Morrisville Unified Development Ordinance - April 2019

Article 6: Riparian Buffers Section 6.9. Mitigation 6.9.1. Applicability

Table 6.8: Uses and Activities Permitted in Riparian Buffers

Allowable with Mitigation [3]

Use or Activity

Exempt [1]

Allowable [2]

[3] Uses and activities designated as ”Allowable with Mitigation” are allowed only if no practical alternatives are available and on approval and issuance of an Authorization Certificate with a mitigation strategy in accordance with Section 6.5, Riparian Buffer Development Review, and Section 6.9, Mitigation. [4] Perpendicular crossings are those that intersect the surface water at an angle between 75 and 105 degrees. [5] Overhead electric lines crossing Zone One shall comply with all of the following best management practices, unless the Town Engineer finds no practical alternative exists to such compliance per 6.5.2.: • A minimum zone of 10 feet wide immediately adjacent to the water body shall be managed such that only vegetation that poses a hazard or has the potential to grow tall enough to interfere with the line is removed. • Woody vegetation shall be cleared by hand. No land grubbing or grading is allowed. • Vegetative root systems shall be left intact to maintain the integrity of the soil. Stumps shall remain where trees are cut. • Riprap shall not be used unless it is necessary to stabilize a tower. • No fertilizer shall be used other than a one-time application to re-establish vegetation. • Construction activities shall minimize the removal of woody vegetation, the extent of the disturbed area, and the time in which areas remain in a disturbed state. • Active measures shall be taken after construction and during routine maintenance to ensure diffuse flow of stormwater through the buffer. • In wetlands, mats shall be utilized to minimize soil disturbance. [6] Poles or other above-ground utility line infrastructure shall be installed within 10 feet of a water body unless the Town Engineer finds no practical alternative exists to such location per 6.5.2. [7] Underground utility lines crossing Zone One shall comply with all of the following best management practices, unless the Town Engineer finds no practical alternative exists to such compliance per 6.5.2.: • Woody vegetation shall be cleared by hand. Felled trees are removed by chain. No heavy equipment, land grubbing, or grading is allowed. • Vegetative root systems shall be left intact to maintain the integrity of the soil. Stumps shall remain, except in the trench where trees are cut or removed by grinding. • Underground cables shall be installed by vibratory plow or trenching. • The trench shall be backfilled with the excavated soil material immediately following cable installation. • No fertilizer shall be used other than a one-time application to re-establish vegetation. • Construction activities shall minimize the removal of woody vegetation, the extent of the disturbed area, and the time in which areas remain in a disturbed state. Disturbed area shall be stabilized with native vegetation. • Measures shall be taken on completion of construction and during routine maintenance to ensure diffuse flow of stormwater through the buffer.

[8] Neuse River Basin Only. [9] Jordan River Basin Only. (Ord. No. 2014-006, 05/27/2014; Ord. No. 2016-001, 05/10/2016, Ord. No. 2016-054, 11/22/2016)

SECTION 6.9. MITIGATION

Applicability

6.9.1.

This subsection applies where a Riparian Buffer Development Review application proposes a use or activity listed as “Allowable with Mitigation” in Table 6.8, Uses and Activities Permitted in Riparian Buffers, or where mitigation is proposed or required as a condition of approval for a Riparian Buffer Variance application. Any application for Riparian Buffer Development Review or a Riparian Buffer Variance that proposes mitigation shall include a written mitigation proposal that calculates the required area of mitigation in accordance with this Section, and describes the area and location of each type of proposed mitigation. The applicant shall submit to the Town Engineer a mitigation proposal in accordance with 15A NCAC 02B .0295, Mitigation Program Requirements for Protection and Maintenance of Riparian Buffers . The applicant shall not impact buffers until the Town Engineer approves the mitigation plan and issues written authorization. The NC Administrative Code (NCAC) is available at no cost from the N.C. Office of Administrative Hearings at: http://www.ncoah.com/rules/ .

(Ord. No. 2016-054, 11/22/2016)

April 23, 2019

Morrisville, NC

Page 6-18

Unified Development Ordinance