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Home My WebLink About03540 - Technical Information Report - Drainage � a , (. c'iij#t[`! �i,iM ii►ia�ij. qiii • Sur.�e�c�rs eP��[liiet'S •EF�•��..�6:<. ; - 1 � h � STORM DRAINAGE NARRATIVE � OF QUI FENG LI 1515 LAKE AVE S RENTON, WA FOR �..��.�� .,a �,�.r'��',� RAYMOND NG � � � �� .��, t.�" f' r—,,��{.s,g''.:ti.. ��j��' /�.�: ^r, �s-� 6622 S. 124 ST. ��'`�� 6x��.• - _ �" j � �. �':.a,,,.. .a SEATTLE, WA 98178 �, . ' .. - �;�� `.�� ;`:=a �� .� ? �, a "�'�` �- .�► ��pF�I�i€�'�' .:ti�:�,�f ��';�,�►L ��- July 28, 2008 (REVISED 11-19-49) ----� z__ - �j-(`�'-G� C.N.I. JOB NO. 2007-074 Prepared by Larry S. Krueger, P.E. _ _ .. _. 'ut. �1'!.�.. " , i�> l�t .. ^_ '_ _ ,i;�rti?_1XYfi l=�� f?i?1 X�?_��1�5 �r3 5s�b . � � i. PI�C�J�CT QVERVIEW �I Existing Conditions: This project is located at 1515 Lake Av�� S. in the City of Renton. The site is approximately 0.34 acres. There is an existing home located in the eastern portion of the property. There is an exi:sting shed in the western portion of the property. There is also a concrete drivE�way, and there are some concrete and brick walkways. The rest of the site is rnostly grass in the eastern finro thirds of the site, while the western third consist;> of mostly trees and brush, with a steep slope that slopes to the west. The exisl ing site drainage sheetflows to the west toward a wetland and SR 167. The site's soils appear to be a combination of Beausite Gravelly Gravelly Sandy Loam, 6 to 15 percent slopes (BeC), Beausite I Gravelly Gravelly Sandy Loam, 15 to 3()5 percent slopes (BeD), and Puget Silty Clay Loam (Pu). i Proposed Conditions: I The project proposes to subdivide the site into two residential lots. Both lots will I access off of Lake Ave South via a new 15' wide paved driveway. New roof runoff will be conveyed through a downspout dispersion trench and the new driveway runoff will be controlled via another dispersion trench, II. REQUIREMENTS SUMMARY The core requirements of the King Courity Surface Water Design Manual (KCSWDM) will be provided as follows: Core Requirement #1, Discharge at the Natural Location: The natural discharge location fo�this site is along the west property line where the runoff enters a wetlancl located along the east side of SR 167. This will remain the discharge location of the new roof and driveway runoff after it is routed through diapersion trenches. Core Requirement #2, Offsite Analysi�: Please see Level 1 Offsite Drain��ge Analysis in Appendix B. Core Requirement #3, Runoff Control; Runoff will be controlled via dispe�rsion. ,, , Core Requirement#4, Conveyance System: There is a new conveyance syst�m for the new driveway that consists of storm pipes and catch basins. Core Requirement #5, Erosion/Sedirr�entation Control: An erosion and sedimentation ccmtrol plan will be implemented during construction. Some of the elemE�nts that are anticipated to be included are a construetion entrance, silt rence, and seeding. Core Requirement #6, Maintenance and Operations: A maintenance and operations r��anual will be submitted at a later date, if requested. Core Requirement #7, Financial Guarantees and Liability: The owner will provide this inforr�ation prior to permit issuance. III. OFFSITE ANALYSIS Please see Appendix B for offsite analysis. IV. RETENTION/DETENTION ANAL.YSIS AND DESIGN Flow control is not required for this site because the improvements do not increase the existing runoff by 0.5 cfs or- greater. Per Section 1.2.3 of the 1990 KCSWDM this project is exempt from runoff control. Calculations are provided in Appendix A. 1�. CONVEYANC� SY�TEM ANAL`f�l$ AND DE�IGN There is a new conveyance system for the new driveway that consists of storm I�, pipes and catch basins. Calculations w ll be provided at a later date if � requested. VI. SPECIAL REPORTS AND STUD�IES A Geotechnical Report has been prepared by PanGEO Inc. for this project. VII. BASIN AND COMMUNITY PLANS No basin or community plans are known to exist. VIII. QTHER QERMIT� No other permits are known to be requir��d at this time. 4 ' IX. EROSIONISEDIMENTATION C��NTROL DESIGN An erosion and sedimentation control plan will be implemented during construction. Some of the elements th��t are anticipated to be included are a construction entrance, silt fence, and sE:eding. Calculations will be submitted at a later date, if required. X. BOND QUANTITIES, FACILITY SUMMARIES AND DECLARATION OF COVENANT This information will be provided prior t�� permit issuance if requested. XI. MAINTENANCE AND OPERATFONS MANUAL A maintenance and operations manual �rill be submitted at a later date, if requested. I i I APPENDIX A � FLOW CONTRO� CALCULATIONS i f � RUNOFF CALCULATIONS PERFORII�ED BY STORMSHED Project Precips [10o yr) 9.80 in Drainage Area: predev Hyd Method: SBUH Hyd Loss Method: SCS CN Number Peak Factor. 484.00 SCS Abs: 0.20 Storm Dur 24.Od hrs Area CN TC Pervious 0.2600 ac 83.62 0.20 hrs Impervious 0.0800 ac 98.00 0.00 hrs , Total 0.3400 ac Supporting Data: Pervious CN Data: pasture 85.00 0.1700 ac trees, brush and grass 81.00 0.0900 ac Impervious CN Data: buildings, driveways,walks 98.00 0.0800 ac Pervious TC Data: Flow type: Description: Length: Slope: CoefF: Travel Time Sheet grass 159.00 ft 15.00% 0.1500 7.83 min Sheet brush, trees, long grass 17.00 ft 65.00% 0.4000 1.60 min Sheet brush, trees, long grass 30.00 ft 55.00% 0.4000 2.69 min Impervious TC Data: Flow type: Description: Length: Slope: Coeff: Travel Time Sheet dummy variable 1.00 ft 70.00°� 0.0100 0.01 min Drainage Area: dev Hyd Method: SBUH Hyd Loss Method: SCS CN Number Peak Factor: 484.00 SCS Abs: 0.20 Storm Dur 24.00 hrs Area CN TC Pervious 0.2300 ac 84.04 020 hrs Impervious 0.1100 ac 98.00 0.00 hrs Total 0.3400 ac Supporting Data: Pervious CN Data: lawn 86.00 Q.1400 ac trees, brush and grass 81.00 0.0900 ac Impervious CN Data: buildings, driveways, walks 98.00 0.1100 ac Pervious TC Data: Flow type: Description: Length: Slope: Coeff: Travel Time Sheet grass 159.00 ft 15.00% 0.1500 7.83 min Sheet brush, trees, long grass 17.00 ft 65.00°k 0.4000 1.60 min Sheet brush, trees, long grass 30.00 ft 55.00% 0.4000 2.69 min Impervious TC Data: Flow type: Description: Length: Slope: Coeff: Travel Time Sheet dummy variable 1.00 ft 70.00% 0.0100 0.01 min BasinlD Peak Q Peak T Pe�ik Vol Area Method Raintype Event ------- (cfs) (hrs) (ac��ft) ac /Loss predev 0.6471 8.00 0.2324 0.34 SBUHISCS TYPEIA 100 yr dev 0.6643 8.00 0.2379 0.34 SBUH/SCS TYPEIA 100 yr APPENDIX B OFFSITE ANALYSIS LEVEL 1 QR.AINAGE ANALY�I� OF QUI FENG LI SHORT PLAT 1515 LAKE AVE S RENTON, WASHINGTON FOR RAYMOND NG 6622 S. 12��ST. SEATTLE, WA 98178 I November 19, 2009 C.N.I. JOB NO. 2007-074 Prepared by Larry S. Krueger, P.E. TABLE OF CONTENTS I. TASK1 STUDY AREA DEF�INITION AND MAPS ' II. TASK 2 RESOURCE REVIE:W II' III. TASK 3 FIELD INSPECTION IV. TASK 4 DRAINAGE SYSTE:M DESCRIPTION AND PROBLEM DESCRIPTIONS V. TASK 5 MITIGATION OF E;�CISTING OR POTENTIAL PROBLEMS TASK1 STUDY AREA I�EFINITION AND MAPS � �, _ _ _ TASK 1 STUDY AREA pEFINITIQN This project is located at 1515 Lake Av�� S. in the City of Renton. The site is approximately 0.34 acres. There is an �xisting home located in the eastern portion of the property. There is an exi:�ting shed in the western portion of the property. There is also a concrete driveway, and there are some concrete and brick walkways. The rest of the site is rnostly grass in the eastem two thirds of the site, while the western third consist;> of mostly trees and brush, with a steep slope that slopes to the west. The exisi ing site drainage sheetflows to the west toward a wetland and SR 167. The site's soils appear to be a combination of Beausite Gravelly Sandy Loam, 6 to 15 percent slopes (BeC), Beausite Gravelly Sandy Loam, 15 to 30 percent slopes (BeD), and Puget Silty Clay Loam (Pu). MAP� A vicinity map, sensitive areas map, aerial, and offsite drainage map can be found in the proceeding pages. VICIPJITY MAP � � � < � .�.VJ AY Z S�� d _ z .SV��`��NY � �1�►'''� r. � � SRHiTONV11At�0. � < _ � � .. � m � � ,,�� ; '=:� '�1 y� Y�:. — _ �'--�_,..- '_�::�,�`'� : - 5��H5t - ��-,"�"_:�"F'" .------�-��---�-s'_' � _ _- - ` -_ __ .-��.-�_=. � '� `� _ __�-- , _ { , �, � w q - . r �) � � y � y¢y� � � S �y; a.� E.� . .. � � � f� �-,.�,_ . �i � �'`r � � �:_:� .+ �� ;; SiSMST SYt' '�t M Sl L�� t (� �� Si�eet Par�r ' �- t ; ,� �:enton ; �a � � S t6TN ST � � � aa O � T '� S�7Th 5T � � � � J Q J 1� ' S � m � � S tBTH 5T 6 y SW 14TH ST S t9TN ST S 19Tk ST ','1 iower TaA�ot HNY Park '�16at HiBi ResrrYoirParh S 20iM Pt S 2�li pi � U �, �y SZ•.ST t� �'- �' � � � < S?2Np p� � � � �Ci��ingCaunty D 5T21� S23�CST The idomelion induded on Utis r�p t�s been compileU by IGr�Couily st�t irom a vaneFy d sources and's 5ubjeG to change wRfq�d nOtite.Kng County makes ro represeNauatis a warrmities.expc�as or imq�ed.as 10 acaracy.mmpet�.t6neia�ess.or rgMs to lhe use d s�ch i�dortnation. This doa,men s not ui[ended fw�se as a survey pioEuci Ne� Counly�1 not be tiable Tor s^Y 9e�a1.spedal.iidvecL incderdal,�m�ential a ��o�� a�. ��u,e��aa,m�sm�.ay��r KingCounty Date:1 U18/l009 Sarce:Kag Couriy iMAP-Pioperty tdorrtation(ht�tlwww.metmkc.�iMAP) i� • � 1 � `, f� X ,� • e1 �a� �!t� � ' C7 � . � '-�e ,�I� I '� � �i � �� , ' � � Vi � R 4� ��y:1 � 3 � ��', . . � '�f t�� `� I � � � °� ,, p�E� �� _ � � .,,. � , �: r.„ , � ��;. . ,K r hr �� ,'� .e cl� � r�Xr��w �w''� E� � � �� ' � , �. �_ �,�,,,,..,_----'---._ ,�.�,�� ,��"� �r�� a,�� '� � �� "' �� a �; i'� �. � . 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I � � � ��. h : ��fr �' + „t i ..� �� ,�� . . r, �<t� ,'+�-� .wr � }' � -,�.,, f . ,r .:•: � .� �1. ; � ��'. . ��.y . ' • , . . - .. . ..:.: 'Y F w.�.r�� : �S � „, : � i . 'i. :�.;.�.. � - f �' � 1 M '� ( 1 ; � f . , r �' 4 ,'� j � ��,��.;��1 -; ;�, d �` r �-`,' °.� �. � ��,,,�.+ x�� ,�'" � � � � �� ,�.,��.� ^�M�s.t�L,• ��+;. �i t Y�4.�,a�t!u_ . . .. � � �� r � T�o- . . � � �.�� a `� t .��.��w. �� M� � .rYYi° M�.n�Yr r��r 1 t �� ,1� � � M 6� � � � .'C� � ,�,� je�� ^! i� ,��, .� i-�.,y� q `� � yw�e,�,.�. .... , . ,'" . t7 1: '� dr�r r1� r. ,��}f�'.!F' " -- -i ` +l�Fc:,-.Mii� �.� IL � Y _.... _ ��K�� ' - - ` ,:Y ',�� . � �t�.ltS� �.� �� 3� 1 a' �i� /p � _ ■ � L V :i . . �3 i.R 1� lyy�ry i ■ ��k � F � f ; . + � ,. . � i7fr , y{, e ; I' �t ��'�• �"H�"�' � �. . 4. � ��Wn f � �S � :. � ,p � . .:' ,. � � q4R M�Y ... � �r'I��i � . :� ��T ) ', 4 �' ' d � r ' � — ,� ��y � ��`� �a.'r :t �S� ;K?}�,�. ;� . � ' � :r � y�a , A � � 1�� - ��s �. �� ,��`�� . '�. riMl �a�� " � ,� � �/ � 'i.'" . � t . i �� . f I, -.� t i1. y _1 .. > > > . ,� �, � ' '�;r � r:i � . ' i � � � � L1J � W � W U � � O � w � I N Y � Q � TASK 2 RESOURCE REVIEW Adopted Basin Plans and Finalized Drainage Studies: The site is not located in a basin plan. Basin Reconnaissance Summary Re��orts: No known reports are known to exist. Critical Drainage Area Maps: The site is not known to be located in any critical drainage areas. (FEMA) Maps: The site is located outside the 100 year flood plain. Other Offsite Analysis Reports: No other downstream analysis reports are known to exist. Sensitive Areas F��li� None of the site is loc map under Task 1). However, there is �� wetland west or tr,e sita ana tr�e 10G year floodplain is located to the south o1 the site DNR Drainage Problems Maps: Not applicable. Road Drainage Problems: Not applicable. King County Soils Survey: � The site's soils appear to be a combinat on of Beausite Gravelly Sandy Loam, 6 to 15 percent slopes (BeC), Beausite (;ravelly Sandy Loam, 15 to 30 percent slopes (BeD}, and Puget Silty Clay Loam (Pu). Wetlands Inventory Maps: There is a category 2 wetland located w��st of the site. The wetland's buffer is located in the western portion of the site. Migrating River Studies: Not applicable. Drainage Complaints: According to the drainage complaints prc�vided by King County on IMAP, there were no complaints near the downstream analysis limits of this project Z O � U W � � Z r, u � W LL M � � Q H TASK 3 FIELD INSPECTION A field inspection was conducted on Nc►vember 4, 2009 to inspect the onsite drainage system of the site. Offsite dr2inage systems were also inspected I, downstream approximately 1/4 mile{s) from the discharge point of the site. The I inspection involved investigation of the ten specific items of a Level 1 I Inspection per the King County Surtace Water Design Manual, 1990. The � inspection yielded the following finding>: ' 1. There were no existing or potential F�roblems observed. 2. The existing drainage system capacty was adequate. 3. There were no existing or potential ffooding problems. 4. There were no existing/potential overtopping, sedimentation, scouring or bank sloughing problems. 5. No significant destruction of aquatic habitat or organisms was noticeable. 6. Qualitative data such as land use, impervious surfaces, topography, and ' soil types was noted and can be found in Task 4 information. 7. Information was collected on pipes, ditches, and structures. This I information is also included in the T��sk 4 information. 8. Tributary basins delineated in Task ' were verified. 9. No neighbors were contacted. 10. The weather conditions at the time c�f the inspection were windy and rainy. TASK 4 DRAINAGE SYS�TEM DESCRIPTION AND ' PROBLEM DE:SCRIPTIONS i ; TASK 4 DRAINAGE SYSTEM DESCF:IPTION AND PROBLEM I DESCRIPTIQNS Site Drainaqe i This project is located at 1515 Lake Av�: S. in the City of Renton. The site is � approximately 0.34 acres. There is an �xisting home located in the eastern ! portion of the property. There is an exi:�ting shed in the western portion of the property. There is also a concrete drivE�way, and there are some concrete and brick walkways. The rest of the site is rnostly grass in the eastern two thirds of the site, while the western third consist:� of mostly trees and brush, with a steep slope that slopes to the west. The existing site drainage sheetflows to the west toward a wetland and SR 167. The site's soils appear to be a combination of Beausite Gravelly Sandy Loam, 6 to 15 percent slopes (BeC), Beausite Gravelly Sandy Loam, 15 to 30 percent slopes (BeD), and Puget Silty Clay ' Loam (Pu). Offsite Drainaqe An Off-Site Analysis Drainage System T�able is provided on the next page that describes in detail the offsite drainage components at least %4 mile downstream i from the project discharge location. Please refer to the offsite drainage map in _ Task 1 because the map symbols listed in the table correspond to drainage component symbols on the offsite drain��ge maps. � _ _ � OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE SURFACE WATER DESIGN MANUAL, CORE REQUIREMENT#2 Basin: Black River Subbasin Name: Subbasin Number: Symbol Drainage Drainage Slope Distance Existing Potential Observations of fieid Component Type, Component from site Problems Problems inspector, resource Name, and Size Description discharge reviewer, or resident See map Type:sheet flow,swale, drainage basin,vegetatlon, % '/.ml= 1,32D ft. constrictions,under capacfty,ponding, tributary area,likelihood of problem, stream,channet,pipe, cover,depth,type of sensitive overtopping,floodfng,habitat or organism overtlow pathways,potentlal impacts pond;Size:diameter, area,volume destruction,scouring,bank sloughing, ' surtace area sedimentation,incision,other erosion A Sheet Flow Leaves site on thc west �1% 0-�130'0' None None None side into a wetland. Wctland is heavily vegetated with grass and trees. B Swale Runoffenters large �1% 130'--�630' Nnnr NnnP e;;,�� h��n.�a �- �- :,.,�,,.........:,.., �usy swale (---6-8')along east freeway. No problems side of SR 167 and observed. flows south. Swa1e is vegetated with grass, trees, and bcrry vines. C 3'xY box culvert Runoff enters box -1% 630'-�900' Nonc None Culvert wasn't observed due culvert that flows west to busy freeway and lockcd under SR 167. lids. D 5'pipe and manholes Flows south along west 0.15% 900'-�1500' Nonc None None sidc of East Valley Road. S into a concrete pipe ys-a��nBoa E 5' pipe and manholes Flows west under the 0.l_5% 1500'-3900' None None None. southern lane of SW 19�' Strcet. F Swale Runoff dumps into �I% 3900'+ None None None. large swale(�]0' wide) west of the intersection of SW 19�' Street and Raymond Ave SW and continues to flow west. Swale had dirt bottom, 1-2' of water in it,trees and brush on the sides. 98-4\inB04 TASK 5 MITIGATIC)N OF EXISTING OR POTENTIAL PROBLEMS , TASK 5 MITIGATION OF EXISTING C)R POTENTIAL PROBLEMS After a thorough field inspection and a ��etailed resource review there were no major or existing problems identified. 1�he proposed improvements will not produce a significant impact to the existing drainage patterns once the site has been stabilized and the runoff has beeri controlled via dispersion trenches. A temporary erosion and sedimentation control plan has been designed to minimize the transport of sediment laden runoff to the downstream conveyance system prior to permit issuance. . a � (_��'��t3i' ��•tl��r��i, Ii�4:, • Surveyars �Ptafinei�s •Enginee�-s November 19, 2009 Rick Moreno, Engineering Specialist City of Renton Development Sen�ices Divisian 1055 S. Gradv Wa�- Renton,WA 98057 RE: Qui Feng Li Short Plat(LUA08-148) Dear Mr. Moreno: We have received your comments da.ted October 23,2009 regarding the above project. We have addressed those comments below. 1. We have revised the drainage narrative to include an offsite analysis. Please see AppendiY B of the narrative for the Level 1 Offsite Analvsis. 2. We have provided drainage calculations in Appendix A of the narrative that sho«�that the project is '� exempt from flow control because the improvements do not increase the existing runoff by 0.5 cfs or greater. The drainage calculations show that the ne�ti�improvements only increase the runoff by less than 0.02 cfs,«hieh is well belo��the threshold. �� We feel that��e have adequately addressed�-our comments. Please approve this project as soon as��ou II can. � Sincerely, � - J ��- -,, _.;y�� v�� Larry . I�-ue.ger. P.E. � C ramer'.�]�t (LJ�)bJl--F�aU l d�(ljj)�JL-�yJJ ��v.cramern�r.ce��i F.-mail: c��+�%�':cran?crn«.co?r, , De�i�aw Cl�Of, ,� ' o E' : ,�, - �1 � � ,` � �� ; � . �� . ' ��o Depactment of Lommunity and Economic Development Alex Pietsch,Administrator October 23, 2009 Larry 5. Krueger, P.E. 945 North Central,Suite#104 Kent,WA 98032 SUBJECT: QUI FENG LI SHORT PLAT LUA-08-148 CIVIL PLAN REVIEW Dear Mr. Krueger: We have completed our review of civil improvement pians submitted on October 22, 2009. The review included the civil design issues including starm water,sanitary sewer, and domestic water utility improvements necessary to develop the site. Please refer to the red line plans attached for eomplete correction remarks and comments. For items referencing the Storm Water Comments, please respond as identified below: 1. Under the conditions o#the Surface Water Narrative received December 16, 2008, a complete offsite analysis will be submitted during the engineering review stage of this project. To dote, no offsite analysis has been received. 2. Previous plan review for this project requested the engineer support by calculation,the assumption the proposed runoff will not exceed 0.5 cfs. To dore, no calculations hove been received to support this requesi. Please provide two (2)sets calculations which support the civil ptans. If you have any '� questians, please contatt me at (425}430-7278 or rmoreno rentonwa.(�o�. ��, Sincerety, � Rick Mor�no , Engineering Specialist , aevelopment Services Division/Plan Review attachments i Cc: Kayren Kittrick,Development Fngineering Supervisor RM 09-045 Renton City Hall • 1 Q55 5outh Grady Way • Rertton,Washi�gton 98057 • rentonwa.gov � � � Cramer Northwest. Inc • Surveyors •Planners •Engi�neers �r�E�P��c'=}y 1`' ;•t STORM DRAINAGE NARRATIVE ��-�c�r�``� d � '��i� ' D�� ,��c`� . (�� 1515 LAKE AVE S RENTON, WA ��G��"�� FOR �� C �� c� RAYMOND NG 6622 S. 124 ST. � SEATTLE, WA 98178 � �� n �tis�� '�,>,i;�,�� v�J r 7�^. ��iy 2s, 2oos � � _�.�-�--� C.N.1. JOB NO. 2007-074 Prepared by Larry S. Krueger, P.E. 945 N. Centrai.Suite#104 Kent WA 98032 (2��)852-4880 Fax(253)852-�955 «��v.cramernn.com E-maiI: cnira-cramern�i.com f � 1. PROJECT OVERVIEW Existing Conditions: This project is located at 1515 Lake Ave S. in the City of Renton. The site is approximately 0.34 acres. There is an existing home located in the eastern portion of the property. There is an e;<isting shed in the western portion of the property. There is also a concrete driveway, and there are some concrete and brick walkways. The rest of the site is mostly grass in the eastern two thirds of the site, while the westem third consi:;ts of mostly trees and brush, with a steep slope that slopes to the west. The existing site drainage sheetflows to the west toward a wetland and SR 167. The sii:e's soils appear to be a combination of Beausite Gravelly Gravelly Sandy Loam, 6 to 15 percent slopes (BeC), Beausite Gravelly Gravelly Sandy Loam, 15 to :305 percent slopes (BeD), and Puget Silty Clay Loam (Pu). Proposed Conditions: The project proposes to subdivide the site into finro residential lots. Both lots will access off of Lake Ave South via a ne�ti 15' wide paved driveway. , New roof runoff will be conveyed through a downspout dispersion trench and the I new driveway runoff will be controlled �via another dispersion trench. II. REQUIREMENTS SUMMARY The core requirements of the King County Surface Water Design Manual (KCSWDM) will be provided as follows: Core Requirement#1, Discharge at the Natural Location: The natural discharge location f��r this site is along the west property line where the runoff enters a wetland located along the east side of SR 167. This will remain the discharge location of the new roof and driveway runoff after it is routed through dispersion trenches. Core Requirement#2, Offsite Analysis: A complete offsite analysis will b�e submitted during the engineering review stage of this project, if recauired. The existing site drainage sheetflows to the west toward a�nretland on the east side of SR 167. . � Core Requirement #3, Runoff Control: Runoff will be controlied via di:>persion. Core Requirement #4, Conveyance System: There is a new conveyance sy:stem for the new driveway that consists of storm pipes and catch basins. Core Requirement #5, Erosion/Sedimentation Control: An erosion and sedimentation c;ontrol plan will be implemented during construction. Some of the elements that are anticipated to be included are a construction entrance, silt fence, and seeding. Core Requirement#6, Maintenance and Operations: A maintenance and operations manua( will be submitted at a later date, if requested. Core Requirement #7, Financial Gu�irantees and Liability: The owner will provide this information prior to permit issuance. 111. OFFSITE ANALYSIS ��+plete�#sitea�lysis � , _:.�-- �.��_ .. . . _. _ The existinc� site drainage sheetflows to the west � toward a wetland on the east side of SR 167. IV. RETENTI�N/DETENTION ANA,LYSIS AND DESIGN Flow control is not required for this sitE� because the improvements do not increase the existing runoff by 0.5 cfs or greater. Per Section 1.2.3 of the 1990 KCSWDM this project is exempt from runoff control. Calculations will be provided if requested. V. CONVEYA6NCE SYSTEM ANAL,YSIS AND DESIGN There is a new conveyance system for the new drivewa� that consists of storm pipes and catch basins. ��lcutations v!rill be� � � .. VI. SPECIAL REPORTS AND STUI)IES A Geotechnical Report has been prepared by PanGEO Inc. for this project. VII. BASIN ANC► COMMUNITY PLA�JS No basin or community plans are known to exist. VIII. OTHER PERMITS No other permits are known to be required at this time. IX. EROSION/SEDIMENTATION �;ONTROL DESIGN An erosion and sedimentation control plan will be implemented during construction. Some of the elements tl�at are anticipated to be included are a construction entrance, silt fence, and seeding. Calculations will be submitted at a later date, if required. X. BOND QUANTITIES, FACILITI( SUMMARIES AND DECLARATION OF COVENANT This information will be provided prior to permit issuance if requested. XI. MAINTENANCE AND OPERAI'IONS MANUAL A maintenance and operations manual will be submitted at a later date, if I requested.