Riparian Area Management Plan - Durham, NC

Riparian Area Management Plan

City of Durham Durham, North Carol ina

April 2016

City of Durham Riparian Area Management Plan ii

TABLE OF CONTENTS

Section 1: Riparian Area Management Plan ........................................................................................... 1-1 1.1 Purpose of the Riparian Area Management Plan ...................................................................... 1-1 1.2 Riparian Area Management Plan Background ........................................................................... 1-1

Section 2: RAMP Implementation........................................................................................................... 2-1 2.1 General Approach to Riparian Area Management Plan Implementation ................................. 2-1 2.2 Department of Parks and Recreation ........................................................................................ 2-1 2.3 Department of Water Management .......................................................................................... 2-1 2.4 General Services Department .................................................................................................... 2-3 2.5 Public Works Department .......................................................................................................... 2-3

TABLES

Table 1 Sanitary Sewer Outfalls Selected As Reduced Width Mowing Pilot Areas

APPENDICES Appendix A No-Mow Fact Sheets for Parks and Sewer Easements Appendix B Pilot Study Areas for Reduced Width Mowing in Sewer Easements

City of Durham Riparian Area Management Plan 1-1

Section 1: Riparian Area Management Plan

1.1 Purpose of the Riparian Area Management Plan

The purpose of the Riparian Area Management Plan (RAMP) is to address protection and maintenance of riparian buffers on property, utility easements, and greenway corridors owned or maintained by the City of Durham along streams within the city limits. Many departments throughout the City routinely interact with riparian buffers while conducting operations. The day-to-day work decisions and actions of staff that frequently interact with riparian buffers can affect the health and water quality of streams, wetlands, ponds, and lakes within the city limits. These activities occur on a broad range of City owned and maintained properties such as pipes, structures, and easements associated with water, sanitary sewer, and stormwater, and parks and recreation facilities. The RAMP identifies opportunities to enhance or extend riparian buffers or to change maintenance practices to help improve waters quality on City owned or maintained properties.

1.2 Riparian Area Management Plan Background

Riparian buffers are important for protecting stream banks and shorelines from erosion and pollution, dissipating high-energy flows during storms, and providing fish and wildlife habitat. The State of North Carolina implemented riparian buffer protection rules for the Neuse River, Jordan Lake, and Water Supply watersheds. The City’s Stormwater MS4 NPDES permit also includes stream buffer requirements. The primary way that these stream buffer requirements are implemented is through the Durham City-County Unified Development Ordinance (UDO). Requirements are found in Article 8.0 – Environmental Protection of the UDO and the requirements are updated periodically. This webpage has the latest update: http://durhamnc.gov/414/.

The Stormwater and GIS Services Division (City) within the City of Durham’s Public Works Department implemented their watershed planning program in 2007. The Program seeks to protect and improve the water quality in Durham’s watersheds and to help to comply with water quality regulations issued by the State of North Carolina. The City has completed Watershed Improvement Plans (WIPs) for four of the Durham’s major watersheds, Ellerbe Creek (2010), Third Fork Creek (2012), Crooked Creek (2013), and Northeast Creek (2013); and is currently preparing the WIP for the Little Lick Creek Watershed and the Eno River Watershed.

In each of these watersheds, field work for stream assessments included evaluation of the land directly adjacent to stormwater ditches, streams, rivers, wetlands, ponds, lakes, and reservoirs. The process of gathering data for each WIP involves conducting field work for stream and SCM assessments. This provides opportunity to observe the condition of riparian buffers throughout a watershed. Despite the various regulations protecting riparian buffers, a lack of intact riparian buffers, eroding stream banks, and dumping of pollution and trash are common and visible problems that are noted during the assessments of riparian buffers. These issues also occur on stream buffer areas owned and maintained by the City of Durham.

The initial RAMP was prepared in September 2009 as part of the Ellerbe Creek WIP. In September 2010, several revisions and updates to the RAMP were added as part of the Third Fork Creek WIP. As part of the Northeast and Crooked Creek WIP, the Stormwater and GIS Services Division coordinated with Parks and Recreation Department, focusing on their mowing practices within riparian buffers in City-maintained parks. As part of the Little Lick Creek WIP, the Stormwater and GIS Services Division coordinated with the Water Management Department, focusing on their maintenance practices within City-maintained utility easements. Section 2: RAMP Implementation will further describe these initiatives.

http://durhamnc.gov/414/


Section 2: RAMP Implementation

2.1 General Approach to Riparian Area Management Plan Implementation

Previous RAMP documents have focused on general project planning, design, and maintenance strategies for City maintained facilities and property such as maintenance yards, utility easements, parks and recreational facilities, stormwater control measures (SCMs), and flood control projects. Initial steps for preparing a specific plan involve examining existing GIS data of city owned and maintained properties and conducting preliminary analyses to identify riparian buffers. Field work is conducted to evaluate these areas and better characterize potential issues and solutions. Coordination with an individual department or group of departments is required in order to develop specific recommendations. Given the interrelated nature of activities on City-owned properties, coordination with several departments may be necessary as part of this process. Recommendations are documented in an implementation plan memorandum in order to capture items such as timeline, scheduling, expectations, and/or specific sites or pilot locations where practices are to be implemented. Once implemented, the practices can be monitored and adjusted for effectiveness.

2.2 Department of Parks and Recreation

Streams and riparian buffers are an integral component in many of Durham’s City parks. The Department of Parks and Recreation took steps by preparing an inventory and mapping natural resources on park property by developing a Natural Resource Management Plan (April 9, 2012). The Natural Resource Management Plan identified specific departmental objectives, prioritized data needs, and developed action items to meet two core goals: 1) protect and restore environmental resource assets and 2) enhance the quality of the natural experience for visitors to the parks. The 2013 City of Durham Parks and Recreation Master Plan (Adopted August 19, 2013) further recommends that environmental conservation be a goal of park site development and site renovation.

In April 2012 Stormwater and GIS Services staff met with and Parks and Recreation staff and Brown and Caldwell consultants. An educational campaign was collaboratively developed using the concept of No Mow and Low Mow areas in city parks. A ‘Let it Grow’ video (https://youtu.be/XAmWnQFkDNk) with an accompanying Let It Grow fact sheet (Appendix A) were created to provide information about the concept of allowing some areas to grow naturally instead of being mowed. In September 2012, Stormwater and GIS Services collaborated with the Urban Forestry Division and Keep Durham Beautiful within the General Services Department on a presentation to the Inter-Neighborhood Council about the benefits of riparian buffers.

Stormwater and GIS Services anticipates re-visiting potential areas of collaboration with the Department of Parks and Recreation Department on its next watershed plan. Success of previous public education efforts will be evaluated and new opportunities for collaboration will be explored.

2.3 Department of Water Management

During the field work for the Little Lick Creek WIP in May 2014, field crews observed that in some city utility easements mowing occurred up to the edge of the stream bank. This practice can lead to unstable stream banks and high levels of erosion which can endanger utility lines and increase maintenance costs while degrading water quality. On November 13, 2014, staff from the Department of Water Management, the Department of Public Works, and Wildlands Engineering met to discuss the feasibility of modifying current sanitary sewer easement mowing practices to help restore stream bank vegetation and reduce mowing costs. The Department of Water Management maintains over 300 miles of water and sewer easements, many of which are located along streams. Decreasing the mow width in these

https://youtu.be/XAmWnQFkDNk


areas could shorten mow times, reduce work load, and improve the condition of riparian buffers. A pilot-level assessment was completed to evaluate the feasibility of reduced width mowing in sanitary sewer easements near the stream bank to achieve these benefits.

To identify pilot areas for reduced width mowing, a GIS spatial analysis was used to select 13 candidate sites throughout the city. Sanitary sewers within the City’s municipal corporate limits were assessed to identify easement corridors in close proximity to streams (Appendix B). Aerial imagery and field assessments were used to eliminate sites without adequate space, vegetation, or accessibility. On September 9, 2015 staff from Public Works (Lance Fontaine, Water Quality Analyst) and Water Management (Kenny Willard, Utility Services Supervisor; Erin Harrison, Conservation Specialist) conducted a site visit to review several of the potential locations. The team selected three locations within the City as pilot areas (Table 1).

Table 1. Sanitary sewer outfalls selected as reduced width mowing pilot areas

Site Easement # Easement ID Watershed Pilot Area Length (ft)

1 316 Junction Road Sanitary Sewer Outfall Little Lick Creek 1161

14 570 Kirby St. Sanitary Sewer Outfall Northeast Creek 1770

29 760 Hoover Road Outfall Ellerbe Creek 1830

Total = 4761

Signage for the pilot areas was an important consideration as signs would need to communicate the No Mow limits to maintenance crews while not posing a risk to staff, equipment, or the public. Discussions with Department of Water Management staff and Right-of-Way maintenance crews helped identify important attributes of the signs.

Several sign styles were considered for this pilot study, including:

1. Metal signs fabricated by the City of Durham Sign and Signal Shop 2. Corrugated plastic ‘real estate’ style signs from a sign fabrication company 3. Rhino 3-Rail™ signs by Rhino Marking and Protection Systems

The Rhino 3-Rail™ sign was selected due to the ease of installation, visibility, safety, cost, and customizable graphics. The color of the sign post will be white. Decals to be applied include ‘No Mow Zone’, City of Durham logo, and a QR code that will provide a link to a City of Durham project website that is to include a ‘Let It Grow’ Fact Sheet customized for the project (Appendix A).

The installation of No Mow signs approximately every 100 feet at each pilot area site is anticipated for 2016 to provide a visual indicator for maintenance crews. Department of Water Management has agreed to direct maintenance crews to avoid mowing between the No Mow signs and the stream bank within the three pilot study areas. Department of Water Management staff will continue to remove woody vegetation within the No Mow areas by pruning, cutting, and removal as necessary to prevent establishment of large trees.

Once the pilot study sites are established, Public Works staff anticipates inspection of the easements and the condition of the signs, and will document any potential concerns or issues. Public Works will coordinate with Water Management concerning any issues encountered by maintenance crews as a result of the signs. Adjustments will be made as necessary to the limits of the No Mow area.

Public Works will continue to collaborate with Water Management on this pilot study evaluating the effectiveness of No Mow areas to improve bank stability and water quality in streams adjacent to utility


easements. Based on this evaluation, a determination will be made on the potential to expand no mow areas to other easements.

2.4 General Services Department

Since 2013, Stormwater and GIS Services has been working with Urban Forestry - General Services staff on a contract to manage invasive vegetation in conservation easements located along several stream restoration projects in the City. Stormwater and GIS Services staff and Urban Forestry staff work together to manage the contractor, scheduling, and inspections. Controlling invasive vegetation within these projects is needed in order to preserve the riparian resources and to ensure that the water quality aspects of the stream restoration function properly. Proliferation of these plants can degrade the quality of the wetland and riparian resources in the easement areas, alter their natural condition, and interfere with the ecological functions of the easement areas.

Stormwater and GIS Services and General Services also collaborate through Trees Across Durham. This group was formed in spring 2013 as a Durham County-funded initiative intended for the stewardship of trees in the community. Trees Across Durham is a broad-based partnership dedicated to making Durham a healthier and greener community now and in the future through the planting and protection of trees, the education of tree care-takers and the general public about how to maintain healthy trees, and the measurement and communication of the benefits trees provide to our environment and community. In cooperation with Trees Across Durham, Department of General Services - Urban Forestry Division, and Keep Durham Beautiful, and the Durham City-County Sustainability Office, Public Works has led two Tree Care 101 Workshops. Each workshop is held along the banks of a stream restoration project within one of our City parks. At these engaging events, the public is invited to spend time learning about the critical benefits that native trees and plants provide for our streams, stream buffers, and water quality. Participants have the opportunity to learn hand's-on techniques about tree pruning, planting, and general tree care directly from Alex Johnson, the Urban Forestry Manager and certified arborist. Additional work resulting from Trees Across Durham was the development of an awards program to recognize significant trees in Durham County, promote discovery and ability to identify trees, and help preserve the best examples of specific tree species, particularly natives and those trees well-adapted to Durham County. The program also promotes awareness of trees in our community and hopes to catalog fine examples of magnificent specimens of trees due to their size, setting, historical importance, or significant feature. The Durham’s Finest Trees program was transitioned to the Master Gardeners and launched in Fall 2015.

Watershed planning collaborative efforts between Stormwater and GIS Services and General Services include the previously mentioned joint presentation to the Inter-Neighborhood Council about the benefits of riparian buffers as part of the Northeast/Crooked Creek Watershed Plan. Examination of General Services’ vegetation maintenance practices along riparian buffers may be explored as well.

2.5 Public Works Department

Stormwater and GIS Services within the Department of Public Works leads the City’s Watershed Planning Program efforts and works to implement RAMP recommendations. Beyond watershed planning efforts, various other projects, contract, grants, and initiatives have been used for riparian buffer protection for the past several years. These include a partnership with North Carolina State University (NCSU) on a grant to design, install, and monitor a regenerative stormwater conveyance device on an eroded channel at the Public Works Operations Center within the Third Fork Creek watershed. Construction of the device was completed in November 2014 and it continues to be monitored by NCSU researchers.


Future opportunities for Public Works to implement RAMP recommendations may include:

1. Riparian buffer projects on City Property 2. Coordinating with Project Managers on Capital Improvement Projects 3. Evaluating maintenance practices on City properties with riparian buffers 4. Working with plan reviewers and Development Review Group 5. Collaborating on Infrastructure and Floodplain projects 6. Working with the GIS Group to analyze beneficial spatial data and develop database

resources

Appendix A: No-Mow Fact Sheets for Parks and Sewer Easements

The City of Durham is giving nature a hand by allowing some stream buffers and other less-used areas to return to their natural habitat type. These sustainable, low-maintenance ecosystems allow trees, grasses, shrubs and other plants to filter pollutants in stormwater runoff before it enters a stream. Other benefits of No-Mow practices include:

ECOLOGICAL BENEFITS Encourages establishment of native vegetation Increases biodiversity by providing food and habitat for native animals and plants

Provides shade and cooler water temperatures for fish and aquatic insects

COST SAVINGS BENEFITS Reduces mower maintenance and fuel costs Reduces fertilizer and chemical costs Reduces staff hours spent on mowing Reduces costs of repairing eroded areas of the stream bank

Stream Buffers

WATER QUALITY BENEFITS Naturally infiltrate, slow down, and clean stormwater runoff before it enters a creek

Native trees and shrubs help protect stream banks, reducing erosion and sediment

Native vegetation requires less use of fertilizer, water, and weed killer

EDUCATIONAL BENEFITS Offers places for nature study, public education, and wildlife observation

Provides natural screens and noise control Is a sustainable practice to reduce the City’s carbon footprint

Let It GrowGiving Nature a Hand with No Mow

For information, please contact:

City of Durham Parks and Recreation (919) 560-4355City of Durham Stormwater Services (919) 560-4326

no-mow

F.A.Q.

More information

What do the No-Mow signs mean?No-Mow signs are installed to mark areas where habitat enhancement efforts are in place. The City may limit mowing within marked areas in some parks to encourage the growth of native vegetation. These natural areas provide benefits to water quality and the local ecology, and create cost savings to the City and its residents. No-Mow areas are being evaluated along some streams, lakes, or other places where natural habitat connections make sense for sustainable natural resource management.

Can I still use the No-Mow areas?No-Mow areas are still part of the park and will be open to the public for exploring and learning. To encourage growth of native vegetation, we ask that you respect the plants and animals in these areas. Occasionally these areas may be closed off for planting.

Will other areas of the park continue to be mowed?Yes! Regular maintenance of City Parks remains a priority for the City and will continue outside of the No-Mow areas.

How will No-Mow areas develop over time?These areas will go through a natural process called “ecological succession”. In this process, so called “pioneer plants” establish first. Over time, they are replaced by larger trees that form a shady, open canopy. Sometimes these areas may look brushy or scrubby, but please help us give nature a hand by being patient. Ecological succession can take years to complete but it will help to improve water quality and the health of our City’s streams, lakes, and drinking water supplies by filtering pollutants and reducing erosion. If you have any questions or concerns about these areas, please contact the City.

Frequently Asked Questions

The City of Durham is giving nature a hand by allowing some stream buff ers and other less-used areas to return to their natural habitat type. These sustainable, low-maintenance ecosystems allow trees, grasses, shrubs and other plants to fi lter pollutants in stormwater runoff before it enters a stream. Other benefi ts of No Mow practices include:

ECOLOGICAL BENEFITS Encourages establishment of native vegetation Increases biodiversity by providing food and habitat for native animals and plants

Provides shade and cooler water temperatures for fi sh and aquatic insects

COST SAVINGS BENEFITS Reduces mower maintenance and fuel costs Reduces staff hours spent on mowing Reduces costs of repairing eroded areas of the stream bank

Stream Buff ers

WATER QUALITY BENEFITS Naturally infi ltrate, slow down, and clean stormwater runoff before it enters a creek

Native trees and shrubs help protect stream banks, reducing erosion and sediment

Native vegetation requires less use of fertilizer, water, and weed killer

EDUCATIONAL BENEFITS Off ers places for nature study, public education, and wildlife observation

Provides natural screens and noise control Is a sustainable practice to reduce the City’s carbon footprint

Let It GrowGiving Nature a Hand with No Mow

For information, please contact:

Department of Water Management(919) 560-4381 / [email protected] of Durham Stormwater & GIS Services (919) 560-4326 / [email protected]

Point your smartphone’s QR reader at the QR code,

or enterhttp://durhamnc.gov/1619

into your Web browser’s address bar.

NO MOW

F.A.Q.

More information about other Green Infrastructure practices in Durham:

What do the No Mow signs mean?No Mow signs are installed to mark areas where habitat enhancement eff orts are in place. The City may limit mowing within marked areas along some water and sewer utility lines to encourage the growth of native vegetation. These natural areas provide benefi ts to water quality and the local ecology, and create cost savings to the City and its residents. No Mow areas are being evaluated along some streams, lakes, or other places where natural habitat connections make sense for sustainable natural resource management.

Why are these areas not being mowed? When less area is mowed along a stream bank, plants and shrubs are allowed to grow. Plants, especially native

plants, provide a natural way to protect the stream bank from erosion. This provides multiple benefi ts such as helping water quality in our streams and protecting sewer and water utility lines from damage due to erosion. Regular maintenance of utility lines remains a priority for the City and will continue outside of the No Mow areas.

Where in the City are these No Mow areas? The City’s Water Management and Public Works Departments are working together to fi nd water and sewer utilities

lines where No Mow practices would help the most. At this time, there are No Mow areas along utility corridors in Little Lick Creek, Northeast Creek, and Ellerbe Creek.

Frequently Asked Questions

Appendix B: Pilot Study Areas for Reduced Width Mowing in Sewer Easements

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Facility ID:17832

Facility ID:17831

Facility ID:17830

Facility ID:17593

Little Lick Creek

Little Lick Creek Tributary 1ALittle Lick Creek

Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors, Source: Esri, DigitalGlobe,

GeoEye, i-cubed, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GISUser Community

City of DurhamPublic Works Department101 City Hall PlazaDurham, NC 27701 LLC RAMP

0 300150 Feet

!? Sewer Manholes

Pilot Area for Reduced Width Mowing

Sewer MainsRIVER

STREAM

Durham City Limits

Site #1Pilot Area for Reduced Width Mowing

Easement ID: 304Easement Label: Little Lick Creek Sanitary Sewer OutfallPilot Area Length (Ft): 1161

Site 1

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£¤7098

147

55

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Facility ID:11914

Facility ID:11800

Facility ID:11795

Facility ID:11794

North

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reek N

orth P

rong T

ributa

ry A

Northeas

t Cree

k North

Prong T

ributary

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0 300150 Feet

!? Sewer Manholes

Pilot Area for Reduced Width Mowing

Sewer MainsRIVER

STREAM

Durham City Limits


Easement ID: 570Easement Label: Kirby St. Sanitary Sewer OutfallPilot Area Length (Ft): 1770

Site 14

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£¤70

£¤15/501

147

55

54

751

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Facility ID:16595

Facility ID:16582

Facility ID:16581

Facility ID:16580

Facility ID:16579

Facility ID:16528

Facility ID:16527

Facility ID:16436


0 300150 Feet

!? Sewer Manholes

Sewer MainsPilot Area for Reduced Width Mowing

RIVER

STREAM

Durham City Limits


Easement ID: 760Easement Label: Hoover Road OutfallPilot Area Length (Ft): 1830

Site 29

§̈¦85

§̈¦85

£¤70

147

9855

Documents

Riparian Area Management Plan - Durham, NC