Loading...
HomeMy WebLinkAbout03631 - Technical Information Report �. . , t. � ncampass ENGINEERING S SURVEYING / � M � � \ TECHNICAL [NFORMATION REPORT � fo r �� � � Sarah's Short Plat � January 11, 2012 �.Ev1s�0 3/2���z_ ````��\\\\��� *� 1 s� `�IY���' �,+l/ + � � i Q'�:< - , r��: �� ��I ,, i�=�'�\ - �'`'` % %� ,� _ '- � i f ,-.�,_,_�-. C ,I �.�` ��"� , . �'�Q� 1 F . . ,"-"`-`;�`��— , r , , � � ������`�NALiN��� �'�� i .f ;' ''i' ����� Encompass F;ngineering Job No. 11627 Prepared For Bill Hughc� 14401 Issaquah-Hobarz Issaquah, WA 9802 Western Washington Division Eastern Washington Division 165 NE Juniper St., Ste 201, Issaquah, WA 98027 108 East 2"d Street,Cle Elum, WA 98922 Phone: (425)392-0250 Fax:(425)391-3055 Phone: (509)674-7433 Fax: (509)674-7419 www.EncompassES.net 3�3� � A . . TABLE OF CONTENTS SECTION TITLE 1 PROJECT OVERV�W 2 CONDITIONS AND REQUIREMENTS SLTMMARY 3 OFFSTTE ANALYSIS 4 FLOW CONTROL AND `VA'ITER QUALI'TY FACILITI' ANALYSIS AND DESIGN 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN 6 SPECIAL REPORTS AND ST`CIDIES 7 OTHER PERMITS 8 ESC ANALYSIS AND DESIGN 9 BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT 10 OPERATIONS AND MAINTENANCE MANUAL � �� SECTION 1 PROJECT OVERVIEW I I _ . � � � Site Address: 2416 Edmonds Av� NE King County Tax Parcel: 042305-9138 Project Overview This project involves the development of a 0.78-acre parcel into five single-family residential lots. The site is currently occupied by a single family residence with a concrete driveway and a couple of sheds. The remainder of the site is generally covered with poorly-maintained lawn with a few trees. The site generally slopes down to the west at about 1%. Per the SCS soils map, the site is underlain with Indianola soil: topsoil over a fevv feet of sand. Upstream Drainage Basin Little if any offsite areas drain onto the site. Level 1 Downstream Drainage Analysis Because the site is very flat and is underlain with sandy soil, it is expected that the majority of rainfall onto the site infiltrates into the soil. What water doesn't infiltrate would drain west, probably flowing across the Edmonds Avenue NE sidewalk and into gutter (A). The gutter drains north at about 2%about 150' where flows enter the public storm system through a catch basin grate located at the southeast corner of intersection of Edmonds Avenue NE/NE 25ih Street (B). A 6" storm pipe connects this catch basin to an 18" storm conveyance pipe located in the Edmonds Avenue NE paving, towards the west side of the street (C). This 18" concrete pipe continues north about another 250' where it enters another catch basin located about 30' north of where Edmonds Avenue NE ends at NE 27th Street (D). From here a 24" pipe exits the catch basin, outfalling about 600' cross-slope down a very steep slope overlooking Honey Creek (E). This pipe discharges into what looks like a deep stilling basin at the toe of the steep slope (F), with another 24" pipe exiting at the bottom (G). This pipe discharges onto a concrete apron, where there is substantial erosion. Flows go towards Honey Creek though a deep, moderately eroded but stable, flat gradient channel (H), to beyond '/4 mile downstream from the site. Other than the aforementioned erosion, the downstream drainageway doesn't appear to have any serious problems. Proposed Drainage Control Because the site is underlain with sandy soil, all roof, driveways and roadway surfaces will be infiltrated, eliminating the need for a stormwater detention system. Full Infiltration trenches �i�ill I�, provide the required flow control and BMP's for the paved driveway surface—individual dry wells will provide full infiltration for the roofs. A filter strip along the common driveway will provide the required water quality mitigation for the pollution-generation paved surface. _ � � II a = � i � . . . i � ._ � ' � ._ . , __�=2 , � \ / Fd110 J/�• ��'L Rt A1 VR _. � al!'E __ N 88'15'15" W 34 .49' � � I °` 70.01' 80.02' � _--- �7r�� 62.5 � 50.21' � �,... ��..,T7T/m�..,� � �_ �j1'�-- 1 � O GMIA�F E_ W I �p � � 'roonHc O ii n' _... 1 7, Ot Sq �t�^�^� 2 � rr-azz is o_ �, � q w 8,0 2 7,773 Sq Ft � 1 � 5 � S ;�� N (5, 0 Sq Ft) ��, 10, (5,741 Sq Ft) W 6,251 Sq Ft w 5,021 Sq t � Z - • o . 20 1 o N (5.001 Sq Ft) � N . �� k��r�N��o�u 1 � � � I M •� . ��_ie�en ^' J �i M O � r / W �\ o o �z,a s� g Z LJ,J :� / � \ � � • � � -� � > o -- — -- �� � � � Z . Z Q z — _ . �„ ,,, � o . i ,�� .. . , ' � " --Jla `��� .. . , � � �� � ' � ' . . , • � - ' . �� � ' . . �� 6„ /� `.� Q ' _— 7� ' . . e.. �r v' x' ��," .. :. 80.02' L _. — �a 77.7�) 62.51' "t..J ,,.. z N 88'15'15" W - _— _ O.�i ` O 26' E MT 3 49 �+�/ � 20' ESMT I —� _ � �— ' � i �. _,,,,,� I �,_,�,a, I wv��oe.n le•ovc�+i— I iHv.we.o��e-rvc-s�, I I , , ...... ..- R I � „ I . I � -��, r�. _ f ;S� `—���l���.� _ —,. �\ � � N+eWC�StI� � � V '} � � - .. .a._ � � �' � - L�����r�T �� � �� � ._.. . _� �� � � F � - : �-� y�� - ; - �_. �,�� �..--- - t , _ �_ _z , � ; � �._. ,�� i__, 4 ; � , , � ` . �.�'.�� _ � �� -__---- � �-----� '- - ite nr-_t� ~ � I i_ _ �I F— T y�a_ ._f '.._.1�. _.,�.�._ �_.a - �, �.. � `�_� ;.- < < _�--, ��__ 1_ _ �� � - r'--- ..r � � �-- ' , �.�yy_., � _ .....- ._._.,.. - - i� �I � �.L._ ��{ � T" ;� T_�._. , �'' - ��[r v i r ._ 1 ___.. �- �._..�.�.�__ , .z � ' _1. � ' ��� � {- �...�.` ,��. ,, � .. .� l ' _ _ ; , , - - r ,��osr---- --- -� i fi i ,_. �� ', � _-- _ � � j a 3 i i. � 'T � i..�, � _ ��S ,_ _ . ; _ �_ ,� i� i -� � 1 L �r .� ._ � �F ! .�,� ��r����_�S. �._-_ �.__ -�� �_ '� --�._ I � �' ar' � _ _.. �- ., : _ . � : _ l _ ,�3. _�. � .�' -. , • - ; � , �� `�l - , . � f _� �_ � 7oifr�r - � ' � _ � -� - - �-- --i-T-^ ',, --�- : ; ; � _ f , � '_ _ r �_~_.�...1.,_.�� i __ -� _ � , _ i � � � . ������ � , � . , • -.-�.� .� i._r .1�:`� ` ' ���, ' �- } � - - ' -- . ` ` � � -i� ¢ : � � � ��,' . _.,,.. �_, . � i , � 1 "�"_ e�� "� �1 , , , � ; ; - � . � � �� �� t __r-- -{�- . ! � i �� F ;, _ _ ; ,_ r_r_ �: � � ,*. � � r . � � ; � � � � 4 . � � "` �� �_ . � � ' � _ � _ ; �� , '�' �` -r� �r � I'� ! '�_�.�a� + �," / , � -,� ,_ � _ :..�_ �{__ _ l _., ; � , � .- ) � ; � uc��r_T ' i I '.NE%M Sf ; . I � Vicinity n/lap ' ' � CS - 33 T24N RSE W 1/2 • RS , - , � w�. _ -- � �.sa.-_ ` R-1 R _ ��P� - -- - _._ __ R-8 ` -- - ; __ , � �. ' i i �'� .V�(.,� ` _.. BE�SNR ._ . ..y��9 . . . NETMi� RC � � '. \ - ,��Q.,�^•. - .... .. _ _". _.. �, : _" " - . .._. i . • ` : i� .... . � —� '_� :....'_. .___. � �`y ' !EMlip : , � � .._. , . .___' -.... . "_. "__' ' SEYlhet.. . ' ` ,.. ; R_B � ; _. 8 �._ ... _ ✓ I � __ _ _... - t" i _ <_ - - --_ �ue;9 �r, . RC �u ({_g" �R-B `- , �yeEa . � s -. - , �� ,' s . .W_.__._ . ' ' �i uEzsns�"�'—��_�..� : . " � g IaON 51 <lE 3lfi St� — � � �� �, r� . . . . .NE 3sm 9 . . . �4 . NE a10�q I � ' . . � . � � .. o R-8 ' ' ' R-8 RC ME ar0 S . NE 3�R � � � R�� R-8 _ : . . . � � . . •��6� . _ � . � �� .�.. ' . . - . . . ' � � �M1 ..... .. . . . .'... � !E IbN S . '. : . . S.... . � . ....�,v � Z �.. ,. N . '_ : € R-8 � R-8_, , d � __ ,. zy r,. - _ � (!1 y �- _ � � � �s7 < R-8 - . R-10 � � __- . _ - r�zids - . m O W � � --o � He:,aa � ._ �. R_8: �.- _ ,�.. � 'r' _ _ � �" H a __ - _ _ _ , ; N R-14 'Z we�onn _R-8 14 �.� R 24 �g Z M � � r� N _ v -.- ��w�s R-14 F"1 e � , _� _ � �R-1�� R-14 a " . R-1 � O — � ' , ?,� _.. . �r � - -.. � � � R-14 � _ �'. ....._ . W NE1BM51 . : m R�� : � � ._...... ,' . . . A - R-8 _ , N _ R-8 �,�� _ - R-14 �, -_ ' �,�n � � R-14 "E� -N_8 . r _�_ R-14^� R'14 ; - - ; .. .. . . . . � i NEl 9 N � ' , � - _.. i .-----_.. "E b, . __._ _ :_ " RM_F � s �,�^-y _ _ R-8 �,�a - � R-14 , "�,�' A-10 � R-10 = C � . w s > : < � ` � .__ ._-_ . � � - . a' .. � M- `� . -- - z > � R-14 � N A= s > � , '�' _ m R-14 ; � f V � RM- Jj_g '- ' _. r�ue,a _ � �, _ � _. _ _.... _ -W RM' , _ NE13V�P/ , ... .. ._. : � . S .____. _ R-1O ....._—._. - �. . .. . .. �y�Pbs�w IE 1Li .-. < . L ' R-10. �`'� . � � .. _ � ,�„ur , - CV i0 _ �R-10 ,_ `,� CV __ V - N �,�� a , _ : �, � �� o = _ : , t � R-10 _ CV .. R-14 � CV CV � 5� N � N � RM-F � � R-14 � CV . Z��� � � i ZONING MAP BOOK ES - 09 T23N RSE W 1/2 PW TECHNICALSERVICES D 5 PRINTED ON 11/13/09 n..ee�.,.Ms,w+M��.wo..o.�on.a� pw.r.e ro v.�.r.�s.�d s e.,ee ve mb.n�Aw�m..rs�adu�rer.oe... • � ��'" `�°'�°„�°`'°�"��" ��re�� 04 T23N RSE W 1/2 I� - Citpnf. ,�_.� _r� .����{��_ `. � iaaoo ,I - 5304 i . � . �Kp6 �� i •�� , �,, � ms �i ;% ) > q�C n Cl � • l�ir, f .x,,, n AkF � ''� 1i. AgC� AmC Ji p� , .4. 1 1 ( ;• a �C1Q p m �...i"� . AgC W � `: JS BM i� wx' ! (� ' I �/' � (+..J t. Pleasure s •! �\120 � a�m r J � " � eM 22 , r Point 21 , .� % F 13 5 :.•� � xiiis � f 1 i. ��I � S � A a l ` � P` ?� ,,G�: ;r: I l;r AmC �22\ gC � '� � � � azelx�' ' • � � J �.'�.. 'I - � .f ' • � • � � � • . Ir(' � , ., � � i �� P`gC � � � 1 a1;F��� �� � ',��� • � AkR ------- :- p6" ' �i •BM �-�� B .'/ 29 2d3 7A € � � 42 � BeC -�� KPp ` /! �A C'.�e � � ( .: - �i�• J „l qgC r � Kp B- t 'PineS � rTewpo� A�� S� E,�:c \ ( ' ' \ � Hills� ��-` s�c i � InA • r �n'� , . I AgC -- � - - / . • .v '� � •�n � W I 4mC +, � I �c, . Lr . n � n Evl3 y � � 1 �1( •KpG�r � i � d � �, g�� ���/��'•� J � I� -��k! f e� �' I� �' I v �e, ' � � 2� � �" i 1 1 p Iv � '�� / �c AG�, 3 . \ �� M.�. � � �c • �� i�� �BM i � �398� ���1,�,• L C �, — ( I E:�C � � �LoC 1 58 � AmC � � �\ �'��° � ' �' �� ��. ' � •• �i �h �� ���� �' •�� i�' } \' i . I i A C � Q. � R � ,� � May e � 1, 11`'���._<�f �t• � .E�c �� �� ��: � � I09 • �� .-t'; .� � OvD �9� � . .•\ _ �\ � .�,�'• � O �o r\ \ . J � �S" Bt�a j. q�p^� . . ------ --�-'_'---- : 'f= - - BM� �BM J , � � \ �{ � , l 690 g97 �' t • ' ,,,� � _ � •q�C t �d, �� • Na `���^ � _ •,•� AgC ; c � I �° - '„l l �\ � BM 605 � j , :: /• �• -Ci � . . ,� I� ` � �\�� , •� � o G� • J C � ,S{m , : ,•• r�� m • \\ � • �- /;� .�`l � �� � � BeC / ��C 15 � _— . � �AgC � � � •: _ ��� ' / ;�' 2 � A D � '� AoD � Q�r� �" 34( � '� \ .. g . ..��,. t�`� '� AgD � \ . �� � •�• � , q€C ,��� � �' •�� • Kennydale� • o i:' ' >;,• i;� •".'�. �'� . ..::/ •InC AkF �'••� ./ ("�. ,. • r' �� AkF. �•� I Ak F \ ��� � ' .• I pgC EvB � _ �ty � ,ti�� � eeG E�C. �man Poin Q�! ' F'" T L � �o, �� . �• � ' AkF � '- C'h 1306 . � �<_ �inA� 1 � � e� 4•, AgC • ' , B .48� AgD� -Z 4-- ----- -- \i " BM�11 �v8 ---- --- - -- —�� v� � n .';. ... •BM'a0.� \` � r x. .��t �_ ...` l '+ � n E��^�J � ui� Iw ��� T A C . • J . �'": �: - • �. _��% ,�•' • � �� 11 -_� '�-' BM� 1 '�. t:, ' 4 � ` , ..y `�; — ,o AkF � p' � , � n- . �: i`� , ':c.. ,� i� u . • `�tii� il �� ar . - " _ .AmC . r�,� ' .�.: �� ;,.-� 4mB, �I ' r- - --- " • � ^ • • k•� S s.� • e:p�y 1 s_ _ • • ' � '• .i � � . , tii x tt" a t-• f Srn• .l• .�l` ,L�V 1 i _ "' t' .�je �c,�.• � J 1- -. :,'. ..t � •�• In:, • - , 1J ' � Fy � . j., r i/i` M �x. T, _ EvC' �f ' . �r:' ^r3�i rx. �Y: �t t �� � s �� .• ,: I ,, ,� ,�'�� ''f � . .. , � ,�� � _, -� t .• z, �4. , . F x. ,;�i� T�'��.-��?'.ti{ �''f�'i�; �'F. .. -. .'" . ., _'�. ,.i+ •' � 7 � jr.. �' � I�•eA$C � , . �'�`�t^rk}z , �:s... �v' :(�-tl-ln���'_�_T�,� ry �;. �f^!,� •�.t �:':t :n'`� I . � � King County Department of Development and.Environmental Services TECHNICAL INFORMATION REPORT (T1R) WORKSHEET _ Part'f PROJECT=OWNER;-AND : ;:` ; = ;Part 2 PROJECT LOCATION AND.._ =. . ._ , PROJECT.ENGWEER � : �: : '� .'` - DESCRIPTION -` Project Owner Project Name ��� �� v �. (� ��s ��A�-�"s 5 �. r �oL�-� Address G���������� Location -���'Z� Township Z.3 Phone � SS���H C�RjOZ� s Z�i' . �y�- —(06�b Range Project Engineer .�.w••.Section ��- Tom ������ Company �N G / 55 �n/GC. Address/Phone L S� 3 2'4250 Part 3 ;-F1'PE;C?F PERMIT` Part 4 -OTHER FiEUIEWS AND PERMtTS �'� �APPL�CATION <.. " , , . _.;` �_ ,.. - � , ._ - ' Subdivison � DFW HPA Shoreline Management , x Short Subdivision COE 404 Rockery ( . Grading � DOE Dam Safety Structural Vaults Commercial FEMA Floodplain Other � Other COE Wetlands - _ ;,. ,� ,; � . - , :;, _. _ P_art 5 erS1TE COMMUNiTY=AND'DRAfNAGE BASIN ; ; ,„ :� _ �; � Community . Drainage Basin ��0�� ( ��` /`-' Part 6; .SiTE`CHARACTER1STlCS River Floodplain Wetlands Stream Seeps/Springs Critical Stream Reach HiQh GroundwaterTable Depressions/Swales Groundwater Recharge Lake � Oiher Steep 5lopes Pait 7 .:SOICS' : . ; � - Soil Type Slopes Erosion Potential Erosive Velcoties rti�p i��^�A-N D 1 �/A *" Additional Sheets Attached Part 8�; DEVELOPMENT L{MlTATIONS REFERENCE LIMITATfON/SITE CONSTRAINT Ch. 4—Downstream Analvsis LEV�L � �� �(gl�5 M,�1 r n,?S . Additional Sheets Attached , % r r Part 9 ESC fiEQU1REMEf�1TS -: �5 _ _ - _�._,.:... �_: ._ � >: :,i ^ :x MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION ✓Sedimentation Facilities ✓ Stabilize Exposed Surface t/ Stabilized Construction Entrance . �/Remove and Restore Temporary ESC Facilities ✓Perimeter Runoff Control � ,� Clean and Remove All Silt and Debris Clearing and Graing Restrictions Ensure Operation of Permanent Facilities ,/ Cover Practices Flag Limits of SAO and open space Construction Sequence preservation areas Other Other �Part 10 �SURFACE 1NATER SYSTEM _: - Grass Lined Tank Infiltration Method of Analysis � � S Channel Vault Depression ��� Pipe System Compensation/Mitigati Energy Dissapator Flow Dispersal on of Eliminated Site Open Channel Storage Wetland Waiver � Dry Pond • Stream Regional Wet Pond Detention Brief Description of System Operation 1�1 r�L�iQ-7B1� �Yl,�ill�}-�I�rS ���_ R�,�s � �R�v�� , Facility Related Site Limitations Reference Facility Limitation __ _ _ _ �. � __ , . , : . _, - . , . . ... _ _ ._ __,. :Part�11<..STRUCTURAL ANALYSIS -�� _: �Part:�2,;EASEMENTS/TRAGTS - _ Cast in Place Vault � Drainage Easement Retaining Wa(I . � Access Easement Rockery>4' High Native Growth Protection Easement : Structural on Steep Slope Tract Other Other .,. ..., . . - �._ ::.: . -Part'13 SIGNATUREOF,;PROFESSIONAL"ENGINEER _ .__ - I or a civil engineer under my supervision my supervision have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attachments. To the best of my knowledge the information provided here is accurate. c�-,..-✓l�-- O[� /l//� -T Si ned/Dat� SECTION 2 CONDITIONS AND REQUIRMENTS SUMMARY 2009 KC SWDM Core Requirements Section 1.2.l Core Reqmt#1: Discharge at the natural location • The site drainage will continue to discharge at the natural location, infiltrate into the ground. Section 1.2.2 Core Reqmt#2: Offsite Analysis • An offsite drainage analysis is provided in the TIR. Section 1.2.3 Core Reqmt#3: Flow Control • Flow control is not required on this project. Full Infiltration BMP's will reduce runoff from the site to less than 0.1 CFS, the threshold for formal flow control. Section 1.2.4 Core Reqmt#4: Conveyance System • No conveyance pipes are being proposed. Section 1.2.5 Core Reqmt#5: Erosion and Sediment Control • A temporary erosion control plan will provide BMP's to be implemented during construction. Section 1.2.6 Core Reqmt#6: Maintenance and Operations • A maintenance and operations manual is provided in the TIR. Section 1.2.7 Core Reqmt#7: Financial Guarantees and Liability • The developer will arrange far any financial guarantees and liabilities required by the permit. Section 1.2.8 Core Reqmt#8: Water Qualit}� • Water quality is being provided by directing runoff from the onsite joint driveway to a filter strip.. 2009 KC SWDM Special Requirements Section 1.3.1 Special Reqmt #1: Other Adopted Area-Specific Requirements • N/A Section 1.3.2 Special Reqmt #2: Floodplain/Flood�vay Delineation • N/A Section 1.3.3 Special Reqmt #3: Flood Protection Facilities • N/A Section 1.3.4 Special Reqmt#4: Source Control • Source control is not required for this project. Section 1.3.5 Special Reqmt#5: Oil Control • Oil control is not required.