33. The preliminary storage volume for the detention pond (Pond A) is 0.84 acre-feet which includes water quality volume. The size of this pond will be refined during the final design process. B. Compliance with Standards The proposed Church Barn site does not lie within any known FIRM floodplain, and therefore it is not subject to any FEMA flood hazard regulations. This report complies with the Urban Storm Drainage Criteria Manual as well as the Weld County Development Code. VII. REFERENCES 1. Design Criteria and Construction Specifications — Volume II of V Storm Drainage Design Criteria Manual, City of Greeley, dated October, 1997. 2. Urban Storm Drainage Criteria Manual (USDCM), dated March, 2001. 3. Weld County Development Code. G:\G1480\Preliminary Drainage\G1480 Preliminary Drainage Report(rev 3-22-06).doc /\ APPENDIX A MAPPING G:\G1480\Preliminary Drainage\G1480 Preliminary Drainage Report(rev 3-22-06).doc ............. 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II 7i I I W 11 • Ii o 7 r7)--/Z____—11 to APPENDIX B HYDROLOGIC ANALYSIS: _ RATIONAL METHOD G:1G1480\Preliminary Drainage\G1480 Preliminary Drainage Report(rev 3-22-06).doc /T\ DRAINAGE CRITERIA MANUAL (V. 1) RUNOFF r ) TABLE RO-3 Recommended Percentage Imperviousness Values Land Use or Percentage Surface Characteristics Imperviousness Business: Commercial areas 95 Neighborhood areas 85 Residential: Single-family Multi-unit (detached) 60 Multi-unit (attached) 75 Half-acre lot or larger Apartments 80 Industrial: Light areas 80 • • Heavy areas 90 Parks, cemeteries 5 Playgrounds 10 Schools • 50 - • Railroad yard areas 15 Undeveloped Areas: Historic flow analysis 2 Greenbelts, agricultural 2 Off-site flow analysis 45 (when land use not defined) Streets: _ Paved 100 Gravel (packed) 40 Drive and walks 90 Roofs 90 Lawns, sandy soil 0 Lawns, clayey soil 0 * See Figures RO-3 through RO-5 for percentage imperviousness. Based in part on the data collected by the District since 1969, an empirical relationship between C and the percentage imperviousness for various storm return periods was developed. Thus, values for C can be determined using the following equations (Urbonas, Guo and Tucker 1990). CA = KA + 1.3113 — 1.4412 + I.135i—0.12) for CA ≥0, otherwise CA = 0 (RO-6) CCD = KCD + (0.85813 - 0.786i2 + 0.774i+ 0.04) (RO-7) Ca — (CA + CCD)/2 in which: i= % imperviousness/100 expressed as a decimal (see Table RO-3) 06/2001 RO-9 Urban Drainage and Flood Control District < aea a eo ass. -Fs 9 ('R0. 0. 0) O a r N O aV t a) 0 0 aJ r N- O O lsir N- O a t7 N) E N N O O CO b , 0 0 0 m CO .2 8 0 0 0 0 6 0 0 0 0 O cr)a)0 of O )O r g a a V O o O N O O r V , 000 •-- N L e 0 0 0 0 O >0 0 0 0 O 5o -o ro moo m o0 am O N0 a O m :`O O O O N- E. O0 O O O ' 0 0 0 6 6 0 ma 00 m p ,<, ,. — N O N 0 0 0 ilt in I'. 0 0 0 CO O 2 0 0 0 0 O 'I O O O a O # y Oa o m _ O CO f0 A .:a CO A a m CO a') A ::m m m CO A 80000 Y(. 6666 ca— d 8 8 O ' O N N V) N U N U) V) N U Orr O r N- 0 0 0 0 6 0 6 0 0 6 0 U . 0 a 0 5.a m in c d N 0 N- CO 0 0 0 h N 0 u C 0 4 0 0 0 0 0 0 0 0 — 'y CL 0 a) ,O — a) a) O 0 a /'� co F O r r fC p o) r O] a co O 6 o O c OJ N-0 6 0 NO = or a 66 0 6 0 6 a o N 9 9 9 m Q CD .2 ' L N 0 r 0 m a)a) E o 0 0 o m a ' m C4 E a) Or m m N I- :.O m Q) N F- U O a) J > a a — Q 0 ra o?j fvs m a, a) a) 0 N a ra A o m o a) U ..... a z w 0 0 W Qad a cC x to - t4 N . Q = U a ; at) i. fl 3 aC) FFN'ayl ch C a v O m I:.o a a co • W m } CI m a) m Q m CO m 2 — QC W S Q 3 d U m CO m U m U Q -00 ,- -0 N 0 9 0 — to W z▪ H K w 0 0 8 F- A C 0 D F- z w K O cc J v cc O a J V x W V 0 8 V 0 ' 8 0 r O^) 0 - [y] a V .. 0 E - 00, M6 O O r r O) RS m C O a) ¢ N AU `a0 . CC e - c c �I�}\ m m < -aa) a mm .X Q o w �•y DRAINAGE CRITERIA MANUAL (V. 1) RUNOFF - 50 - 30 3 / i 20 Io c 3 r" W Q awe • 1 . ^We W • `r •;b i — n t0 Wet 3 a Z a ct ."'• o a o f 'u, • a 3 r a =0 f ♦W • r,� 0 O 5 coa y Wb I. v • to) ao �a of it o 3 W o — W -a 'J 4? a 4 t • 4v Q 3 ' I o• f v°f 4,` = A cr I ? :� .t O W 3 N 0 — ¢ 2 a ro ly2 f y I iv I- a rf Q r0 3 ,W — 1I I if I I I .5 .1 .2 .3 .5 1 2 3 5 10 20 — VELOCITY IN FEET PER SECOND FIGURE RO-1 Estimate of Average Overland Flow Velocity for Use With the Rational Formula — 06/2001 RO-13 Urban Drainage and Flood Control District 0 z Y F N Q m j' Q D Z Z Z . ' .— K z m m m O co — reO JQ `ry Z H - >" � rn LL III - > Ol LL N U m D Z w v m x — CO m U 4 O Z H 5 4, N¢ Z CC H Q D u O (7 F Z n p o — J W 1/� O cn 0 J W t Z a C m E W W Z `° C ' o N Z LL Z Z r } W Co O C W ~ U v Z m N _ - - Q U O O v V.. {L O 7-4 0 0 D W Q O F m "E' ` a co- - F.. O Z F- d Q Q Z K F W E } ~ W a . W V d m a Z U Q o O N oV . 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Z %/Bed ro Q < m m 1NIOd • N NOIS30 _ � W C N • N al V N Worksheet Church Barn: Trapezoidal Channel Project Description Worksheet Church Barn Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth Results Depth 1.93 ft Flow Area 11.3 ft2 Wetted 10.65 ft Perimeter • Top Width 9.73 ft Critical Depth 1.49 ft Critical Slope 0.020466 fUft Velocity 3.57 ft/s - Velocity 0.20 ft Head Specific 2.13 ft Energy Froude 0.58 Number Flow Type Subcritical 1.93 ft ft Section Data V:1 N H:1 Mannings 0.035 NTS Coefficient Slope 0.006 ft/ft 500 Depth 1.93 ft Left Side Slope 2.00 H : V Right Side 2.00 H : Slope V Bottom Width 2.00 ft Discharge 40.50 cfs Project Engineer: Drexel Barrell Church Barn.fm2 Drexel Barrell&Co. FlowMaster v6.1 [614k] 3/23/2006 8:33:02 AM ©Haestad Methods, Inc. 37 Brookside Road Waterbury,CT 06708 USA (203)755-1666 Page 1 APPENDIX C DETENTION POND ANALYSIS G:\G1480\Preliminary Drainage\G1480 Preliminary Drainage Report(rev 3-22-06).doc /T\ - Drexel,'r,,�Barrell & Co. Project (iLk t�C..yn Sy,y S Job No. C;1926 ^ 'Rv igned 1r[ Date 5-22-or., Checked Date Sheet Na. 1.�Qc.fN lwb✓1L`f/S - . = / ACOCett C5,N7 fah - h = 81,373 ,27 UZ = /.87 t - ..4ancke-A fe- = /G.9013. 93 sitz = 3.98 aarc5 43.)4, acn tt m r7-64.0 Arta S - darn '7aba -9 t-tr bavv n'icOMina'G C".tara;c. h%nva1 tZ Syr `15;fc. 3 Sb / = th% - O. 13 . to,/&) af,ned _ 0.80 c..444 t Water (4,..0.1 4/ / 3 WqC / = aC, (0.91 ; - 1, 11;Z + o, 75;) MctiherArat rne. e4 GC. z. 0.g der 2Hke OainT:Jet L = 21-feru;Ou5 t�i4k O.9 0,91(43.374655 - 1,/9G0,n/c + be" I GO,97e) ©, E0 nc�c6 Val Q Gy = o./40 in:. to,/6 ct re.5 . z - /\No? z 0. 0 sez. a eta•ct Boulder Colorado Springs Greeley A DREXEL BARRELL & CO. CIVIL ENGINEERS/LAND SURVEYORS Project: CHURCH BARN JOB# G1480 — Client: CASSEDAY CREATIVE DESI(By: MDW Date: 1/26/2006 Rev By: RCM Rev.Date: 3/22/2006 DETENTION POND SIZING(FAA METHOD)100-YEAR EVENT(DEVELOPED) POND 1 AREA(AC) 6.16 C(100)= 0.57 C(100)*A= 3.51 OUTFLOW ADJUSTMENT FACTOR(K)= 1.0 100 YEAR RELEASE RATE(CFS) = 0.8 STORAGE VOLUME=(TIME x C x A x I)-(TIME x RELEASE RATE) STORM CUMULATIVE 100 YEAR 100 YEAR 100 YEAR REQUIRED REQUIRED REMARKS DURATION DURATION PRECIPITATION INFLOW RELEASE STORAGE STORAGE TIME TIME INTENSITY VOLUME VOLUME VOLUME VOLUME (min) (sec) (in/hr) (ft^3) (ft^3) (ft^3) (ac-fl) 5 300 9.67 10186 240 9946 0.228 10 600 7.51 15821 480 15341 0.352 15 900 6.34 20035 720 19315 0.443 20 1200 5.34 22500 960 21540 0.494 25 1500 4.74 24965 1200 23765 0.546 30 1800 4.39 27746 1440. 26306 0.604 40 2400 3.59 30252 1920 28332 0.650 50 3000 3.10 32654 2400 30254 0.695 60 3600 2.78 35140 2880 32260 0.741 80 4800 2.16 36404 3840 32564 0.748 • 140 6000 1.79 37710 4800 32910 0.756 100-YR REQUIRED VOLUME 120 7200 1.50 37921 5760 32161 0.738 150 9000 1.23 38869 7200 31669 0.727 180 10800 1.05 39817 8640 31177 0.716 240 14400 0.81 40955 11520 29435 0.676 300 18000 0.66 41713 14400 27313 0.627 360 21600 0.57 43230 17280.0 25950 0.596 480 28800 0.44 44494 23040.0 21454 0.493 600 36000 0.36 45505 28800.0 16705 0.383 720 43200 0.31 47022 34560.0 12462 0.286 840 50400 0.27 47780 40320.0 7460 0.171 960 57600 0.24 48539 46080.0 2459 0.056 840 50400 0.27 47780 40320.0 7460 0.171 1080 64800 0.21 47780 51840.0 -4060 -0.093 1200 72000 0.19 48033 57600.0 -9567 -0.220 - 1320 79200 0.17 47275 63360.0 -16085 -0.369 1440 86400 0.16 48539 69120.0 -20581 -0.472 r. • CHURCHP.OUT POND-2 Version: 5.20 S/N: CHURCH BARN DETENTION POND CALCULATED 03-22-2006 16:26:49 DISK FILE: c:\church\POND1 .VOL _ Planimeter scale: 1 inch = 1 ft. * Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum (ft) (sq.in.) (acres) (acres) (acre-ft) (acre-ft) 4,812.40 8,500.00 0.20 0.00 0.00 0.00 4,813.00 9,900.00 0.23 0.63 0.13 0.13 4,814.00 12,000.00 0.28 0.75 0.25 0.38 4,815.00 15,400.00 0.35 0.94 0.31 0.69 4,816.00 17,700.00 0.41 1.14 0.38 1.07 _ 2 IA = (sq. rt(Areal) + ((Ei-E1)/(E2-E1))*(sq. rt(Area2)-sq. rt(Areal))) where: El, E2 = Closest two elevations with planimeter data Ei = Elevation at which to interpolate area Areal,Area2 = Areas computed for El, E2, respectively IA = Interpolated area for Ei * Incremental volume computed by the Conic Method for Reservoir volumes. volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq. rt. (Areal*Area2)) where: EL1, EL2 = Lower and upper elevations of the increment Areal,Area2 = Areas computed for EL1, EL2, respectively U Volume = Incremental volume between EL1 and EL2 Page 1 PONDOUT.OUT POND-2 Version: 5.20 S/N: »»> OUTFLOW HYDROGRAPH ESTIMATOR ««< Inflow Hydrograph: c:\church\BASA-IN .HYD Qpeak = 25.2 cfs Estimated Outflow: c:\church\ESTIMATE.EST Qpeak = 0.8 cfs Approximate Storage Volume (computed from t= 0.00 to 0.50 hrs) 0. 5 acre-ft 0 Page 1 STORMWATER QUALITY MANAGEMENT DRAINAGE CRITERIA MANUAL (V. 3) 0.50 0.45 I40-hour Drain Tim- _ 0.40 24 hour Drain Timc+4N p-47 0.35 0 .c 9 0.30 wocv=agosv'a.1si'.o.7a4 ✓ 6-hr drain time a=0.7 y 0 25 12-hr drain time a=0.8 24-hr drain time a=0.9 40-hr drain time a = 1.0 • 0.20 • _ a /3 0.15 12-hour Drain Time — 0.10 6-hour Drain Time 0.05 0.00 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Total Imperviousness Ratio(i=1„„1100) FIGURE SQ-2 Water Quality Capture Volume(WQCV),80th Percentile Runoff Event • SQ-24 9-1-99 Urban Drainage and Flood Control District • STORAGE DRAINAGE CRITERIA MANUAL (V. 2) attempt to account for the effects of the WQCV on all control levels whenever it performs watershed-level drainage and flood control system master plans. 3.2 Sizing of On-Site Detention Facilities 3.2.1 Maximum Allowable Unit Release Rates for On-Site Facilities. The maximum allowable unit release rates per acre for on-site detention facilities for a number of design return periods are listed in Table SO-1. These rates apply unless other rates are recommended in a District-approved master plan. The predominant soil group for the total tributary catchment shall be used for determining the allowable release rates. Multiply the unit rates provided in Table SO-1 by the tributary catchment's area to obtain the actual design release rates in cubic feet per second (cfs). Whenever Natural Resources Conservation Service (NRCS)soil surveys are not available for the portion of a county being studied, extrapolate their types using soil investigations at the site. TABLE SO-1 Recommended Maximum Allowable Unit Flow Release Rates (cfs/acre) of Tributary Catchment Design Return NRCS Hydrologic Soil Group Period (Years) A B C & D 2 0.02 0.03 0.04 5 0.07 0.13 0.17 10 0.13 0.23 0.30 25 0.24 0.41 0.52 50 0.33 0.56 0.68 100 0.50 0.85 1.00 3.2.2 Empirical Equations for the Sizing of On-Site Detention Storage Volumes. Urbonas and Glidden (1983), as pad of the District's ongoing hydrologic research, conducted studies that evaluated peak storm runoff flows along major drainageways. The following set of empirical equations provided preliminary estimates of on-site detention facility sizing for areas within the District. They are not intended for use when off-site inflows are present or when multi-stage controls are to be used (e.g., 10- and 100- year peak control) at the storage facility. In addition, these equations are not intended to replace detailed hydrologic and flood routing analysis, or even the analysis using the Rational Formula-based FAA method for the sizing of detention storage volumes. The District does not promote the use of these empirical equations. It does not object, however, to their use by local governments who have adopted them or want to adopt them as minimum requirements for the sizing of on-site detention for small catchments within their jurisdiction. If the District has a master plan that contains specific guidance for detention SO-8 06/2001 Urban Drainage and Flood Control District File contains oversized map Please see original file Page 1 of 2 Brad Mueller From: Brian Varrella Sent: Tuesday, April 04, 2006 3:12 PM To: Brad Mueller Cc: Peter Schei; Donald Carroll Subject: RE: USR-1540 Church Barn review Brad, Thanks for your e-mail. You are correct—the review comments for AmRE-3961 apply to USR-1540. I chose to refer to the AmRE number since it was the only project number referenced on the cover of the drainage report. Our review has shown that the applicant has not provided adequate materials for a complete USR application under Weld County CODE 23-2-240(A.5), and we would like the applicant to re-submit prior to scheduling before the Board. I spoke with Peter about the drainage maintenance comment, and we think it should be added to the USR and RE. I will meet with Don tomorrow about the wording, and see if we can get something to you as soon as possible. I hope this answers your questions. Please contact me if there is anything else I can help you with. I will send you another e-mail as soon as Don and I can figure out the wording for maintenance requirements. Brian Brian K. Varrella, P.E. Weld County Public Works 1111 H Street Greeley, CO 80632 phone: 970-304-6496, ext. 3741 fax: 970-304-6497 bvarrella@co.weld.co.us r************************* From: Brad Mueller Sent: Tuesday, April 04, 2006 1:50 PM To: Brian Varrella Subject: USR-1540 Church Barn review Brian, Thanks for providing comments concerning the Church Barn application. Although your comments cite the Amended Recorded Exemption (AmRE-3961), I assume that they also apply to the USR-1540 also in process. In fact, the USR application is the one that has a condition prior to hearing, so it is the one for which the review ism most important. H }� Your comments indicate that the report does not sufficiently address drainage issues and needs to be re- mom) submitted. Can you please clarify whether this re-submittal is required prior to our scheduling this before the K W 04/05/2006 Yr,.,,, ed Page 2 of 2 Board, or would you accept a re-submittal as part of a condition of approval by the Board before recording the plan? We have no bias either way, but I will need to convey to the applicant what is required of them. There is also a comment about the drainage being maintained by the owner. If you have specific notes that should go on the USR (and/or RE), please let me know. You might find it easiest to coordinate those through Don for format, transfer of info to our office, etc., but I'll take them if you want them in any form. Thanks again. I'll contact the owner with these changes and the re-submittal requirements after I hear back from you. Brad 04/05/2006 BOARD OF COUNTY COMMISSIONERS' SIGN POSTING CERTIFICATE THE LAST DAY TO POST THE SIGN IS June 2, 2006. THE SIGN SHALL BE POSTED ADJACENT TO AND VISIBLE FROM A PUBLICALLY MAINTAINED ROAD RIGHT-OF-WAY. IN THE EVENT THE PROPERTY BEING CONSIDERED FOR A SPECIAL REVIEW IS NOT ADJACENT TO A PUBLICALLY MAINTAINED ROAD RIGHT-OF-WAY, THE DEPARTMENT OF PLANNING SERVICES SHALL POST ONE SIGN IN THE MOST PROMINENT PLACE ON THE PROPERTY AND POST A SECOND SIGN AT THE POINT AT WHICH THE DRIVEWAY (ACCESS DRIVE) INTERSECTS A PUBLICALLY MAINTAINED ROAD RIGHT-OF-WAY. .rte o /wa rc , HEREBY CERTIFY UNDER PENALTIES OF PERJURY THAT THE SIGN WAS POSTED ON THE PROPERTY AT LEAST TEN DAYS BEFORE THE BOARD OF COMMISSIONERS HEARING FOR THE CHURCH BARN USE BY SPECIAL REVIEW IN THE AGRICULTURAL ZONE DISTRICT. Name of Person Posting Sign Signature of Person Posting Sign STATE OF COLORADO ss. COUNTY OF WELD Tv (�� ll The foregoing instrument was subscribed and sworn to me this day of i C l , 204O WITNESS my hand and official seal. 141 Notary Public v WENDI INLOES NOTARY^UBLIC My Commission Expires: STATE OF COLORADO OMIT LL' l , • i - I I\ • I_ I f - - f q � Ir�.._• - _ _ 1 1 Jr 44 Mileasina--sallialli l .rte♦�. -. _-.Mi l ll 1 I _ •_- f-- �'\' •r tom-"=-rr♦_•_`.. .•.... - ,- , - - - r• • -. ,. +t•=. - " _ t,ta = -• F � • -.. - _ .4. - " >- •�. --rf•- Wit, .\.-,. - • • . • 1 it'.n. r .I.". ��' r w� t „ .• ~�.rs`a .. ftpSd ' a " ti ,~ .' ' f (� . a5 ii�+ r l.` IIC/` 'v.' �./ ��'r•'�' w v r t •,1' - .. ..1n f f' '� r - • �Vf, ' J 'I,"7' �� ^l - •►:';r -„ � r . 4 , ;! � r �t :•.a.--.4 • R " f _ _ • �►'• .30••-.. -..► {•� .� - a• ./ -r .!' '� Irit' \`_ 'f'- Y�y f Lam" '` 7- ja\ wa f k - l , - ys -Q� _ •i _ •r6a, r�� s . \ - n : • > - -: •r Y - - ' c•' •Z_ f rS"af • nr L ' .,(f--.74--Tr; x.. •- 1; ° 1•.mat.-. IL �a ,4 ,�� 't �� qtr j=• . 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S �. r ,rte, - 7{�.i- L r. .J.rd~••.. �rJ1' 1[J, •�• •{ `�• `�T0If4. /•R' 1't1 y:.... , .�'" - '"� ti ,�. rf- - -- - r[. ._ ._Ia ' .. 4....•^.� .war�. �. 1.' �!'I.T,��.a...-—�La1 .1. _. -.'�'l :. 1 r i L•'.f.� ...s_ - - a. �'' vs ne } -- z. ..751 ...... � i�........:zI -•aM�n�=_. • aIlk I NOTICE , A MIX SEAAAIC CIIIEEIIISC'i IRIS PROPERTY MILL BE SRI At.: Was Can w...*.t '1S 1O"Aer,Guam, r.T1nu1'L./.nunro- n . ur flvs AJO s_. • Cal x USR-15.10'Etas _ • EM MIE AIEMYAAM CALL _ - WELD COUNT ORPIMENT Of�A r• MARISMC SERVICES At I (1711153-1111nl JSI 4 20©6/05:/23 p' .. ♦.- _.. z 3 tr i..s%� fg a s �'.'�, `. . k', a �� 3i h +: ;+°A a ✓3 t ,, -,-,"...1“,'.. r` ,.-?`-4 r�� ' git 20.14...^.3 „, f+ Y `!{4 �,Yc S r₹ §'t' g�.,t s`rd xs S + i n 1,. a y, y e.r r ti £ ry :` � } r � ' "ran: fii � 'ku,�., } 1 �' 4 .. i.�:r i�rr; Y r q i rT9 l k' ••• � ;� • a,n • V. • • • • • • . a • • • Hello