Morrisville Unified Development Ordinance - February 2021.2

Article 6: Riparian Buffers Section 6.7. Diffuse Flow Requirements 6.6.3. Riparian Buffer Variance Review Standards

9. Granting of the Variance would assure the public safety and welfare, protect water quality, and achieve substantial justice; and 10. The Variance is consistent with the Comprehensive Plan. B. Insufficient Grounds for Approving Variances The following factors shall not constitute sufficient grounds for approval of any Riparian Buffer Variance: 1. A request for a particular use that is expressly, or by inference, prohibited in the zoning district or the riparian buffer zone; 2. Hardships resulting from factors other than application of requirements of this Ordinance; 3. The fact that land or a structure may be utilized more profitably or be more marketable with a Variance; or 4. The citing of other nonconforming or conforming uses of land or structures in the same or other zoning districts or riparian buffers. SECTION 6.7. DIFFUSE FLOW REQUIREMENTS Diffuse flow of runoff shall be maintained in the riparian buffer by dispersing concentrated flow prior to its entry into the buffer and reestablishing vegetation as follows: A. Concentrated runoff from new ditches or man-made conveyances shall be converted to diffuse flow at non-erosive velocities before the runoff enters Zone Two of the riparian buffer; B. Periodic corrective action to restore diffuse flow shall be taken as necessary and shall be designed to impede the formation of erosion gullies; and C. No new stormwater conveyances are allowed through the buffers except for those specified in Table 6.8, Uses and Activities Permitted in Riparian Buffers, addressing stormwater management ponds, drainage ditches, roadside ditches, and stormwater conveyances. SECTION 6.8. USES AND ACTIVITIES PERMITTED IN RIPARIAN BUFFERS Table 6.8 sets out potential new uses and activities permitted within a riparian buffer, or outside the buffer with impacts on the buffer, and categorizes them as “Exempt,” “Allowable,” or “Allowable with Mitigation.” All uses or activities not listed in the table shall be considered prohibited and may not occur within the riparian buffer, or outside the buffer if the use would impact the buffer, unless a Riparian Buffer Variance is granted pursuant to Section 6.6, Variances from Riparian Buffer Regulations. Table 6.8: Uses and Activities Permitted in Riparian Buffers Use or Activity Exempt [1] Allowable [2] Allowable with Mitigation [3]

Access trails (pedestrian access trails leading to the surface water, docks, fishing piers, boat ramps, and other water dependent activities) [9]: Pedestrian access trails that are restricted to the minimum width practicable and do not exceed 4 feet in width of buffer disturbance, and provided that installation and use does not result in removal of trees and no impervious surface is added to the riparian buffer [9] Pedestrian access trails that exceed 4 feet in width of buffer disturbance, the installation or use results in removal of trees or impervious surface is added to the riparian buffer [9] Airport facilities that impact no more than 150 linear feet or 1/3 acre of riparian buffer Airport facilities that impact more than 150 linear feet or 1/3 acre of riparian buffer

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Morrisville, NC

February 1, 2021

Unified Development Ordinance

Page 6-11