Loading...
HomeMy WebLinkAboutGrading Plans - 05/23/2017• ' • t N C O R P O R A T E D May 23, 2017 JD Enterprises, Inc. 3215 Coneflower Court Fort Collins, Colorado 80521 Village West 4th, Lot 52 B1701318 Grading plan & drainage memo accepted 5/23/2017 DM Attention: Mr. Jay Detweiler Subject: Drainage Memo 1825 Essex Drive Fort Collins, Colorado Project No. WY01457-500 Dear Mr. Detweiler, The above referenced lot has a historic drainage issue. Topo provided for the lot shows that the east lot line drains as a"B" lot (two high points, one on each side-property line with drainage to the back- property line and to the front-property line). There is a high point approximately 40' off the front property corner. Based on the 1971 development plan prepared by Nelson-Haley-Patterson and Quirk (NHPQ), this lot should be an "A" lot (one high point in the back with wrap around drainage to each side to the front-property line). After reviewing this development plan, the proposed grading by NHPQ was inadequate and would not have provided adequate backyard drainage. Based on the inaccurate grading on this lot we are unsure of the overall subdivision grading and drainage. At this time the lot drains as a"B" lot and partially drains to the south. Where the drainage runs to once it exits this lot is unknown. We discussed the drainage of the existing lot and possible drainage options for the proposed addition with Dan Mogen of Fort Collins Storm Water. The proposed addition adds impervious area to the lot that currently does not exist. We agreed that if we drain most the new impervious surface water (the downspouts on the east side of the addition) to the front as originally intended and the remainder (south and west sides) drains to the south as it has historically drained would be the best option. We have added a buried 6" diameter PVC drain line on the east side of the property that will collect all the east side downspouts and drain them to the front lot corner. The end of the pipe will be secured in a short grouted boulder wall that starts a graveled dry stream bed that drains to the back of walk. The additional drainage that runs to the south should be minimal compared to the current drainage. The buried drain pipe will need to be maintained and kept in good operation to provide drainage to the front lot line. This will involve cleaning out Isaves and roof debris from the gutters, downspouts and drain pipe on a semi-annual basis. This will also include maintaining the end screen to keep out rodents and other animals and allow for proper drainage. As we discussed with Dan Mogen of Fort Collins Storm Water, this is the best option for drainage we have based on the existing conditions and the surrounding elevations. It is our opinion that the proposed site development will not cause adverse impacts to the adjacent properties. Attached is the proposed site plan with proposed top of foundation elevations, proposed buried drain line and existing grade elevations for reference. 1103 Old Town Lane � Suite 201 B � Cheyenne, Wyoming 82009 � Telephone: 970-206-9455 � www.ctlt.com Thank you for selecting CTL�THOMPSON for your engineering needs. When we can be of additional service, please contact the undersigned. Very truly yours, ,;;��`'��jp ��c CTL�THOMPSON,l�I�C:' .•�'KN.F�, ' �'�s ��`o - �� ° : 38108 / vS,/�J�7 / yatt M. Knutson, �,.;•.. � �,,� Division Manager c,'�,...; ��y�..�� �+ ; . , � :i'.' Attachment: Site/Drainage Plans I., - � �-�' 5.� ��•-n�, I I I 1 �r 1 ��I � - , I �` �i � . - SZ�� °c�`_ ,i � ' �� ' � , a �3� 3�' f - " , �.�9 , — " � 1 ��_ ,;,,E�'�` � � 1 ` .- , \ - �� r r ..`._ _...-- a� _ .� . „7 ��., ___._ _ --- � wx� as� , _ ;� f �+ .. �44c1ct�rb.1--_—�._ :; ;�; ` � —___, --- ;-.,�: � �� V � ! - _ � ���� .�' � ...._,_� /`� j ,p�n � . � ! � �-•e-- � � . � - --- 0 V �-�� 1 � ----- � � f ` .�=� ,. � , � . _. s� -� o� ,� � , l � �- 1 / . s r,�,� - - ��i r.�%� �^ _+� e `p � ' ���-' Dr. vr �0 � •� �i / ,`�\ � Z�p'� / � � / � � \ �� �v `� o � �' �L�� � �.,� ii�,� i � ``�,% � , ���� � f ,��� �. ��,,,.,�J o�..- �; , , f �5 � /;�, .��� � � o � �� �y� ,�,x j � t��k' , �s� � �� �� t z � � � 0 l �_ � ' t�� � - 1 � �t �� �1 , . � � , `� G�,,�. p.� ��� � � i �� �'r � �K..w �.,< R� �..4 � Q �� � � � s��� �41J.� ��i � _�.. / D�-,� O, p�,4 7ib SPGc. rY � v� r � .,\ Q r..a �.s �4..: ,��� � � �le. � � _� cQ b-. � . ����� - o j Z' �g{`�-�- J�1 �� ��o Ew i�� .� �l03 / _��.L.��1��r. j]��+�/'-�-� ` � --- � — � �" , _ t� �� = � - _� , a� �� I D� " $2.._ �� o C9 3° � - , " ,` ��y9 3 , !-r — � 1 �•q �U� _ ' � ; 1� _ � "fE _ � �1., - , . �� � _c.. �, ` S. v , I `` I A ' rr �'� ,� j � �' $ -? , j ,;; �y + �/ y� o ! � ' ' - , � , ---� . ,_ � ��.g'� � � �f�.�i 7� i I . _...�_�-___..__ .. � �I — �t'Lc?P���� 1 ,,� , t;, k �7' n (.���:=r=�o,v- -- " ���' f�' �1r ! . ` , -._. � � ��r � , � ��-- � — �, -�o � �� �: ,,, ; � � � �; - - __ __._._ � �, ,,�� _ . �.;r, � .r� � —�Y---- �H�'� � , , �� �' :'1�� 1 . ; . . ���' � , ��..�_ . o _ �� 1 �, �.�� � ���-�� - � \� , � -�---.. , ..�r�pa ��_ -�� �q� ' '�-0 3 :. :.� _ i� S.g � , Y 1 --�lrS/�.LlE�fc _. ,, ' 18=0' ' i� %� - �/, s`7 �- /i. � 1 � •7G.3 � 7 � ` �/s� • / ��� �! / . ' � 'u • � � / � � _ � � .v I � � � � �V�� � � �^ � ���, m.�>v � / �, � i . �' f�/�i� /��. ���i� � / �• � . La �'i �` .. � �� �� t , J � } � ' a � � y .- � . �� � � �_ � �. ,y . \` , � , ',�� � , �, _ �� :� � 1 , o.. f � , �f r�r-�[� , � '8. o, -�` J v� - � 1 Z� � 0 2' ��� �— _ - � / /-��� �If �� J ��o Ew r ��� i �— � ° E�' � `-7�3 ��c'��11�t�}�Ey. �.Ex / EF``''�r�. � �T���� ' _ ,� t,v _ t- _ ., ; �