Sensitive Area Study

The Parks Operations Division is currently in the process of adjusting maintenance practices to better manage sensitive areas in City parks. Salem is one of the few cities to implement such an in-depth sensitive area process.

Listed below is information that was part of a comprehensive study to develop a management practice handbook to best serve sensitive areas. The information was shared at Salem Watershed Council meetings and with other interested parties. After the review process, Park supervisors and field staff have been given a reference handbook that includes maps to better delineate and adjust practices in sensitive areas. Any questions regarding this study can be directed to Parks Operations Division at 503-588-6336.

Introduction

As cities continue to grow in both population and area, effects on the natural world increase dramatically. Environmental degradation can be caused by many aspects of urban growth and development, including park development and management. The City of Salem Parks Operations Division intends to address some of these concerns through the sensitive area study and the subsequent management of parks that will result from the study.

Purpose

The management practice handbook created for Park staff is designed to limit the potential impact that park design, use, and management has on environmentally sensitive areas within and adjacent to city parks. The handbook is the result of a study of the city parks which was undertaken in response to new Endangered Species Act (ESA) listings, Clean Water Act (CWA) regulations of wetlands and an understanding of the need to protect critical aspects of the environment.

The primary goals of the sensitive study were:

• Identify areas within city parks that have special environmental or historical sensitivities.
• Identify park areas and management practices that may negatively affect the identified sensitive areas.
• Develop an initial list of Best Management Practices (BMPs) to minimize potential negative effects of park use and management.
• Prepare a useful management practice handbook to guide park employees on how to maintain each park based on the sensitive area limitations.

The management practice handbook maps sensitive areas and features and lists BMPs that can be used to minimize potential impacts. Best management practices and restrictions used in this handbook are not designed to address specific environmental regulations, but are viewed as first steps toward addressing concerns resulting from current and future environmental regulations. The administration staff may make exceptions the sensitive area BMPs on a case by case basis as long as the exception is deemed necessary and efforts are taken to minimize potential negative effects that might be caused by the exception.

Methodology

The first step was to collect and review information that could help with the design and implementation of this project. Background information on subjects such as pertinent environmental regulations, current BMPs, and mitigation options were collected and reviewed. This information was used to define the structure of the study and to identify potential sensitive features that could be affected by park management.

The sensitive area definitions and BMPs were developed on a park system scale in order to provide consistency. Different types of sensitive features, such as waterways, creeks, or Oregon White Oak groves were identified and delineated using site visits, research, and information gathered from meetings and personal contacts. A list of high impact areas and potentially damaging management practices was derived from park task lists and other information provided by district supervisors. Best management practices and restrictions were assigned to the areas and were reviewed by management and the Sensitive Area Study Steering Committee.

The key features and sensitive areas of each park were mapped in the field using a Global Positioning System (GPS). The field data was combined with information derived from digital ortho-photographs and existing Geographic Information System files to create park base maps. Areas within each park were identified and color coded based on their sensitivity. As a default condition, when two sensitive areas overlap, the more sensitive area's BMPs take precedence. For example, if part of an Oregon White Oak Grove is located within a riparian management zone, the overlapping portion of the oak grove is treated with the more stringent restrictions of the riparian management zone. Separate tables listing sensitive area and high impact areas were created for each park, allowing for variations in BMPs where needed. A table listing conflicts between current practices and suggested practices was also included. The final park details and maps were reviewed by park administration and operational staff. All comments were reviewed and considered before final edits were made. The result is this handbook which is intended to minimize harmful effects on the environment by enabling thoughtful planning, design, and management.

The Need for a Sensitive Study

Several potentially harmful management practices are necessary to maintain a park for intended uses. For example, turf areas require mowing, irrigation, and fertilization to maintain the optimal turf health needed to withstand heavy use, but any or all of these actions could have a negative effect on adjacent sensitive areas. It is necessary to the overall health of the environment to implement these horticultural practices in such a way to minimize their potential negative effects. This can range from changing fertilizer and irrigation amounts to restoring an area back to its natural state. The degree of action used depends on the sensitive feature and the needs of park users.

Protection of Native Species

Throughout history, humans have knowingly and unknowingly dispersed plant and animal species far beyond their natural range. Some of these exotic species are more aggressive than the native species and become highly invasive. As invasive plants spread they compete for the same resources as native plants which can then decline. Park management should provide for the control of invasive plants as well as the culture and protection of native plants.

While all native species have some value, certain plants are of special interest due to their rarity, stature or other intrinsic value. Two native Oregon trees that tend to grow in groves and have a special value are the Douglas-fir and the Oregon White Oak. While neither tree is threatened, they are both worthy of preservation. The Douglas-fir (Pseudotsuga menziesii) is the state tree of Oregon and the number one wood producer for the country. It ranges from California to Alaska and to parts of the Rocky Mountains. Douglas-fir often grows in dense stands and a mature specimen may be more than 200 feet tall. Citizens of Salem are privileged to have several healthy stands of Douglas-fir within their park system.

The Oregon White Oak (Quercus garryana) has a slightly smaller natural range. Though it can be found from southern California to British Columbia, it is most common in the Willamette Valley. Oregon White Oaks are not shade tolerant and can often be shaded out by taller pines, firs, and big leaf maples. Historically large groves were maintained through fires that burned through the valley and killed competing trees before they could shade out the oaks. These fires were both naturally occurring and set purposefully by native cultures. As the European culture replaced the indigenous peoples, fire suppression caused many oak groves to become overgrown. Salem's Oregon White Oak groves should be managed to maintain their health and limit the effects of competing species. In addition to trees, several species of wildflowers and other native plants require special management strategies.

Endangered Species Act

Some species are afforded additional protection through the Endangered Species Act (ESA). These are species of plants and animals that have been listed as threatened or endangered. Two species of fish are of concern for Parks Operations: Spring Chinook Salmon (Oncoryhncus Tshawytscha) and Winter Steelhead (Oncoryhncus mykiss). Both of these listed fish may be found in certain streams flowing through Salem. The National Marine Fisheries Service (NMFS) is the federal agency in charge of regulating the ESA for these fish. Private citizens, companies, and governments are required to minimize their effects on these fish and the waters in which they live. Park uses and management practices should be planned to minimize potential harmful effects caused by the introduction of chemicals, soil erosion, or changes in the nature and amount of natural debris that has historically entered the riparian system. Furthermore, creek banks and associated riparian zones should be managed to promote the historical attributes of the creek, including shade, water temperature, accretion of natural materials in the cannel and riparian corridor, and high-quality fish habitats. A major BMP proposed from this study is the creation of riparian management zones to maintain healthy fish habitats. The base widths for riparian management zones along salmon bearing streams are set at 150 feet, based on recent NMFS biological opinions. The management zones and other BMPs resulting from this study will reduce potential negative affects on these fish and their habitat.

Wetlands

The wetland ecosystem is a unique environment for aquatic and terrestrial species. The Division of State Lands (DSL) is in charge of identifying and delineating jurisdictional wetlands. Jurisdictional wetlands are protected from dredge and fill activities through the Clean Water Act (CWA), which is administered in Oregon by DSL. While several of the parks have wetlands, not all have been officially delineated or listed on Salem's Local Wetland Inventory (LWI). Even so all wetlands should be considered for protection as they provide a variety of beneficial functions such as fish habitat, water purification, flood water retention, and as a source of water to creeks during times of low rainfall. Creating a special management zone around wetlands can help reduce the effects of park activities such as fertilizer application and irrigation, which can lower the water quality.

Water Quality

Park use and management have the potential to degrade the water quality of nearby wetlands, creeks, and ground water. The two major management practices that degrade water quality are irrigation and the application of chemicals. Nutrients from fertilizers can enter waterways through surface and subsurface flows. In addition to potentially decreasing the water quality for human use or consumption, increased nutrient levels within a watercourse may enable excessive algae growth and eventual die-off which reduce the amount of available oxygen for invertebrates, fish, and other aquatic life. Herbicides can negatively affect the biological balance by killing off aquatic vegetation. Excessive chemical application or excessive watering has the potential to increase the amount of chemical runoff that reaches a creek. By applying the minimal amount of a chemical needed and not over-watering, the amount of chemicals reaching a creek can be minimized or eliminated. The potential for chemical runoff can be further reduced through restrictions on the use of chemicals near waterways and catch basins. Encouraging vegetation growth within riparian management zones has been shown to further remove excessive nutrients before they reach a creek or wetland.

Excessive watering can increase the rate at which water and chemicals enter nearby waterways and ground water. Parks Operations is currently using a computerized MAXICOM irrigation system at several parks and is continuing to expand the system. MAXICOM greatly reduces the amount of excess water used by matching the irrigation rate with the evapotranspiration rate. This is an extremely beneficial first step for preserving water supplies and quality, and its use should continue to be expanded and adjusted to meet the requirements of turf areas with a minimum impact on sensitive areas.

Historical Features

The City of Salem parks has several key historical features such as Deepwood Estate, Pioneer Cemetery, Bush House and Rose Garden, and the Giant Sequoia (Sequoiadendron giganteum) in Waldo Park. BMPs should be designed to have minimal harmful effects on features of historical importance, just as with environmentally sensitive areas. This study did not delve into specific BMPs for historical areas; the general recommendation for historical features is to maintain them in such a manner as to preserve and enhance their historical values.

Conclusions and Results

This study has produced sensitive area maps and initial BMPs for each park. Several of the parks such as Aldrich, Richmond, and McRae were found to have no or very minor sensitive areas. Management practices will not be greatly affected in these parks. Many of the parks have significant sensitive features which have special management needs. Initial BMPs have been established for these areas. Many of the BMPs for the sensitive areas require change from current management practices. Some of these changes may be as small has changing mowing schedules or as large as developing a riparian restoration and management plan.

This study will allow staff to identify areas of conflict and respond according to the identified BMP's. In some cases, there may be a need to implement a mitigation strategy if permanent structures, such as buildings or walkways have been placed to close to a sensitive area.

This plan also allows volunteers an opportunity to become involved in the sensitive areas. Brush College Park is a prime example of this occurrence. Park Partners have planted native plant material near the bank of Glenn Creek to act as a buffer. When mowing in the area, Park staff leave an appropriate distance between the native plants and the area they mow. Students from Waldo Middle School are currently involved with projects at the creeks in McKay School Park and Livingston Park. Their goal is to enhance the waterways and eliminate the invasive canary reeds that have overtaken the creeks.

The sensitive area study also assists in budgetary decisions for Park Administrators. The financial needs associated with the study can be a guide and addressed as budgets are prepared.