The URL can be used to link to this page

Home My WebLink AboutZMA202100009 Application Steep Slopes 2021-07-19 OLD IVY RESIDENCES PRESERVED SLOPES ZONING MAP AMENDMENT JULY 19, 2021 PREPARED BY: s � �� . s � �� TIMMONS GROUP YOUR VISION ACHIEVED THROUGH OURS. 6OR PRESTON AVENUE, SUITE 2OO Cxaxr.oTTEsvi�r.E, VA 22903 BRYAN CICHOCKI, PE Introduction A zoning map amendment is being requested per Section 30.7.6 of the Albemarle County Zoning Ordinance, to convert an area of preserved slopes to managed slopes within the Old Ivy Residences proposed development. The slopes that are being requested for reclassifcation, while 25%or greater in slope, are misclassified as preserved slopes and better described as managed slopes, as they are manufactured, which is made evident from previous documented site plans. Furthermore,the overall development plan is to reduce the area of these steep slopes, laying back the slopes, further reducing concerns of erosion and downhill degradation of waterways. While these slopes are being requested to be changed to managed slopes,there is a recognition of the County's goal, related to steep slopes,to reduce "rapid and/or large-scale movement of soil and rock, excessive stormwater run-off, siltation of natural and man-made bodies of water, loss of aesthetic resource ... all of which constitute potential dangers to the public health, safety and/or welfare." With that in mind, this application will discuss the following related to the conversion of these slopes to managed slopes: • Explore the existing conditions and designation of this area as preserved slopes versus managed slopes. • Protection and enhancement of adjacent and downstream land. • Mitigation efforts to eliminate effects of slope impacts Existing Conditions The property containing the currently designated preserved slopes within the development (parcels 06000-00-00-024C1, 06000-00-00-024C3, and 06000-00-00-024C4) is located off Old Ivy Road and the 250/29 bypass within Albemarle County.The subject portion of the property is adjacent to parcels 06000-00-00-024C and 06000-00-00-05100 (which are under the same ownership)to the east and the 250/29 bypass to the west, as shown below: 1 � Page .. �' ` • fY� � ..�� • .� " f § . :�'O - � ' 2(Oj ' � ..ef„ '„ � : ��! ^�''J/`f �s . I 1; .� PRESERVEC �,a� 7"� � ' .,i'� ^I� 5-OPESTCEE �r � �r� r' �"`� ICIPACTED '�� .. . '� . �'�' � s;,. " ,. � _ i �/. � .. �e`'� - 'y', �� — s � �'. Y; , I _ � �� . � �� t,�:,u ��'�� '�✓ ' r; �s;<-� ��`�� , S P �y -. �� R�` ♦ � ,n. . � f ' �Z�� '. � ,,�e. • ,�.P � �rt.!:.. � � ' /.'�a � ' r,: 'r�l �,� �,y � �, ��, �bY�� .�)k „� ,��`�� + �, . �r� rs °+� ' t� a `� y, ��' " H. t� g 1;,;�,yi+ r: �i � t`, ��t-� �� v � ;�Y � �� ' � � � � , + t �I�.� � � �� ,.��' � � �''�;., �' -. � i, � , '� ,� ti �,�:� � � , ;,� � -� . �Y �� ,. -, � � � '� ��l\ ` ` ' ._ y ._� � ,".� %�� b. . -'01 ,� b �' �. �� .� -a_� . r� � i .:4� . ��i'�� w.� �� l�1,:' � n..�.+ �`• ',as . a �T Figure 1:Slopes to be converted to Managed Slopes Per Albemarle County GIS,there are designated qreserved sloqes on this qarcel, comprisin�an area of approximately 1.54 acres (outlined in green above). Per Section 30.73,the origin of preserved slopes is defined as natural features protected by county action from land disturbing activities. However, both of the preserved slope areas identified on-site appear to be the result of human activities. Historical imagery shows that slope "A" (adjacent to the 250/29)was a result of activity on the site in the early 1990's. Slope "B"was a result of waste fill generated from the North Grounds Connector Road project in the mid 2000's (see Figure 2 &Appendix A for further details). Under normal conditions outlined in Section 30.7.3a, this would likely lead to the classification of these steep slopes as managed slopes; however,they are currently classified as preserved slopes. We believe that the history of these slopes is an important factor in the consideration of this zoning map amendment to reclassify the slopes as managed. 2 � Page s..n IJi�I.... �G . •',.'$ � \ .¢i . . - Ry. ..a/-�.` . . J - .. ' .. __�.. `..-""". . . . r4 . , , IE� � .. q;... _ * -...- �-J \J ers /�a—_ _ � � =��y/ ' .' � ��vc.�u EC 8 _ � . i I I 1^';� V / ��y�� I�' �,� � �� EC- �, , 'a � _, � i' j` �� I �i � � �.� a � _ � ��, �� / � CONSTRUCTED i � , :�. �� /) (t STEEP SLOPE ` � JIf1�\ /\ . ��8�� ,�a�� sj' .-� \ < _ � , ,. .. ; :. - -`=�.-�. —--�.: �� . , \9. $ , Figure 2: Excerpt from North Grounds Connector Road Project Protection ofAdjacent and Downstream Land Protection of adjacent and downstream land is an important consideration for any development, but particularly one that has both intermittent and perennial streams located within it. As noted below, development has been located to limit removal of forested areas,while protecting the natural area of the Rivanna Trail. Additionally,the impacts to the slopes will reduce the steepness of these areas, as well as the overall runoff across these slopes, reducing risks of erosion and/or slope failure. Proposed with the Old Ivy Residences rezoning application is a new residential development on the subject property.The proposed development has been laid out to limit disturbance to the steep slopes, while maximizing the conservation of forested areas, particularly adjacent to the existing Rivanna Trail, as much as possible (see Figure 3). Specifically,the development layout focuses on utilizing space already impacted bythe existing farmland to minimize the disturbance to the surrounding forested areas, as well as some of the managed slopes which are identified in these areas. By impacting a portion of the currently designed preserved slopes,the neighborhood layout can better preserve existing natural forest, which provides an invaluable amenity to the neighborhood, prevents additional environmental concerns associated with deforestation (erosion, stormwater quality, habitat, etc.), and provides a greater degree of conservation. Given the history of the slopes on-site, Greystar and the design team agree that these forested areas hold a higher environmental value on the site than the previously disturbed, man-made slopes. Moreover, the impact to these slopes will result in a reduction to the stormwater that drains across this area, as the slopes will be reduced (the grade proposed is to cut these areas down in elevation), while 3 � Page also capturing runoff in a stormwater conveyance (pipe) system, reducing overland flow and the total amount of runoff that these steep slope areas currently are subject to from a stormwater volume perspective. This change will result in a reduction to the potential of erosion over the remaining slopes, since those areas will see a limited amount of drainage over top of them. � .*i � / " �� /� � � �� "� � �,:. �� ., . / / l i�; . � � � . , �_ �;- �%_, \ / � EXISTING PRESERVED �' PRIORITIZED . ' �'�( .� ` SLOPES PROTECTED � �� ' � � �� •�1 _ _ FORESTED � O� ' ' . ��T�'" ��- {.'�.« 'r �" ;,'("t r.tv' AREAS NEAR � p ;s �y�.,�� ' ' THE RIVANNA ,^.'- �.1,. � . q ��7��5, � _� TRAIL ' �A �y� fF •} � i�.�. , � i� ..�'.} t . �.. �' �� '{�C�'�.�i ' � . �� M �r ., i �y r f ,i � . r �. . . s .� - �t " i i 4p'�s�'- ' �f ' ' ' � . �t�K . .t� C!. �� .�F i.�,�l � �y � l ,�( a,��k� c �� ., �4t� ��1t��.� '1 �� % f � �' ., � `f�`� � r , LAYOUT TO �` ��T�� !'�t. � �, �� , F' ;YS��,�a;Q� 4+ MINIMIZE � ,;.. �:' �� +�i. l .�, IMPACTTO - ti''� /' t(„`•�tit + �'._ E� � ;�. FORESTED ��' �� `'�r �� a��; � � AREAS - -� �'�� , , ,� � : '� ,.� � � ' ' s � .w �,�, . � �� . . � � � � � � i�,, f'��'' '� ' • � . ,� .e� � t �� .. �: ��-�A -,.! , �f y � L` C,�t�- � / 4 ��. ` �,�, I • �� 1'i � ° �: ::I � �s7� .l tai Figure 3: Residential Layout to Minimize Impacted Forested Area The proposed impacts to the existing preserved slopes are as shown in Figure 4 below and included in Appendix A: 4 � Page � , ,—�-��.d��.�_�. , - � _ p �, A�� _ ao 0 E��,� � � , ,- �� s � �� , �, f �� r:�, � �� _ ,,� � �a � � �r�� r� _ _ , - , r -- - . _ �` �; - - _-,; ';;r._ � , ` O oe " � /,i � o / � ___ � '� . Z o , ,i O $ —�� n � f r� � -__�//;` �;', ��° l � Figure 4:Areas of Preserved Slope Disturbance On-site Mitigation Efforts In order to protect downstream land, adequate erosion control measures reviewed and approved by Albemarle County will be implemented during construction to mitigate runoff while preserved slope disturbance takes place. More specifically, downstream measures, such as wired-backed silt fence and sediment traps/basins will be required. Each of these measures will be placed in a way to ensure protection of the downstream lands, including the pond and beyond. Furthermore,the overall project is proposing to desilt and improve the existing pond to enhance the ecological benefits forthe local habitat, improve the environmental impacts by adding vegetation and aquatic benching,while providing volume to meet stormwater quantity requirements. Conclusion While the steep slopes overlay district strives to protect preserved slopes within the County, it also affords relief through the zoning map amendment process when certain slopes are outside the criteria of those considered preserved slopes. Given that these preserved slopes were previously disturbed and generated by construction and waste fill, it stands to reason that they should be considered managed slopes. Additionally, even with this designation,the proposed impacts will further enhance the downstream waterways. While the proposed impacts do reduce the steep slopes within Albemarle County,they ultimately enhance and improve downstream receiving waters, providing a betterment for the County, environment, and future population that resides at the Old Ivy Residences. S � Page Appendix A OLD IVY HISTORICAL IMAGERY NORTH GROUNDS CONNECTOR ROAD PROJECT WASTE FILL PLANS OLD IVY SITE PLAN 6 � Page