The URL can be used to link to this page

Browse Search

Home My WebLink About20141527.tiff CHANGE OF ZONE DRAINAGE INVESTIGATION for NORTH COUNTRY - P. U. D. to be located in the West Half of the Northwest Quarter of Section 7, Township 3 North, Range 68 West of the 6t" P. M ., Weld County, Colorado Prepared for: JOHN FRITS 16898 Weld County Road 1 Longmont, Colorado 80504 February 2014 Project No. 1018 - GRD - 13 Prepared by: DENNIS R. MESSNER, P. E. 1355 N. Cleveland Ave., Ste #1 Loveland, Colorado 80537 Telephone: (970) 461 -3501 Dennis R. Messner P. E. Consulting Civil Engineer Project No. 1018 - GRD - 13 February 5, 2014 John Frits 16898 Weld County Road 1 Longmont, Colorado 80504 Dear Mr. Frits, The enclosed report represents the results of the Change of Zone Drainage Investigation for the proposed "North Country - P. U. D." to be located on Lot B of Recorded Exemption 1207-07-02 RECX11 -0002 that is situated in the West Half of the Northwest Quarter of Section 7, Township 3 North, Range 68 West of the P.M. , Weld County, Colorado. This investigation was based upon the proposed site development plan; on-site observation; and available topographic information. The investigation was performed according to the criteria established by Weld County. Thank you for the opportunity to be of service. If you should have any questions, please feel free to contact this office. Respegfrully Submitted,"1"ViAtt":1/4eDennis R. Messner, P. . Consulting Civil Engineer "I hereby state that this Change of Zone Drainage Investigation for "North Country - P. U. D. " was prepared by me or under my direct supervision for the owners thereof and meets or exceeds the criteria established by Weld County." POO R • •.••... • b �1 ; . • Dennis ' ; rrss ' 9 �': Registerd, Gfessional p!, ; • =, State ofIONAL 4 o.ua.?6 ��• �- 2 - S' if 1355 N. Cleveland Ave., Ste #1 * Telephone: (970) 663-2221 * Loveland, Colorado 80537 TABLE OF CONTENTS Description Pale LETTER OF TRANSMITTAL i TABLE OF CONTENTS ii & iii I . GENERAL LOCATION AND DESCRIPTION A. Location 1 B. Description of Property 1 II. DRAINAGE BASINS AND SUB-BASINS A. Major Basin Description 2 B. Sub Basin Description 2 III . DRAINAGE DESIGN CRITERIA A. Development Regulations and Criteria Reference 3 B . Development Constraints 3 C . Hydrologic Criteria 3 IV. DRAINAGE FACILITY DESIGN A. General Concept 3 B. Specific Details 4 V. EROSION CONTROL C. General Concept 4 VI . CONCLUSIONS A. Compliance with Standards 5 B. Drainage Concept 5 C. Recommendations 5 VII. REFERENCES 6 TABLE OF CONTENTS (CONTINUED): EXHIBITS Vicinity Map Existing Conditions Exhibit Proposed Conditions Exhibit APPENDIX I Drainage Summary Drainage Calculations APPENDIX II Charts, Graphs, and Figures Details General Location and Description: A. Location 1 . The proposed "North Country - P.U.D. " is Lot B of Recorded Exemption 1207-07-02 RECX 11 -0002 located in the West Half of the Northwest Quarter of Section 7, Township 3 North, Range 68 West of the 6`h P.M. in Weld County, Colorado. 2. The site is more specifically located at the east side of County Line Road (Weld County Road # 1 ) and the south side of Weld County Road #36. (Refer to the included Vicinity Map.) B. Description of property 1 . The "North Country - P.U.D. " property consists of approximately 39.4 acres. a. The site has a single family residence that is under construction and an agricultural out building. The balance of the site is non-irrigated farmland. Wheat is the primary crop that has been grown on the site. 2. The "Soil Survey of Weld County, Colorado" prepared by the U.S. Department of Agriculture, Soil Conservation Service, indicated that the surface soils consist of "Nunn clay loam", "Wiley-Colby complex", "Colby loam" and "Shingle loam." a. The Nunn clay loam soil type is described as a deep, well-drained soil that formed in mixed alluvium and eolian deposits. The "Soil Survey" identifies the surface runoff potential as low, and the hazard of erosion as slight. b. The soil typical of the Wiley-Colby complex series is described as a deep, well- drained soil that formed in calcareous eolian deposits. The "Soil Survey" identifies the surface runoff potential as medium and the hazard of erosion as moderate. c. The soil typical of the Colby loam soil type is described as a deep, well-drained soil that formed in calcareous eolian deposits. The "Soil Survey" identifies the surface runoff potential as rapid and the hazard of erosion as high. d. The soil typical of the Shingle loam soil type is described as a shallow, well- drained soil that formed in residuum from shale. The "Soil Survey" identifies the surface runoff potential as medium to rapid and the hazard of erosion as moderate. 3 . The site is generally considered relatively flat with slopes ranging from 1 % to 5%. 4. The proposed development is to consist of two (2) single family residential lots, that are to be approximately 19.7 acres each. Access to each lot is to be provided to each lot from existing driveways from County Line Road . 5 . 1 II. Drainage Basins and Sub-basins: A. Major Basin Description 1 . The property is not located within an officially designated drainage basin. The site is located at the crest of a drainage basin that drains to the north and discharges into the Ish Ditch. The basin extends north to the Little Thompson River. 2. The site is not located within a designated flood way or flood plain. B. Sub-basin Description 1 . The existing drainage pattern of the site is to generally flow from southwest to northeast. 2. Based upon the USGS Quad sheet for the area and topographic survey information for Recorded Exemption RECX 11 -0002, the site receives off-site runoff from the area to the south. This off-site area is divided into two sub-basins. The western sub-basin, Basin " 1 -OS", comprises approximately 10. 15 acres of undeveloped land located immediately east of County Line Road that drains toward County Line Road. Runoff from this area drains to the north along the east side of County Line Road. Off-site area " 1 -OS" produces approximately 6.6 c.f.s. during the 5-year storm and 19. 1 c.f.s. during the 100-year storm. The eastern sub-basin, Basin "2-OS", comprises approximately 49.85 acres of undeveloped land located to the east of Basin " 1 -OS". This area drains to the north to a point near the Northeast corner of Lot A of Recorded Exemption RECX 11 -0002. Off-site Basin "2-OS" produces approximately 20.0 c.f.s. during the 5-year storm and 72.5 c.f.s. during the 100-year storm. 3 . The western on-site basin is identified on the Existing Drainage Exhibit as Sub-Basin 'A'. This basin drains from south to north along County Line Road. The basin contains approximately 25 .8 acres. The sub-basin produces approximately 19.97 c.f.s. during the 5- year storm and 70.46 c.f.s. during the 100-year storm. 4. The combined runoff from the off-site area " 1 -OS" to the south and on-site Sub-Basin "A" is estimated to be approximately 20.00 c.f.s during the 5-year storm and 58.69c.f.s. during the 100-year storm. 5. The southeastern on-site basin is identified on the Existing Drainage Exhibit as Sub- Basin `B '. This basin drains from southwest to northeast and flows to a natural drainage course. The basin contains approximately 9.9 acres. The drainage course leaves the site on the eastern boundary approximately 400 feet north of the southeast corner of the site. Sub- Basin "B" produces approximately 7.91 c.f.s. during the 5-year storm and 23.75 c.f.s. during the 100-year storm. 6. The northeastern on-site basin is identified on the Existing Drainage Exhibit as Sub- Basin 'C '. This basin drains from south to north and flows to the north side of Weld County Road 36. The run-off then flows easterly along the south side of Weld County road 36. The basin contains approximately 3 .8 acres. Sub-Basin "C" produces approximately 4.48 c.f.s. during the 5-year storm and 11 .64 c.f.s. during the 100-year storm. 2 III. Drainage Design Criteria: A. Development Regulations and Criteria Reference 1 . The Urban Drainage and Flood Control District Storm Drainage Criteria along with Weld County's "Addendum to the Urban Storm Drainage Criteria Manuals - Volumes 1 , 2 and 3, Weld County Code Article XI and Appendix 8L" were utilized to perform the drainage analysis. B. Development Constraints 1 . The historic drainage pattern of the site will be maintained. Any grading in conjunction with the site development will conform with the existing slope and grades as closely as possible. 2. The drainage impact of this site will not adversely affect existing roads, utilities or downstream irrigation facilities. C. Hydrological Criteria 1 . The Rational Method was used for determining peak flows at various concentration points. The NOAA Precipitation-Frequency Atlas 2 of the Western United States, Volume II was utilized to determine the 1 -hour point rainfall depths. a. The 5-year, 1 -hour rainfall depth is 1 .43 inches while the 10-year and 100-year values are 1 .73 and 2.70 inches, respectively. a. In calculating the time of concentration for the proposed conditions, the same equation for the undeveloped conditions was used since the developed conditions apply to more densely populated urban conditions. b. The Hydrological Classifications for the on-site soils are both Type 'B ' and Type 'C' . The Type 'C' was used in peak runoff calculations to produce a more conservative drainage design. 2. The Weld County Criteria calls for the initial and major storm design frequencies of 5 and 100-years. a. The peak runoff rates for the site and ofd site area were calculated using the 5 and 100-year rainfall intensities. 3 . The contents in the tables, charts, and figures presented in this report, come from the Urban Storm Drainage Criteria Manual. These diagrams facilitated in the drainage design calculations. IV. Drainage Facility Design: A. General Concept 3 1 . Surface runoff from the proposed street area and residential lots will flow overland and discharge to the properties to the north and east in the same pattern as during the existing conditions. B. Specific Details 1 . The western on-site basin is identified on the Proposed Drainage Exhibit as Sub-Basin "A". This basin drains from south to north along County Line Road. The basin contains approximately 25.8 acres. The sub-basin produces approximately 20.25 c.f.s. during the 5- year storm and 70.79 c.f.s. during the 100-year storm. 2. The combined runoff from the ofd site area " 1 -OS" to the south and on-site Sub-Basin "A" is estimated to be approximately 20. 19 c.f.s during the 5-year storm and 58.94 c.f.s. during the 100-year storm. a. Driveway culverts will be required for Lots 1 and 2. The minimum culvert diameter is 15 inches. No development is anticipated in Sub-Basin "B" or Sub-Basin "C". Therefore, no change in the rate of run-off is anticipated 3 . The development of the property will result in an increase of the overall percentage of imperviousness from 45 .93% to 46.65%. a. The increase in imperviousness, and subsequent increase in runoff, results from considering the proposed construction of houses and associated improvements. The result is an increase of 1 .6% imperviousness. b. The proposed development will nevertheless produce more runoff to a certain degree, however, detention or stormwater quality facilities would not be a practical concept for this property. Routing flows over such a large area to a detention or stormwater quality pond would be a major undertaking since the anticipated flow patterns will cause runoff to flow overland uniformly and not concentrate a specific points. The long overland flow path will act as a "buffer" to promote filtration, infiltration, and settling of sediment to reduce runoff pollutants. V. Erosion Control: A. General Concept 1 . Erosion control considerations have been made based upon the short term, during construction activities, and the long term, when development of the subdivision is complete. 2. The long term measures incorporated to eliminate erosion are the anticipated methods and materials to be used to provide the ground surface covering at the driveways and the landscaped areas. The residential structures and surrounding hard-surfaced areas will provide a deterrent to erosion. The establishment of pasture, lawns and the combination of landscape plantings and ground covers will aid in deterring erosion. 4 3 . The recommended short term erosion control method to be incorporated into the construction requirements for the project is the placing of sediment control devices such as "Wattles" and "Straw Bale Dikes". These are being recommended in order to prevent debris and sediment from flowing from the areas disturbed by construction activities on-site to the adjacent properties. 4. Wind erosion control measures have not been recommended for the site. It is anticipated that the disturbed area will be open and subject to wind action for an extremely short time. If blowing dust is a problem, a combination of surface roughening and water application is to be used to control the dust. VI. Conclusions: A. Compliance with Standards 1 . All drainage design conforms to the requirements of the Urban Drainage and Flood Control District Storm Drainage Criteria along with Weld County's "Addendum to the Urban Storm Drainage Criteria Manuals - Volumes 1 , 2 and 3, Weld County Code Article XI and Appendix 8L". 2. Proposed erosion control measures conform to the recommendations presented in Volume III of the Urban Storm Drainage Criteria Manual and generally accepted erosion control procedures. B. Drainage Concept 1 . This drainage design and sketch plan report for the "North Country - P.U.D." is considered preliminary. The final drainage report will update these concepts and present the final design details for the necessary drainage improvements. C. Recommendations 1 . A roadside ditch and driveway culverts will be required to route stormwater along the east side of County Line Road at the designated driveway locations. 2. Erosion control measures will be incorporated during the construction activities to deter erosion and sediment from being deposited on adjacent properties. 3 . The off-site runoff that travels through the site historically will not pose a threat to the proposed residential structures. 4. The development of the property will result in a slight increase of runoff, however, stormwater detention is not recommended at this time. 5 VII . References: A. "Urban Storm Drainage Criteria Manual", Current Revision. B. "Weld County Storm Drainage Criteria Addendum to the Urban Storm Drainage Criteria Manuals — Volumes 1 , 2, and 3 , Weld County Code Article XI and Appendix 8L," Current Revision. C. "Soil Survey of Southern Weld County Area, Colorado", United States Department of Agriculture, September 1980. 6 EXHIBITS \V T.\ (CT_X-------' _:-/r leil N. I \ \..,,,,,--- --.,,,, \-_,\N5 / it \ ' . II y�CR . 36 � —�- � \140\____ir ,., , r r , N.< . inciyar . _ , , , „\y,,,,,______,_F_ _ i ..„ , V ) 1 ) .. O%-db //,,4 - 1 1 ., - ---<- N i - t � ) 9 3 Lot A � / ' � � RE 1207T07-02 � RECX11 -OOO2 I in i/ 7-7 (1'i1 '. Re; owero 1 : s/se WASATCH '' OADQ � (:Thij 0 I / / ' ri Lg ;- gr*/ 1- J � h / I In § 1 W R34 sieol ' � - � siae SZ,6 i,,N.S,\N\ / * *** ---- I \ \ \ \ \ . . .& .5-/ \ i NORTH COUNTRY - P . U . D . VICINITY MAP Not — to — Scale l OSc— l9i7(OL6) -auoydalal opP.zojo3 'Aluno3 pp LcS08 opoJoloO `puolano3 Q11d — A&LN1100 HIHON 1 C\, I l #•a}S "am?' puolana10 •N ccn1 suompuo3 uilSIX3 o i 4igiux3 aeuiPJQ 31111 z > 0 aaaut6u3 IV!3 6ui}jnsuo3 - Q 2 o ; 6 o 1 1 .o .zaussa soma S ►LIMA NHOf w J ' d ' 2� . Q Q z Y , = � I :1N3110 o fl) o 6 c1) c O i o w N ILI 4C 0�J t0 tp O O H d + N o (0 !� M O �! ca N (p C a) O J t.Nt. O� h N N e� '+J o -pc M N e- (- O — 'a -c C o 0 Q 0 x � 0 w CO LsJ C 0 N 0 OO J 0 0 � � C � _ ed V C 5 � Q •o t0 C Yeti co O O O Qf v o w o C 0 i Z - - 'et O '6 .O o a O c a � � (a a' N 72 N r! a D m at +1 c a on Z 2 .7 p E 7) C c d 0 0v co Q & 0 C c Fieo Qo o II II II II pCC vc! r. co C °,7):41O O 1�0 0 1-- 0 < m — 0 Q H <t- in c=i 9,A / V) o a o v j - w W ") N u; Z :Q c II: Q ~ + O k m C) H ~ m O u.in u. U. V p - O W O '7) C 0 - ina Q N ED U o , I Jif ( I ( .-+ ?/C ) I O - ;i I ® 2o )/ 7f ; jU \ \ \ \, . „ I . v f ___________— cc, ,n ,_ I .... ' 1 1 ( k \ s 8 \ \ \ HI a4 \ �� 7 Io - c � I� -- 4II \ 1\ \?(LdE 1 , o \ m -\ / ') 1 ,8K' loZ L „OZ ,S .L8 , _...----- _______,___:,..j \\\ �l l 1 , 1 ,��. \ 4. \ 4-- \ ___ \ c i \ 2 The, \ /t \ 1 --- ct\J D � w \\ \ o ` �� / 7 O 11. i_ / h. \ S i I ) � ~ I 7/1 O m � o 4:11 --7 1 to j 4'\ •10.9 \ / i / c LI a i / \ ',................... ,. 1 // o O cO -I- 0 / ) y , / //,/ , , j ,, IT / / i / / I / _}// 7 -Thti / , 1 — r:a (Nicr%' --------/Y/ r-- --- Z / / / ;/ 7 /\ ( m e // �1 • RD :_II °�' a �s x I W a , V ° 0 \ s , �� ...--"'"---:....--5-7 / - �_I r2 L , i� T / 0 . 1 \-- --) / wi r____________ ___ ____ „........M" ..4%..: ICI 7 \ A /0 a: I :.51.. N _______ ic op H.......,........... t Z \ \ \ ., 1 /r___ _......„c ______ __ __ _________ ___________ f; (7, ---,....„.... ,......_ x 7O 1 ___ / �/ ,/ 4/0 al ._,, 1- it , / ___-- => -_----/__ _......---- ..i<es# I I 1 / i ( ./..„:--/---, sib, --_________N\ /2 3 N, c— ----- � + 1 \\ et ' ----„..._ ,Thr aki -.. , L.N___ "Nx \cic- r------ . i G - - I -N-- er-\ I .• 9£ Prod A2unoD PPM ,80'86 l ' l 3 „t0 ,Z0.92 N l 0Sc— L 9t'(0L6) -auoydalal opPJojo3 'di.uno3 pp LcS09 opomlo0 'puolano3 and — A≥LLNf100 HIHON ,� C\ I l #•a}S "am?' puolana10 •N ccc1 suoilipuoD pasodold o 4igiuxa a2uiP.JQ :31111 z > 0 aaaut6u3 IV!3 6u !linsuo3 • Q js o ; 6 O l 1 •o F- .zaussa soma S ,LIMA NHOf a o w ' � ' d ' 2� Q Q Q Y 0 _ (NI :1N3110 o cUn o 6 c1) c ` O i oILI _ 4C Off' O 0) Chi C H d a) O h tp c ea a.cu 0 �V.. NN h N 6 r +' 0 -c C N cp M N e- (1 Z , ° 0 — • -0 c 0 0 Q O x � o w N W C 0 :co N 0 UN OO J 0 0 � � C am =+C (r0 '•1 Ln CI 0 U C 0 Q) Q CL Q nO. la N cb a o 0 o 16 .2 oo c C 0 c a to N N Z2 N v c D Co at +' c a cn T512 0 0 v m Q o 0 C >" c Qo ,E2 Q0 o o II II ll II q ,p v i ti co Q? ao 00 1-O 0 F O < m — 0 CQ � O N M v. Qi el Q ‹-t- '14:3 U) c.i - / Cl) a v La w W N Z :Q c IW. Q ~ + O k m C) H ~ C LL O u. � V p p W Ca <- Q - N Lq - a a o O \ Le; I I I i I f ( ( y , / . / I I/C ) (e.( (�� \ ) ) / i / ! A ® / (v 1 U v. In ( / / , 1 I i ( ;15' \ \ \ \ \ 1 \ I N / i 1 ( k \ x -. Q ' \ o 4 7 / YI2S , ______eil \ w \\ \ % O m _\ / s1/ \) ' � ,9c• loZ L g.0Z ,5 .L8 ....___--. _______,..„3/42...j 1 h \ \ l l 1 , \ 0. p. \ \ .-- \ \ i i ' as,c; 0 \ ,, % .-----____J—, I z \ / \ . de \ \_Z ------- C:6:\/ o\z"- a / 'II o \\ , \ 1 #I �-� ,� CO r I \ 0 SS / �' Iii JT f J 00 - - rn1 / ii CD to S \ / 71 \ so \ 1 'trio tu • o to / / / /11/ tl b a:) y 0 - T / / 7 17 i — ' �y 7/7 _______, Z c\I \1 Ir-I- 0 2, „ / // II /// •@ 7 i 2 ----=_- _ / \ \JI \ .1 / u -0 A ( ` , .1_ 2 ._ v 0 0 w ,__ ___:___....________i___________ / m ______ e N s ..............., 1 \ �` J —� i a2 -:-51-- �� - ---------------:::;:11:\H Ncv � a ,l 00 (flI. n �— 00 O \ �\ / rr--- � - -- \ `� /Ho ______- __His.. ..:....---Z._____. -------__. \ °I I / i ( r-A %-- -------- __----dit"....---.--- -N\ /, I- La N c—- ---------— �..........yp# i a a kJ '‘-- • L?-----.3_x \cic--/- . . cle \ , I -N-- er-\ �� r� VIII '� ,�� 9£ pEo j A2uno3 PPM ,90'861 l 3 .170 ,Z0.92 N APPENDIX I DRAINAGE CALCULATIONS EXISTING CONDITION OFFSITE DRAINAGE BASINS Area-Weighting for Runoff Coefficient Calculation Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE - 1 -OS Illustration inea %Arta. LEGEND: Flow Direction 4 a .. tom Cat chin ent Subarea :3 Boundary Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres Coeff. A C* CA input input input output Field 9.39 45.00 I 422.55 Pavement 0. 54 100.00 53.78 Gravel 0.21 40. 00 8.54 Roof 0. 01 90.00 0.90 sum: 10.15 Sum: 485.76 Area-Weighted Runoff Coefficient (sum CA/sum A) = 47.85 *See sheet "Design Info" for inperviousness-based runoff coefficient values. 10YR EX OFFSITE 1 -OS .xls, Weighted C 11 /07/2013, 16: 11 :20 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE - '1 -OS' (5 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = #1 -A Area = 10. 15 Acres Percent Imperviousness = 47.85 % N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 5 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .43 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.34 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.34 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 (--r' (_ Beginnin^ _ -__— F1ow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.34 N/A 0.26 25.92 1 0.0120 70 15.00 1 .64 0.71 ' 2 ' 0.0040 525 15.00 0.95 9.22 3 0.0110 270 15.00 1 .57 2.86 4 5 Sum_ 1 ,265 Computed Tc = 38.72 Regional Tc = 17.03 User-Entered Tc = 17.03 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 1 .92 inch/hr Peak Flowrate, Qp = 6.58 cfs Rainfall Intensity at Regional Tc, I = 3.05 inch/hr Peak Flowrate, Qp = 10.46 cfs Rainfall Intensity at User-Defined Tc, I = 3.05 inch/'hr Peak Flowrate, Qp = 10.46 cfs 5YR EX OFFSITE 1 -OS.xls , Tc and Peak() 11/07/2013, 15:49:41 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE - '1 -OS' (10 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = #1 -OS Area = 10. 15 Acres Percent Imperviousness = 47.85 % N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 10 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .73 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.39 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.34 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 (--r' (_ Beginnin^ _ -__— Flow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.34 N/A 0.26 25.92 1 0.0120 70 15.00 1 .64 0.71 ' 2 ' 0.0040 525 15.00 0.95 9.22 3 0.0110 270 15.00 1 .57 2.86 4 5 Sum_ 1 ,265 Computed Tc = 38.72 Regional Tc = 17.03 User-Entered Tc = 17.03 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.32 inch/hr Peak Flowrate, Qp = 9.30 cfs Rainfall Intensity at Regional Tc, I = 3.69 inch/hr Peak Flowrate, Qp = 14.77 cfs Rainfall Intensity at User-Defined Tc, I = 3.69 inch/'hr Peak Flowrate, Qp = 14.77 cfs 10YR EX OFFSITE 1 -OS.xls , Tc and Peak() 11/07/2013, 16:11 :20 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE - '1-OS' (100 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = #1 -OS Area = 10. 15 Acres Percent Imperviousness = 47.85 % NRCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 100 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 2.70 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.52 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.34 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 (--r' (_ Beginnin^ _ -__— Flow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.34 N/A 0.26 25.92 1 0.0120 70 15.00 1 .64 0.71 ' 2 ' 0.0040 525 15.00 0.95 9.22 3 0.0110 270 15.00 1 .57 2.86 4 5 Sum_ 1 ,265 Computed Tc = 38.72 Regional Tc = 17.03 User-Entered Tc = 17.03 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 3.63 inch/hr Peak Flowrate. Qp = 19.06 cfs Rainfall Intensity at Regional Tc, I = 5.76 inch/hr Peak Flowrate. Qp = 30.28 cfs Rainfall Intensity at User-Defined Tc, I = 5.76 inch/'hr Peak Flowrate, Qp = 30.28 cfs 100YR EX OFFSITE 1 -OS.xls , Tc and PeakQ 11/07/2013, 16:17:14 Area-Weighting for Runoff Coefficient Calculation Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE -'2-OS' Illustration inea LEGEND: Flow Direction 4 .. a tom Cat chin ent Subarea :3 Boundary Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres : Coeff. A C* CA input input input output Field 49.85 a. 45.00 I 2243.25 sum: 49.85 sum: 2243.25 Area-Weighted Runoff Coefficient (sum CA/sum A) = 45.00 *See sheet "Design Info" for inperviousness-based runoff coefficient values. 5YR EX OFFSITE 2-OS .xls . Weighted C 11 /07/2013, 15:53:06 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE - '2-OS' (5 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = #2-OS Area = 49.85 Acres Percent Imperviousness = 45.009/0 N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period, Tr = 5 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .43 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.37 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 --k' (_) Beginnin^ ( _ -__— F1ow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf Wit ft C-5 fps minutes input input output input output output Overland 0.0300 : 400 0.37 N/A 0.36 18.29 1 0.0135 605 5.00 0.58 17.36 _2 ' 0.0075 360 5.00 0.43 6 13.86 3 0.0100 200 5.00 0.50 6.67 _4 0.0180 ' 220 5.00 0.67 5.47 5 0.0036 545 5.00 0.30 30.28 Sum 2.330 I Computed Tc = 91 .91 Regional Tc = 22.94 User-Entered Tc = 22.94 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 1 .08 inch/hr Peak Flowrate, Qp = 19.97 cfs Rainfall Intensity at Regional Tc, I = 2.61 inch/hr Peak Flowrate, Qp = 48.51 cfs Rainfall Intensity at User-Defined Tc, I = 2.61 inch/hr Peak Flowrate, Qp = 48.51 cfs 5YR EX OFFSITE 2-OS.xls , Tc and PeakQ 11/07/2013, 15:53:06 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE - '2-OS' (10 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = #2-OS Area = 49.85 Acres Percent Imperviousness = 45.009/0 N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 10 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .73 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.44 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 --k' (_ Beginnin^ ( —__ F1ow Direction 4 Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf Wit ft C-5 fps minutes input input output input output output Overland 0.0300 : 400 0.37 N/A 0.36 18.29 1 0.0135 605 5.00 0.58 17.36 _2 ' 0.0075 360 5.00 0.43 6 13.86 3 0.0100 200 5.00 0.50 6.67 _4 0.0180 ' 220 5.00 0.67 5.47 5 0.0036 545 5.00 0.30 30.28 Sum 2,330 I Computed Tc = 91 .91 Regional Tc = 22.94 User-Entered Tc = 22.94 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 1 .30 inch/hr Peak Flowrate, Qp = 28.31 cfs Rainfall Intensity at Regional Tc, I = 3.16 inch/hr Peak Flowrate, Qp = 68.78 cfs Rainfall Intensity at User-Defined Tc, I = 3.16 inch/'hr Peak Flowrate, Qp = 68.78 cfs 10YR EX OFFSITE 2-OS.xls , Tc and Peak() 11/07/2013, 16:11 :53 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE - '2-OS' (100 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = #2-OS Area = 49.85 Acres Percent Imperviousness = 45.009/0 NRCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 100 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 2.70 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.59 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 --k' (_) Beginnin^ ( _ -__— F1ow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf Wit ft C-5 fps minutes input input output input output output Overland 0.0075 ' 400 0.37 N/A 0.23 28.89 1 0.0100 65 5.00 0.50 2.17 _2 ' 0.0180 220 5.00 0.67 6 5.47 3 0.0100 95 5.00 0.50 3.17 :4 0.0036 545 5.00 0.3030.28 5 Sum 1 ,325 Computed Tc =' 69.97 Regional Tc = 17.36 User-Entered Tc = 17.36 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.46 inch/hr Peak Flowrate, Qp = 72.50 cfs Rainfall Intensity at Regional Tc, I = 5.71 inch/hr Peak Flowrate, Qp = 168.46 cfs Rainfall Intensity at User-Defined Tc, I = 5.71 inch/'hr Peak Flowrate, Qp = 168.46 cfs 100YR EX OFFSITE 2-OS.xls , Tc and PeakQ 11/07/2013, 16:17:57 ONSITE DRAINAGE BASINS Area-Weighting for Runoff Coefficient Calculation Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'A' (EXISTING CONDITIONS) Illustration sir LEGEND: Flow Direction 4 a .. tom Cat chin ent Subarea :3 Boundary Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres Coeff. A C* CA input input input output Field 24.69 45.00 I 1111 .01 Pavement 0.40 100.00 39.57 Gravel 0.60 40. 00 23.94 Roof 0. 12 90.00 10.49 sum: 25.80 Sum: 1185.01 Area-Weighted Runoff Coefficient (sum CA/sum A) = 45.93 *See sheet "Design Info" for inperviousness-based runoff coefficient values. 5YR EX ONSITE A.xls. Weighted C 11 /07/2013, 15:54: 14 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - A (5 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 25.80 Acres Percent Imperviousness = 45.9394D N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 5 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .43 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.33 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ Reach 2 J (_ Beg ^innin ( _ —__— Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0210 400 0.33 N/A 0.31 21 .84 1 0.0210 300 15.00 2.17 2.30 2 0.0500 660 15.00 3.35 3.28 3 4 5 Sum_ 1 ,360 Computed Tc = 27.42 Regional Tc = 17.56 User-Entered Tc = 17.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.36 inch/hr Peak Flowrate, Qp = 19.97 cfs Rainfall Intensity at Regional Tc, I = 3.01 inch/hr Peak Flowrate, Qp = 25.39 cfs Rainfall Intensity at User-Defined Tc, I = 3.01 inchr'hr Peak Flowrate, Qp = 25.39 cfs 5YR EX ONSITE A.xls , Tc and PeakQ 11/07/2013, 15:54:14 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'A' (10 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = #'A' Area = 25.80 Acres Percent Imperviousness = 45.9394D N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 10 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .73 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.39 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ Reach 2 J (_ Beg ^innin ( Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flowl Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf Wit ft C-5 fps minutes input input output input output output Overland 0.0210 400 0.33 N/A 0.31 21 .84 1 0.0210 300 15.00 2.17 2.30 2 0.0500 660 15.00 3.35 3.28 3 4 5 Sum_ 1 ,360 Computed Tc = 27.42 Regional Tc = 17.56 User-Entered Tc = 17.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.86 inch/hr Peak Flowrate. Qp = 28.42 cfs Rainfall Intensity at Regional Tc, I = 3.64 inch/hr Peak Flowrate. Qp = 36.15 cfs Rainfall Intensity at User-Defined Tc, I = 3.64 inch/'hr Peak Flowrate, Qp = 36.15 cfs 10YR EX ONSITE A.xls , Tc and PeakQ 11/07/2013, 16:12:59 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'A' (100 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 25.80 Acres Percent Imperviousness = 45.93 % N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 100 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 2.70 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.59 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.38 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ Reach 2 J (_ Beg ^innin ( _ —__— Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf Wit ft C-5 fps minutes input input output input output output Overland 0.0210 400 0.38 N/A 0.33 20.44 1 0.0210 300 15.00 2.17 2.30 2 0.0500 660 15.00 3.35 3.28 3 4 5 Sum_ 1 ,360 Computed Tc =' 26.02 Regional Tc = 17.56 User-Entered Tc = 17.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 4.60 inch/hr Peak Flowrate, Qp = 70.46 cfs Rainfall Intensity at Regional Tc, I = 5.68 inch/hr Peak Flowrate, Qp = 86.96 cfs Rainfall Intensity at User-Defined Tc, I = 5.68 inch/'hr Peak Flowrate, Qp = 86.96 cfs 100YR EX ONSITE A.xls , Tc and PeakQ 11/07/2013, 16:18:41 Area-Weighting for Runoff Coefficient Calculation Project Title: NORTH COUNTRY ESTATES - PUD Catchment ID : OFFSITE - A + ONSITE - A Illustration 3��3- tir y LEGEND: Flow Direction % •lbw" 4 : Catchmentclam 5ubaiea 3 Boundary Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres Coeff. A C* CA input input input output Field 34.08 45.00 1533.60 Pavement 0.94 100 .00 94.00 Gravel 0.81 40.00 32.40 Roof 0. 13 90.00 11 . 70 sum: 35.96 Sum: 1671 .70 Area-Weighted Runoff Coefficient (sum CA/sum A) = 46.49 *See sheet "Design Info" for inperviousness-based runoff coefficient value 100YR EX OFFSITE 1 -OS + ONSITE A.xls, Weighted C 11 /8/2013, 3: 12 PM CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE '1 -OS' + ONSITE 'A' (5 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 35.95 Acres Percent Imperviousness = 46.49 N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 5 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .43 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.33 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 --r' (_ Beginnin^ ( _ -__— F1ow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.33 N/A 0.25 26.17 1 0.0120 70 15.00 1 .64 0.71 ' 2 ' 0.0040 525 15.00 0.95 9.22 ' 3 0.0110 270 15.00 1 .57 2.86 4 0.0210 700 15.00 2.17 5.37 5 0.0500 660 15.00 3.35 3.28 Sum 2,625 Computed Tc = 47.61 Regional Tc = 24.58 User-Entered Tc = 24.58 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 1 .68 inch/hr Peak Flowrate, Qp = 20.00 cfs Rainfall Intensity at Regional Tc, I = 2.52 inch/hr Peak Flowrate, Qp = 29.87 cfs Rainfall Intensity at User-Defined Tc, I = 2.52 inch/'hr Peak Flowrate, Qp = 29.87 cfs 5YR EX OFFSITE 1 -OS + ONSITE A.xls , Tc and PeakQ 11/07/2013, 15:58:42 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE 1 -OS + ONSITE 'A' (10 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 35.95 Acres Percent Imperviousness = 46.49 N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 10 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .73 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.39 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 --r' (_ Beginnin^ ( _ -__- F1ow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftift ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.33 N/A 0.25 26.17 1 0.0120 70 15.00 1 .64 0.71 ' 2 ' 0.0040 525 15.00 0.95 9.22 ' 3 0.0110 270 15.00 1 .57 2.86 4 0.0210 700 15.00 2.17 5.37 5 0.0500 660 15.00 3.35 3.28 Sum 2,625 Computed Tc = 47.61 Regional Tc = 24.58 User-Entered Tc = 24.58 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.04 inch/hr Peak Flowrate, Qp = 28.40 cfs Rainfall Intensity at Regional Tc, I = 3.04 inch/hr Peak Flowrate, Qp = 42.42 cfs Rainfall Intensity at User-Defined Tc, I = 3.04 inch/'hr Peak Flowrate, Qp = 42.42 cfs 10YR EX OFFSITE 1 -OS + ONSITE A.xls , Tc and Peak() 11/07/2013, 16:09:28 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE 1 -OS + ONSITE 'A' (100 YEAR STORM PROPOSED CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 35.95 Acres Percent Imperviousness = 46.49 % NRCS Soil Type = B A, B, C. or D II. Rainfall Information I (inch/hr) = C1 * P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 100 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 2.70 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.51 Overide Runoff Coefficient. C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient, C-5 = 0.33 Overide 5-yr. Runoff Coefficient. C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration �) overland LEGEND Reach 1 flab Reach 2 .41,; t` Beginning ( r__- Flow Direction „--‘7,-- it i Catchment Reach 3 Boundary kr- NRCS Land Heavy Tillage! Short Nearly Grassed Paved Areas & Type Meadow Fluid Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways (Sheet Flow) Conveyance 2.5 5 7 10 15 _ 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ft/ft ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.33 N/A 0.25 26.17 1 0.0120 70 15.00 1 .64 0.71 2 0.0040 525 15.00 0.95 9.22 3 0.0110 270 15.00 i 1 .57 2.86 4 0.0210 700 15.00 2.17 5.37 5 0.0500 660 15.00 3.35 3.28 Sum 2,625 Computed Tc = 47.61 Regional Tc = 24.58 User-Entered Tc = 24.58 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 3.18 inch/hr Peak Flowrate. Qp = 58.69 cfs Rainfall Intensity at Regional Tc, I = 4.75 inch/hr Peak Flowrate, Qp = 87.66 cfs Rainfall Intensity at User-Defined Tc. I = 4.75 inch/hr Peak Flowrate. Qp = 87.66 cfs 100YR EX OFFSITE 1 -OS + ONSITE A.xls, Tc and PeakQ 11/8/2013, 3:12 PM Area-Weighting for Runoff Coefficient Calculation Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'B' (EXISTING CONDITIONS) Illustration inea %Arta. _____- -f___ ---�—_— LEGEND: Flow Direction 4 a .. tom Cat chin ent Subarea :3 Boundary Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres Coeff. A C* CA input input input output Field 9.90 45.00 I 445.50 Pavement 0. 00 100.00 0.00 Gravel 0.00 40. 00 0.00 Roof 0. 00 90.00 0.00 Sum: 9.90 Sum: 445.50 Area-Weighted Runoff Coefficient (sum CA/sum A) = 45.00 *See sheet "Design Info" for inperviousness-based runoff coefficient values. 5YR EX ONSITE B .xls, Weighted C 11 /07/2013, 15:54:44 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'B' (5 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = B' Area = 9.90 Acres Percent Imperviousness = 45.00 % N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 5 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .43 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.37 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND Reach 1 flow _ Reach 2 Beg ^innin ( Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0150 265 0.37 N/A 0.24 18.71 1 0.0200 295 5.00 0.71 6.95 2 0.0170 260 5.00 0.65 6.65 3 4 5 . . Sum__ 820 Computed Tc = 32.31 Regional Tc = 14.56 User-Entered Tc = 14.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.15 inch/hr Peak Flowrate, Qp = 7.91 cfs Rainfall Intensity at Regional Tc, I = 3.29 inch/hr Peak Flowrate, Qp = 12.13 cfs Rainfall Intensity at User-Defined Tc, I = 3.29 inch/'hr Peak Flowrate, Qp = 12.13 cfs 5YR EX ONSITE B.xls, Tc and PeakQ 11/07/2013, 15:54:44 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - B (10 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = B' Area = 9.90 Acres Percent Imperviousness = 45.00 % N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 10 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .73 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.44 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ Reach 2 -47- (_ Beg ^innin ( F1ow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftift ft C-5 fps minutes input input output input output output Overland 0.0150 265 0.37 N/A 0.24 18.71 1 0.0200 295 5.00 0.71 6.95 2 0.0170 260 5.00 0.65 6.65 3 4 5 . . Sum__ 820 Computed Tc = 32.31 Regional Tc = 14.56 User-Entered Tc = 14.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.60 inch/hr Peak Flowrate, Qp = 11 .22 cfs Rainfall Intensity at Regional Tc, I = 3.98 inch/hr Peak Flowrate, Qp = 17.20 cfs Rainfall Intensity at User-Defined Tc, I = 3.98 inch/'hr Peak Flowrate, Qp = 17.20 cfs 10YR EX ONSITE B.xls , Tc and PeakO 11/07/2013, 16:13:55 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - B (100 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = B' Area = 9.90 Acres Percent Imperviousness = 45.00 % N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 100 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 2.70 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.59 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND Reach 1 flow _ Reach 2 Beg ^innin ( F1ow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftift ft C-5 fps minutes input input output input output output Overland 0.0150 265 0.37 N/A 0.24 18.71 1 0.0200 295 5.00 0.71 6.95 2 0.0170 260 5.00 0.65 6.65 3 4 5 . . Sum__ 820 Computed Tc = 32.31 Regional Tc = 14.56 User-Entered Tc = 14.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 4.05 inch/hr Peak Flowrate, Qp = 23.75 cfs Rainfall Intensity at Regional Tc, I = 6.22 inch/hr Peak Flowrate, Qp = 36.42 cfs Rainfall Intensity at User-Defined Tc, I = 6.22 inch/'hr Peak Flowrate, Qp = 36.42 cfs 100YR EX ONSITE B.xls , Tc and PeakQ 11/07/2013, 16:19:17 Area-Weighting for Runoff Coefficient Calculation Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'C' (EXISTING CONDITIONS) Illustration inea stNea. _____- -f___ ---�—_— LEGEND: Flow Direction 4 t1 )%" Cat chin ent Subarea :3 Boundary Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres Coeff. A C* CA input input input output Field 3.61 45.00 I 162.49 Pavement 0. 00 100.00 0.00 Gravel 0. 19 40.00 7.57 sum: 3.80 Sum: 170.05 Area-Weighted Runoff Coefficient (sum CA/sum A) = 44.75 *See sheet "Design Info" for inperviousness-based runoff coefficient values. 5YR EX ONSITE C .xls. Weighted C 11 /07/2013, 15:56: 10 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'C' (5 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = C' Area = 3.80 Acres Percent Imperviousness = 44.75 % N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 5 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .43 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.37 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND Reach 1 flow _ Reach 2 - 'u - ' (_ Begiung ( Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0350 225 0.37 N/A 0.29 13.06 1 0.0090 225 15.00 1 .42 2.64 2 3 4 5 Sum_ 450 Computed Tc =' 15.69 Regional Tc = 12.50 User-Entered Tc = 12.50 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 3.18 inch/hr Peak Flowrate, Qp = 4.48 cfs Rainfall Intensity at Regional Tc, I = 3.53 inch/hr Peak Flowrate, Qp = 4.97 cfs Rainfall Intensity at User-Defined Tc, I = 3.53 inch/'hr Peak Flowrate, Qp = 4.97 cfs 5YR EX ONSITE C.xls. Tc and PeakQ 11/07/2013, 15:56:10 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'C' (10 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = C' Area = 3.80 Acres Percent Imperviousness = 44.75 % N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 10 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .73 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.44 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ 'u Reach 2 J (_ Begiung ( —__ Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0350 225 0.37 N/A 0.29 13.06 1 0.0090 225 15.00 1 .42 2.64 2 3 4 5 Sum_ 450 Computed Tc =' 15.69 Regional Tc = 12.50 User-Entered Tc = 12.50 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 3.84 inch/hr Peak Flowrate, Qp = 6.36 cfs Rainfall Intensity at Regional Tc, I = 4.27 inch/hr Peak Flowrate, Qp = 7.06 cfs Rainfall Intensity at User-Defined Tc, I = 4.27 inch/'hr Peak Flowrate, Qp = 7.06 cfs 10YR EX ONSITE C.xls, Tc and PeakQ 11/07/2013, 16:14:40 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'C' (100 YEAR STORM EXISTING CONDITION ) I. Catchment Hydrologic Data Catchment ID = C' Area = 3.80 Acres Percent Imperviousness = 44.75 % N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 100 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 2.70 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.59 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.37 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ 'u Reach 2 J (_ Begiung ( Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0350 225 0.37 N/A 0.29 13.06 1 0.0090 225 5.00 0.47 7.91 2 a 4 5 Sum_ 450 Computed Tc = 20.96 Regional Tc = 12.50 User-Entered Tc = 12.50 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 5.18 inch/hr Peak Flowrate, Qp = 11 .64 cfs Rainfall Intensity at Regional Tc, I = 6.66 inch/hr Peak Flowrate, Qp = 14.96 cfs Rainfall Intensity at User-Defined Tc, I = 6.66 inch/'hr Peak Flowrate, Qp = 14.96 cfs 100YR EX ONSITE C.xls, Tc and Peak() 11/07/2013, 16:19:52 PROPOSED CONDITON PROPOSED DEVELOPMENT FOR THE FUTURE RESIDENTIAL ESTATE LOT IS CONSIDERED TO CONSIST OF: House, Garage & Outbuilding to Total = 5,000 Sq. Ft. of Roof ( % Impervious = 90) Landscaped Area = 7,500 Sq. Ft. (% Impervious = 0) HARDSCAPE = 1 ,000 Sq. Ft. (% Impervious = 100) Paved Driveway = 10,000 Sq. Ft. (% Impervious = 100) Unimproved Area = Balance of Lot (% Impervious = 45) NOTE THAT NO CHANGE FROM "EXISTING CONDITIONS " IS ANTICIPATED FOR ONSITE BASINS "B " AND "C ". ONLY ONSITE BASIN "A " IS ANTICIPATED TO HAVE ANY FUTURE DEVELOPMENT THAT WOULD INCREASE THE PERCENT IMPERVIOUSNESS AND THEREFORE INCREASE RUN-OFF FROM BASIN "A " ONLY. Area-Weighting for Runoff Coefficient Calculation Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'A' (Proposed Conditions) Illustration sea. LEGEND: Flow Direction 4 ‘-'.%1‘)%" `%1r3{tom Cat chin enr Subarea :3 Boundary Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres Coeff. A C* CA input input input output Field 23.93 45.00 I 1076.92 Pavement 0.84 100.00 83.59 Gravel 0.38 40. 00 15.06 Roof 0.24 90.00 21 .85 Landscape 0. 34 0.00 0.00 Hardscape 0. 07 90.00 6.20 Sum: 25.80 Sum: 1203.62 Area-Weighted Runoff Coefficient (sum CA/sum A) = 46.65 *See sheet "Design Info" for inperviousness-based runoff coefficient values. SYR PROP ONSITE A.xls , Weighted C 11 /07/2013, 16:02:37 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - A (5 YEAR STORM PROPOSED CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 25.80 Acres Percent Imperviousness = 46.65 % N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 5 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .43 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.33 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ Reach 2 - 'u - (_ Begiung ( Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0210 400 0.33 N/A 0.31 21 .73 1 0.0210 300 15.00 2.17 2.30 2 0.0500 660 15.00 3.35 3.28 3 4 5 Sum_ 1 ,360 Computed Tc = 27.31 Regional Tc = 17.56 User-Entered Tc = 17.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.37 inch/hr Peak Flowrate, Qp = 20.25 cfs Rainfall Intensity at Regional Tc, I = 3.01 inch/hr Peak Flowrate, Qp = 25.69 cfs Rainfall Intensity at User-Defined Tc, I = 3.01 inchr'hr Peak Flowrate, Qp = 25.69 cfs 5YR PROP ONSITE A.xls , Tc and PeakQ 11/07/2013, 16:02:37 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'A' (10 YEAR STORM PROPOSED CONDITION ) I. Catchment Hydrologic Data Catchment ID = #'A' Area = 25.80 Acres Percent Imperviousness = 46.65 % N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 10 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .73 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.39 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ Reach 2 - 'u - (_ Begiung ( Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways 1St-met Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0210 400 0.33 N/A 0.31 21 .73 1 0.0210 300 15.00 2.17 2.30 2 0.0500 660 15.00 3.35 3.28 3 4 5 Sum_ 1 ,360 Computed Tc = 27.31 Regional Tc = 17.56 User-Entered Tc = 17.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.87 inch/hr Peak Flowrate, Qp = 28.74 cfs Rainfall Intensity at Regional Tc, I = 3.64 inch/hr Peak Flowrate, Qp = 36.46 cfs Rainfall Intensity at User-Defined Tc, I = 3.64 inch/'hr Peak Flowrate, Qp = 36.46 cfs 10YR PROP ONSITE A.xls . Tc and Peak() 11/07/2013, 16:16:04 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: ONSITE - 'A' (100 YEAR STORM PROP CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 25.80 Acres Percent Imperviousness = 46.65 % N RCS Soil Type = C A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 100 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 2.70 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.60 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.38 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _ - overland LEGEND ' Reach 1 flow _ Reach 2 - 'u - (_ Begiung ( Flow Direction Catchment Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0210 400 0.38 N/A 0.33 20.34 1 0.0210 300 15.00 2.17 2.30 2 0.0500 660 15.00 3.35 3.28 3 4 5 Sum_ 1 ,360 Computed Tc =' 25.92 Regional Tc = 17.56 User-Entered Tc = 17.56 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 4.61 inch/hr Peak Flowrate, Qp = 70.79 cfs Rainfall Intensity at Regional Tc, I = 5.68 inch/hr Peak Flowrate, Qp = 87.18 cfs Rainfall Intensity at User-Defined Tc, I = 5.68 inch/'hr Peak Flowrate, Qp = 87.18 cfs 100YR PROP ONSITE A.xls , Tc and PeakQ 11/07/2013, 16:21 :56 Area-Weighting for Runoff Coefficient Calculation Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE 1 -OS + ONSITE 'A' (PROPOSED CONDITION) Illustration inea LEGEND: Flow Direction 4 ``tr3{tom Carchm ent Subarea :3 Boundary Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres Coeff. A C* CA input input input output Field 33.32 45.00 1499.40 Pavement 1 . 38 100.00 138.00 Gravel 0. 59 40. 00 23.60 Roof 0.25 90.00 22. 50 Landscape 0. 34 0.00 0.00 Hardscape 0. 07 90.00 6. 30 sum: 35.95 Sum: 1689.80 Area-Weighted Runoff Coefficient (sum CA/sum A) = 47.00 *See sheet "Design Info" for inperviousness-based runoff coefficient values. 5YR PROP OFFSITE 1 -OS + ONSITE A.xls , Weighted C 11 /07/2013, 16:01 :02 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE '1 -OS' + ONSITE 'A' (5 YEAR STORM PROPOSED CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 35.95 Acres Percent Imperviousness = 47.0094D N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 5 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .43 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.33 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 (--r' (_ Beginnin^ _ —__— F1ow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.33 N/A 0.26 26.08 1 0.0120 70 15.00 1 .64 0.71 ' 2 ' 0.0040 525 15.00 0.95 9.22 ' 3 0.0110 270 15.00 1 .57 2.86 4 0.0210 700 15.00 2.17 5.37 5 0.0500 660 15.00 3.35 3.28 Sum 2,625 Computed Tc = 47.52 Regional Tc = 24.58 User-Entered Tc = 24.58 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 1 .69 inch/hr Peak Flowrate, Qp = 20.19 cfs Rainfall Intensity at Regional Tc, I = 2.52 inch/hr Peak Flowrate, Qp = 30.12 cfs Rainfall Intensity at User-Defined Tc, I = 2.52 inch/'hr Peak Flowrate, Qp = 30.12 cfs 5YR PROP OFFSITE 1 -OS + ONSITE A.xls , Tc and PeakQ 11/07/2013, 16:01 :03 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE 1 -OS + ONSITE 'A' (10 YEAR STORM PROPOSED CONDITIONS ) I. Catchment Hydrologic Data Catchment ID = A' Area = 35.95 Acres Percent Imperviousness = 47.009/0 N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 10 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 1 .73 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.39 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 (--r' (_ Beginnin^ _ -__— F1ow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.33 N/A 0.26 26.08 1 0.0120 70 15.00 1 .64 0.71 ' 2 ' 0.0040 525 15.00 0.95 9.22 ' 3 0.0110 270 15.00 1 .57 2.86 4 0.0210 700 ' 15.00 2.17 5.37 5 0.0500 660 15.00 3.35 3.28 Sum 2,625 Computed Tc = 47.52 Regional Tc = 24.58 User-Entered Tc = 24.58 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.04 inch/hr Peak Flowrate, Qp = 28.61 cfs Rainfall Intensity at Regional Tc, I = 3.04 inch/hr Peak Flowrate. Qp = 42.68 cfs Rainfall Intensity at User-Defined Tc, I = 3.04 inch/'hr Peak Flowrate, Qp = 42.68 cfs 10YR PROP OFFSITE 1-OS + ONSITE A.xls . Tc and Peak() 11/07/2013, 16:15:21 CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: NORTH COUNTRY - PUD Catchment ID: OFFSITE 1 -OS + ONSITE 'A' (100 YEAR STORM PROPOSED CONDITION ) I. Catchment Hydrologic Data Catchment ID = A' Area = 35.95 Acres Percent Imperviousness = 47.0094D N RCS Soil Type = B A, B. C, or D II. Rainfall Information I (inch/hr) = C1 " P1 /(C2 + Td)^C3 Design Storm Return Period. Tr = 100 years (input return period for design storm) C1 = 28.50 (input the value of C1 ) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1 = 2.70 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.51 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient. C-5 = 0.33 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration _- - overland LEGEND ' Reach 1 flow _ Reach 2 (--r' (_ Beginnin^ _ —__— F1ow Direction E Catchment - Reach 3 Boundary NRCS Land Heavy Tillage/ Short Neatly Grassed Paved Areas & Type Meadow Field Pasture/ Baru Swales/ Shallow Paved Swales Lawns Ground Waterways iSheet Flow/ Conveyance 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ftlft ft C-5 fps minutes input input output input output output Overland 0.0120 400 0.33 N/A 0.26 26.08 1 0.0120 70 15.00 1 .64 0.71 ' 2 ' 0.0040 525 15.00 0.95 9.22 ' 3 0.0110 270 15.00 1 .57 2.86 4 0.0210 700 ' 15.00 2.17 5.37 5 0.0500 660 15.00 3.35 3.28 Sum 2,625 Computed Tc = 47.52 Regional Tc = 24.58 User-Entered Tc = 24.58 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 3.18 inch/hr Peak Flowrate, Qp = 58.94 cfs Rainfall Intensity at Regional Tc, I = 4.75 inch/hr Peak Flowrate, Qp = 87.92 cfs Rainfall Intensity at User-Defined Tc, I = 4.75 inch/'hr Peak Flowrate, Qp = 87.92 cfs 100YR PROP OFFSITE 1 -OS + ONSITE A.xls , Tc and PeakQ 11/07/2013, 16:20:57 APPENDIX II CHARTS, GRAPHS, FIGURES & DETAILS Runoff Coefficient vs. Watershed Imperviousness Based on Runoff Coefficient estimating equation published by Urbonas. et.al. (1990) &WEF (1998) Basic equation for NRCS Soil Types C & D: Cra a Kepi'(0.858?-0.786'?+0.774'i+0.04) Basic equation for NRCS Sod Type A: Cl =1C4 +(1.311- 1.44'?+ 1.135'i•0.12) In which use values for Ca>0 in which_ i = 1/100. imperviousness ratio I. =watershed imperviousness in percent CA=Runoff Coefficient for NRCS Soil Type A K,=Correction factor for CA when the stone return period is greater than 2-years Co= Runoff Coefficient for NRCS Soil Types C and D K,a Correction factor for Co when the storm return period is greater than 2-years Values of Correction Factors Arms K4 NRCS Storm Return Petted Soil Types 2-Yr 5-n 10Ai 25-si 50-si 1(Nt-tT C&D 0.00 I-0.I0en0.Ill I-n IS•r+0211 I-02S•r-o ≥1 I-n ;:•,.iitut l.ri )9•:-ri u' A 0,00 f-o.oa•r+o( il l.o.t.t•r+o.I l 1-C' 19',-') :11 1-022•,-i,1st i-o2c•,-i, .CI Values of RuuotI (oetltctcul co Values of Runoff Coefficient C, Wipers.. I we C and D NRCS tivdxologic Soil (stoups I vpc.t NRCS Hydrologic Soils Group Ratio( I) 2-\T 5-\T I OAT 25-st 50-vi 1(N)-sr 2-ST 5-vr 10-n 25-vt 50-ST IOU-sT 0.00 0.84 0.15 0.25 0.37 0.44 0.53 -0.12 -0.b3 0.05 ' 0.12 0.A 028 0.05 0.08 0.18 0.28 0.39 0.46 0.52 -0.07 0.02 0.10 0.16 0.20 0.24 0.10 0.11 0.21 0.30 0.41 0.48 0.53 -0.02 0.06 0.14 0.20 0.24 0.28 0.15 0.14 0.24 0.32 0.43 0.49 0.54 0.02 0.10 0.17 0.23 0.27 0.30 0.20 0.17 0.26 0.34 0.44 0.50 0.55 0.06 0.13 0.20 0.26 0.30 0.33 0.25 0.20 0.28 0.36 0.46 0.52 0.56 0.09 0.16 0.23 0.29 0.32 0.35 0.30 0.22 0.30 0.38 0.47 0.53 0.57 0.13 0.19 0.25 0.31 0.34 0.37 0.35 0.25 0.33 0.40 0.48 0.54 0.57 0.16 0.22 0.28 0.33 0.36 0.39 0.40 028 0.35 0.42 0.50 0.55 0.58 0.19 0.25 0.30 0.35 0.38 0.41 0.45 0.31 0.37 0.44 0.51 0.56 0.59 0.22 0.27 0.33 0.37 0.40 0.43 0.50 0.34 0.40 0.46 0.53 0.57 0.60 0.25 0.30 0.35 0.40 0.42 0.45 0.55 0.37 0.43 0.48 0.55 0.59 0.62 0.29 0.33 0.38 0.42 0.45 0.47 0.60 0.41 0.46 0.51 0.57 0.61 0.63 0.33 0.37 0.41 0.45 0.47 0.50 0.65 0.45 0.49 0.54 0.59 0.63 0.65 0.37 0.41 0.45 0.49 0.51 0.53 0.70 0.49 0.53 0.57 0.62 0.66 0.68 0.42 0.45 0.49 0.53 0.54 0.56 0.75 0.54 0.58 0.62 0.66 0.69 0.71 0.47 0.50 0.54 0.57 0.59 0.61 0.80 0.60 0.63 0.66 0.70 0.73 0.74 0.54 0.56 0.60 0.63 0.64 0.66 0.85 0.66 0.68 0.71 0.75 0.78 0.79 0.61 0.63 0.66 0.69 0.70 0/2 0.90 0.73 0.75 0.77 0.80 0.83 0.83 0.69 0.71 0.73 0.76 0.77 0.79 0.95 0.80 0.82 0.84 0.87 0.89 0.89 0.78 0.80 0.82 0.84 0.85 0.86 1.00 0.89 0.90 0.92 0.94 0.96 0.96 0.89 0.90 0.92 0.94 0.95 0.96 Notes: For Type B Soils. use the avetage of coefficients Co and CA. When the Runoff Coefficient in above table is<0. use 0. When coinpositing the Runoff Coefficient for different soil types.use the table values above regardless if they are< 0. Runoff Coefficient vs. Imperviousness Runoff Coefficient vs. Imperviousness NRCS Hydrologic Soils C & D NRCS Hydrologic Soil A 1.00 1.00 • • 0.90 A 0.90 +Column G 0.80 0.80 +Column E +Column M c 0.70 +Column D c 0.70 +Column K g 0.60 r/ ;Column B e 0.60 +Column J air Column I 8 0.50 8 0.50 -Column H It 0.40 t 0.40 c 0.30 3 0.30 it 0.20 m 0.20 0.10 0.10 0.00 0.00 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 Watershed Impervious Ratio Watershed Impervious Ratio Page 4 I. One-hr Precipitation Values for Metro Denver Area Return period in years 2 5 10 50 100 Depth in inches 0.93 1 35 1 .61 2.20 2.60 II. Recommended Runoff Coefficients for Metro Denver Land Use or Surface Characteristics Percent Imper- viousness Business: Commercial areas 95 Neighborhood areas 85 Residential: Single-family Multiunit (detached) 60 Multiunit (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: Historical Flow Analysis 2 Greenbelts, agricultural Off-site flow analysis 45 (when land use not defined) Streets: Paved 100 Gravel (packed) 40 Driveways and sidewalks: 90 Roofs: 90 Lawns. sandy soil 0 Lawns. clayey soil 0 *Refer to Figures RO-3 through RO-5 in Runoff Chapter of USDCM . Page 5 List of Variables A = watershed area in acres C = runoff coefficient C1 , C2, and C3 = coefficients in IDF formula 05 = 5-yr runoff coefficient I = rainfall intensity in inches/hour ID = user defined identification number L = flow length in ft S = slope for flow length in ft/ft P1 = one hour precipitation value in inches Tc = time of concentration in minutes Td = design rainfall duration in minutes Tf = flow time in minutes Tr = return period in years Qp = peak runoff rate in cfs V = flow velocity in ft/second 5YR PROP ONSITE A.xls, Notation 11 /07/2013, 16:02:39 Hello