CHESAPEAKE BAY PRESERVATION AREA PROGRAM CHESAPEAKE BAY PRESERVATION AREAS

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1 6.1 OVERVIEW CHESAPEAKE BAY PRESERVATION AREAS Virginia s Chesapeake Bay Preservation Area Designation and Management Regulations (9VAC10-20 et seq.) require local governments to implement ordinances designed to protect and restore the quality of perennial streams and their associated non-tidal wetlands, as the conditions in these environments have been determined to directly affect the condition of the Chesapeake Bay. The County of Henrico regulates these environments through development restrictions in these sensitive areas. Chesapeake Bay Preservation Areas include Resource Protection Areas and Resource Management Areas. Development restrictions and requirements in these sensitive environments are described in et seq. of the Code of the County of Henrico. General requirements are included below: 6.2 REQUIREMENTS All Chesapeake Bay Preservation Areas must be clearly identified on the plans in accordance with et seq. and et seq. of the Code of the County of Henrico. Resource Protection Areas include tidal waters, tidal wetlands, perennial streams and their associated wetlands. While the USGS 7.5 minute topographic maps provide information regarding whether a particular stream is perennial (solid blue lines), the County utilizes site specific evidence to determine if a particular stream is perennial. Some of the criteria used to make this determination are included at the end of this section. Resource Management Areas (RMA s) include areas having highly erodible soils, highly permeable soils, steep slopes, nontidal wetlands not included in the RPA, base flood hazard areas, and at least the 100-foot area contiguous to the RPA. We strongly recommend that the environmental inspector be contacted as soon as possible to review flagging of any waters and/or wetlands boundaries and/or Resource Protection Area boundaries. Final plans must reflect all such boundaries. The location of orange safety fence or non-tearable yellow and black barricade tape, silt fence for protection of the Resource Protection Area and wetlands areas and for the clearing limits adjacent to those areas must be shown on the plans. Plans will not be distributed at the pre-construction meeting if the appropriate type of fencing and/or flagging are not in place at the site. Additional Requirements for Residential Subdivisions On all construction plans, lots that contain Resource Protection Areas must be identified with a single asterisk (*) and the note listed in italics below. 6-1

2 Lots marked with an * have limitations for dwelling shape, size, and location. If a lot contains a RPA or RPA buffer, these areas are to remain undisturbed and are to be protected from all construction or land disturbing activities. On all record plats, lots that contain Resource Protection Areas must be identified with a single asterisk (*) and the note listed in italics below. Lots marked with an * have limitations for dwelling shape, size, and location. If a lot contains a RPA or RPA buffer, these areas are to remain undisturbed and are to be protected from all construction or land disturbing activities. See construction plans on file in the Planning Office for additional details. There must be a minimum buffer equal to the rear yard setback established by the Planning Department between the Resource Protection Area buffer boundary in the rear yard and the buildable area. There is a 25-foot minimum buffer between the buildable area and the Resource Protection Area buffer boundary located within or adjacent to the side yard. Environmental Protection Area signs are required to be installed along the boundary of the Resource Protection Area within residential subdivisions prior to the preconstruction meeting in accordance with MS 9.13 found in Chapter 9 of this Manual. These signs must be in place prior to distribution of the plans at the pre-construction meeting. 6.3 WAIVERS AND EXCEPTION REQUESTS All requests for exceptions or waivers must be made in writing to the Director of the Department of Public Works and submitted to the project review engineer. It will be the review engineer s responsibility to coordinate all requests. It is our goal to have all requests responded to within 12 working days of receipt of the applicant s letter. It must be stated with your request if you are requesting an exception from the Chesapeake Bay Act or NPDES. It must also state the specific reason for the exception request (i.e., Resource Protection Area (RPA) buffer reduction). Exceptions may be granted provided that exceptions to the requirements are the minimum necessary to afford relief, and reasonable and appropriate conditions upon any exception granted are imposed as necessary, so that the purpose and intent of the Act are preserved. Prior to granting any exception the Director of Public Works/County Engineer shall find that: 1. Strict application of the requirements would produce an undue hardship; 2. The hardship is not shared generally by other properties in the same vicinity; 6-2

3 3. The authorization of such exception will not be of substantial detriment to adjacent property and that the character of the zoning district will not be changed; 4. The project complies with all other County requirements; and 5. Water quality shall be preserved to the maximum extent practicable. Your exception request must demonstrate in writing what the undue hardship is, and that all other conditions have been met. Please note, cost is generally an issue shared by others and would not qualify as a hardship under #1 and #2. RPA Buffer Exceptions In all cases where an exception is requested for an encroachment into the RPA, a water quality impact assessment, as defined in et seq. of the Code of the County of Henrico, must be submitted. On lots recorded prior to October 1, 1989, modification to the buffer area width may be allowed by the Director of the Department of Public Works/County Engineer in accordance with the following criteria: 1. Modifications to the buffer area shall be the minimum necessary to achieve a reasonable buildable area for the principal structure and necessary utilities. 2. Where possible, an area equal to the area encroaching the buffer must be established elsewhere on the lot to maximize water quality protection. 3. In no case shall the remaining portion of the buffer be less than 50 feet in width. Lots recorded between October 1, 1989 and November 15, 1991 are eligible for transitional exceptions. (see of the Code of the County of Henrico) On lots recorded after November 15, 1991 an exception will be required for any proposed buffer reduction (excluding BMP s). An exception will be granted only if the buffer requirements would produce an undue hardship (see previous hardship comments). Again, the exception request must clearly demonstrate the undue hardship. For any proposed BMP which is to be located in the landward (upper) 50 feet of the buffer, it must be demonstrated that locating a BMP in the buffer is the best, or perhaps, only solution based on topographic or soil limitations. All buffer reductions must be the minimum amount necessary to site the BMP. Waivers The Director of the Department of Public Works/County Engineer may waive or modify the requirements for additions, modifications or alterations to existing structures in RPAs provided that; 6-3

4 1. There will be not net increase in nonpoint pollutant loads; and 2. Any development or land disturbance of 2,500 square feet or more complies with the erosion and sediment control requirements of et seq. of the Code of the County of Henrico; and 3. Additions shall be built outside RPA s where possible. 6.4 RESOURCE PROTECTION AREA DETERMINATION FIELD PROCEDURES FOR PERENNIAL STREAM DETERMINATIONS The following criteria should be examined in the field on a site-by-site basis to determine whether a particular stream reach has perennial or intermittent stream flow. 1. STREAMFLOW Presence or absence of flowing water dependent upon antecedent moisture conditions. 2. CHANNEL GEOMETRY Perennial systems exhibit a defined and consistent geometric shape. Channel parameters include bank height, channel width, bank slope, and channel slope. 3. STREAMBED SOILS Perennial streams Absence of characteristics associated with a fluctuating water table (i.e., iron redox-concentrations and oxidized rhizoshperes). Sandy soils contain a relatively equal distribution of organics throughout the soil profile. Presence of gravel and/or cobbles with little or no silts or clays associated with the surface soils. Intermittent streams Presence of characteristics associated with a fluctuating water table (i.e., iron redox concentrations and oxidized rhizospheres), particularly iron-redox concentrations. Mineral soils with matrix and mottles of contrasting color, chroma variable, often > 1. Organics not evenly distributed throughout the matrix of sandy soils and/or organic streaking evident in the surface horizon. Presence of organic pan (i.e., accumulation of organic materials in bed layers) suggesting absence of flow during some period of the year. 6-4

5 4. VEGETATION Perennial streams In lower energy systems (i.e., bottomlands or areas situated just above tidal influence), presence of species with a submerged-aquatic or floating leavedaquatic life history strategies. In higher energy systems, a general absence of rooted vegetation. Intermittent drainage system Presence of annuals or emergent perennials that require exposure (no inundation) at some point during the growing season. 5. BENTHIC MACROINVERTEBRATES Presence of species that have an aquatic life cycle of greater than one year. Species identification generally completed by a qualified aquatic ecologist. 6. VERTEBRATES In general, the presence of fish. 7. OFFSITE RESOURCES Discussions with long-term residents and local professionals Personal communications with local professionals that include hydrologists, county agents, Natural Resource Conservation Service (NRCS) technicians, surveyors, foresters, and field engineers. Review of aerial photographs. RPA WETLAND DETERMINATIONS Nontidal wetlands connected by surface flow and contiguous to tidal wetlands or water bodies with perennial flow are included as Resource Protection Area features. In order for these wetlands to be included as Resource Protection Area features, the must rely primarily on the tidal or perennial stream and/or waterbody to supply their main source of wetland hydrology. In making this determination, the question should be asked if this wetland would be present in this location if the tidal or perennial waterbody was removed from the landscape. If the wetland would cease to be present in this situation, it should be included as an RPA feature. 6-5