On December 10, 2002 the Chesapeake Bay Local Assistance Board adopted the final amendments to the Bay Act Regulations. Localities have until December 31, 2003 to make changes to their local ordinances to make them consistent with the revised Regulations. One of the more significant changes in the revised Regulations is that the Resource Protection Area (RPA) description was revised to refer to water bodies with perennial flow. RPA lands were previously referred to as lands at, or near, the shoreline. However, "shoreline" was not defined and some interpretation problems arose. Because of changes to other portions of the Regulations, the descriptive term "water bodies with perennial flow" replaced "at or near the shoreline" and, as such, best describes what an RPA is intended to include. Also, the definition of tributary streams, and related language, has been deleted since it was now obsolete.

Section 9 VAC 10-20-105 of the revised Regulations requires that local governments, as part of their plan-of-development review process or during their review of a Water Quality Impact Assessment ensure or confirm that (i) a reliable, site-specific evaluation is conducted to determine whether water bodies on or adjacent to the development site have perennial flow, and (ii) RPA boundaries are adjusted, as necessary, on the site, based on this evaluation of the site. Local governments may accomplish this by either conducting the site evaluations themselves or requiring the person applying to use or develop the site to conduct the evaluation and submit the required information for review.

CBLA recognizes that there are a number of approaches to making evaluations of stream perenniality and will not mandate that any particular method be used exclusively. CBLA has prepared guidance for making distinctions between intermittent and perennial streams. This guidance includes an in-the-field protocol, which will be based largely upon a preponderance of field evidence emphasizing the physical and biological characteristics of the stream channel. CBLA has reviewed and found two field indicator portocols, field tested in Fairfax County, Virginia and the State of North Carolina, to be acceptable for making site-specific determinations. Downloadable copies of these protocols and field evaluation forms are listed below:

• Perennial Stream Field Identification Protocol
  May 2003 (Fairfax County)
• Field Datasheet (Fairfax County)
• North Carolina, Division of Water Quality - Identification Methods for the Origins of Intermittent & Perennial Streams, February 28 , 2005, Version 3.1
• NCDWQ Stream Classification Form
  

(For information on upcoming classes Click Here)

The preferred time for making determinations as to whether a stream contains perennial flow is during the height of the local dry season, which in Virginia is usually between July and early September when normal weather conditions prevail. Thus, if the stream contains water at that time, it will likely contain water at all other times of the year. When it is not possible to survey streams in the dry season, additional corroborative evidence is often necessary. Current weather conditions should be noted since recent or overabuntant rainfall can bias any decision. Preferably stream flow observations should not be within 48 hours after the last rainfall. In turn, drought conditions may cause perennial streams to temporarily run dry with water only standing in pools.

Climate Data: Knowledge of recent precipitation and seasonal climatic conditions is very important in corroborating information collected during field evaluations. The following are links to web sites for current and historic climatic data. Many daily newspapers also provide recent climatic data as well as seasonal information (i.e., month-to-date and year-to-date precipitation).

The National Weather Service in Wakefield, VA includes current and historic data for Richmond, Norfolk, Salisbury, MD and Elizabeth City, NC. Navigate to climate/local data to obtain daily, monthly and historical data. Monthly regional data is also available for a number of other areas in the state at this same web site.

http://mi.nws.noaa.gov/climate/index.php?wfo=akq

Precipitation information can also be obtained from the National Weather Service Office in Sterling, VA provides weather recent and historic data for northern Virginia areas from the following web site:

http://www.weather.gov/climate/index.php?wfo=lwx

National Climatic Data Center Web Site may have a fee involved for accessing/obtaining data (may be free for some governmental entities)

http://lwf.ncdc.noaa.gov/oa/ncdc.html

Upcoming Classes:

For information on the following upcoming classes at North Carolina State University, click on the class that interests you:

Intermittent and Perennial Stream Identification for Regulatory Applications
October 7-10, 2008 - Raleigh and New Bern, NC

www.ncsu.edu/feop/programs.html