 |
|
|
|
|
|
|
|
|
|
 |
 |
||||||||
 |
 |
 |
 |
||||||
 |
 |
 |
 |
 |
 |
 |
 |
 |
|
 |
|
Pennsylvania Handbook of Best Management Practices for Developing Areas§2. How to use the handbook §2.1 Icons The Pennsylvania Handbook of Best Management Practices for Developing Areas is designed to present information to assist in selecting and designing with best management practices (BMPs). The information is derived from a multitude of sources, which are cited in Appendix B, References. The individual BMPs are presented in a format that will enable the user to determine which BMP or group of BMPs is most applicable for a given site. The following information is common to each BMP:
Four icons are used for the BMPs. The icons indicate the primary benefits of each BMP. Although not every icon will appear in each BMP, each BMP will contain at least one icon, which represents the most important reason for using the BMP. If more than one icon appears in a BMP, the order in which they appear refers to the importance of each function in relation to the other functions that the BMP serves. The icons and their respective functions are shown below: Water quality: The icon represents that the BMP described can be used to enhance water quality. Water quality improvements considered pertain primarily to suspended sediment and sediment-bound contaminants, although some BMPs also will be effective in reducing pollution caused by dissolved nutrients, biological oxygen demand, and oil and grease. Water quality BMPs address long-term and chronic water quality problems. Sediment control: The icon represents that the BMP described can be used to control erosion or sediment pollution. Sediment-control BMPs address high-load, short-term, and acute sediment-pollution problems. Runoff peak attenuation: The icon represents that the BMP described can be used to control the peak runoff rate from storm events. Groundwater recharge: The icon represents that the BMP described can be used to recharge groundwater. In the upper right of the first page of each BMP is a list of characteristics that explain the use of the BMP at a glance. The first item is either "Permanent" or "Temporary", which describes the intended performance of the BMP. A permanent BMP is intended to perform for a considerable time, usually for the life of the site’s intended use. A temporary BMP is intended to be used only during the construction of the site. A temporary BMP may be converted to a permanent BMP by adding other elements to the design or by reconfiguring the design, but a temporary BMP should not be constructed with the idea that it will be useful for the life of the projected site use. In general, BMPs will be used in combinations. At the top of the first page of each BMP is a list of "companion" BMPs. These are BMPs that complement or enhance the BMP that is described. Companion BMPs can, when used in conjunction with the BMP described:
The appropriate selection of BMPs for use together in site design will be determined by the size of the tributary drainage area and site-specific characteristics, including imperviousness, slope, and water quality. At the top of the first page, in the same column as the longevity and companion BMP items, is a list of "alternative" BMPs. These are BMPs that can be used instead of the BMP that is described. The alternative BMPs will create some or all of the same benefits of the described BMP. However, alternative BMPs may vary greatly in their complexity, scale, and cost. Throughout the BMP descriptions are references to other BMPs. The references, depending on the information being presented, may be to companion or alternative BMPs, design considerations, or applications of the technology. The cross-referenced BMPs are cited in ALL CAPS so the reader can easily spot their citation. Each BMP is defined in a straightforward manner. The definition clearly describes the type of technology used for the BMP. At the top of each BMP description is a short explanation of the reason for the BMP. The explanation is intended to give the reader a brief glimpse as to the use of the BMP, so the reader can readily decide whether to continue investigating the BMP. The heading "Application" refers to how the BMP can be used and under what conditions the BMP is most applicable. The information can be used to initially evaluate whether a BMP is appropriate for a specific site. §2.9 Recommended Design Criteria The heading "Recommended Design Criteria" is divided into two subcategories: "Requirements for Regulatory Compliance" and "Performance-based Guidelines." Many BMPs are not constrained by regulations. Regulatory requirements that do apply are described so the reader can understand the requirements and take them into consideration when deciding on the appropriate BMP to use. The performance-based guidelines further assist the reader in deciding on the appropriateness of the BMP to the site requirements. §2.10 Operation and Maintenance This section describes the operation and maintenance activities required for the BMP to continue functioning in the expected manner. The maintenance requirements are especially important for the reader to understand because maintenance is many times overlooked or forgotten and yet is critical to the proper functioning of the BMP. The guidelines for operation and maintenance are general in scope and cannot take into account every site-specific circumstance, so the guidelines are supplemented in the supporting appendix material. The "Considerations" section of the BMP description contains information that does not fit neatly under the other headings. The information includes:
As mentioned above, the information for the BMPs comes from a multitude of sources. The most germane of the sources used for each BMP are cited in the "References" section of the BMP. Additional sources that were used for creating and compiling the BMP information are cited in Appendix B, References. §2.13 Specifications and Methodology The last part of each BMP description is the "Specifications and Methodology" section. The section contains technical information, which will be helpful to the designer in determining:
In some cases, technical information developed in other BMP descriptions is referred to. Some design information that is common to several BMPs will be in the appendices and is not duplicated in the BMP descriptions. A checklist for use in preparing construction specifications also is in each BMP description.
|
|
| About PACD | Conservation Districts | News | Events | Products & Services | Resources | Employment |
© 2003 Pennsylvania Association of Conservation Districts, Inc.