Home -- Frequently Asked Questions
Find answers to your questions here. If you don't see your question answered, feel free to look around the rest of the site, visit the Reston Association website, or e-mail the Reston Association directly.
Don't know the definition of a word you see on this page? Check our glossary.
Who do I contact if I have a question or concern regarding this project?
Where can I get information on upcoming public meetings and events regarding this project?
Why is the trail closed? How will I get to where I'm going?
What is the Northern Virginia Stream Restoration Bank?
Why are we creating a stream bank in Reston?
How do we know if the restoration is successful?
Reston has preserved all of its streams, so they should be fine. What gives?
What's wrong with the streams the way they are?
How will stream restoration help our environment?
Is there a difference between urban and rural streams?
Can't we just dredge the sediment out of the ponds once in a while?
Will you get rid of all the beavers?
What are those little silver tags on all the trees?
Who do I contact if I have a question or concern regarding this project?
Contact the Reston Association with questions regarding this project. They are responsible for easements, public meetings, trail maintenance and operation during construction, and other matters. If you have a technical question, they will gladly forward it to Wetland Studies to get it answered or included here.
Where can I get information on upcoming public meetings and events regarding this project?
All public events and meetings are coordinated through the Reston Association. You can visit their website or contact them for the most up-to-date information.
Why is the trail closed? How will I get to where I'm going?
We apologize for any inconvenience, but for safety and liability reasons, trails in the vicinity of the stream work will be closed and blocked off with orange fencing. Signed detour routes will be provided to allow access around the work area. Trail patrons with time constraints should allow for a few extra minutes if they suspect they may be travelling in the vicinity of the work area.
UPDATE: Trails in the vicinity of Reaches 1-3 will be closed between February 12 and April 30.
What is the Northern Virginia Stream Restoration Bank?
The Northern Virginia Stream Restoration Bank (NVSRB) is a partnership between Wetland Studies and Solutions, Inc. and the Reston Association. The NVSRB is responsible for restoring and stabilizing degraded streams in Reston.
First, A Public Works Agency or private landowner needs to impact streams on their property. In the past, they would have had to restore streams as compensation, either on or off their site.
Under the market-oriented system, they can go to a “bank” created by a Bank Sponsor who has obtained credit for restoring impaired streams elsewhere in the same portion of the rivershed & physiographic province.
By purchasing stream credits from the Bank Sponsor, the mitigation requirements of a permit for stream impacts is satisfied. Stream restorers use this pooled money to create much larger, well-designed, & ecologically valuable conservation projects.
HB 2464 was a law written by Wetland Studies and Solutions, Inc., submitted by Patrons Rust and Plum, and signed by the governor in 2005. HB 2464 allows natural stream designs to function as intended by stating that, "Stream restoration and relocation projects that incorporate natural channel design concepts are not man-made channels and shall be exempt from any flow rate capacity and velocity requirements for natural or man-made channels as defined in any regulations promulgated pursuant to this section."
Stormwater regulations, originially intended to regulate concrete or rip-rap stormwater conveyance channels, require designers to contain both the 2-year storm event and the 10-year storm event within the banks of the channels to reduce flooding and damage potential. Physically, this requirement concentrates all of the flow energy of these storms within the channel itself. While concrete channels are strong enough to carry these high flows, natural streams must dissipate that high-flow energy by overtopping their banks more frequently than the 2-year event (let alone the 10-year event). If a natural stream doesn't dissipate some of the energy into the floodplain, soil particles are torn from the stream bank by the high-energy water, causing incision, downcutting, and downstream sedimentation- all of which are issues for Reston's streams.
Why are we creating a stream bank in Reston?
The following are four reasons that it makes sense to build a stream bank in Reston.
1. Degrading streams are located in preserved corridors (without stormwater management) and are mostly controlled by a single entity (Reston Association);
2. Community members are actively involved in protecting local natural resources (i.e. Watershed Plan published in April 2002);
3. The community of Reston includes entire watersheds; and
4. There is a demand for stream mitigation in the region- the Bank service area is determined by HUC and Physiographic Province.
At the completion of Phase I of the project, the Reston Association will have received $400,000, and Friends of Reston will have received $650,000. In addition, Reston will have had its streams, and their assoicated environmental benefit, restored for the benefit of all Reston citizens.
How do we know if the restoration is successful?
WSSI is required to conduct a 10-year monitoring program as part of the Mitigation Banking agreement. During the monitoring period, we will conduct streambed, structure, vegetation, and biological surveys. The purpose of these surveys is to determine if any structure or streambed failure has occured; if the vegetation has established and is thriving; and if wildlife (from bugs to frogs to turtles) has begun to make use of the new habitat. If any of these parameters show signs of failure during the monitoring period, we will return to correct the problem. After 10 years, the project will be turned over to the Reston Association and Friends of Reston for long-term stewardship.
Reston has preserved all of its streams, so they should be fine. What gives?
Preservation and conservation are two very different concepts. Reston's streams are in preserved corridors, but that doesn't stop the excessive flows that run off lawns, streets, driveways, and roofs during rainstorms. Reston was built before the era of modern stormwater management and, as such, allows runoff to flow unchecked into reservoirs like Lake Newport and Lake Audubon. These flows are the cause of Reston's stream degradation.
What's wrong with the streams the way they are?
Reston's streams are showing signs of stress from their urban surroundings. They are incising and their banks are eroding; they are depositing large amounts of sediment into Reston's ponds; and their ecological function has been severely impaired. These factors lead to problems such as disappearing land along the streams, drops in the water table (which affects surrounding forests and lawns), and an inability to sustain a diverse species population.
How will stream restoration help our environment?
The restoration of Reston's streams will involve changes to the streams' pattern, profile, and dimension so that the streams can handle the urban hydrologic regime; the installation of natural, erosion-resistant material on the streambed and energy dissipation measures to help stop erosion on the stream banks due to high velocity flows; and the use of dense vegetation to provide bank stability and habitat for a wide range of species. Combined, these measures will help ensure that Reston's streams return to a natural, healthy, sustainable ecosystem.
Is there a difference between urban and rural streams?
There certainly is a difference between urban and rural streams. Urban streams are subject to the pressures of increased imperviousness in their watersheds, increased pollutant and nutrient loads, and often increased traffic when compared with their rural counterparts. Consequently, they are subject to much higher flow, and much higher bankfull flow, than rural streams. The urban stream responds to these changes through incision or sedimentation, algae blooms and eutrophication, and impaired ecological function. Stream restoration projects can help streams achieve a stable condition even under the pressures of urban life.
Given the site constraints of urban streams, reinforcement of the bed and banks will be necessary. Reinforcement includes rock structures, rock substrate, and heavy planting densities.
Can't we just dredge the sediment out of the ponds once in a while?
Dredging is an expensive, temporary, localized fix only; it doesn't address the root of the problem, which is increased sedimentation due to upstream erosion. Until upstream erosion is addressed (through streambank stabilization or changes in flow regime), Reston's streambanks will continue to slough into the ponds and necessitate periodic dredging.
Will you get rid of all the beavers?
It is not our intention to remove a particular species from the streams; rather, our goal is to create a balanced ecosystem. To do that requires allowing native species to thrive. If, however, an overabundance of a certain species (typically beaver or deer) threatens the health of the overall system, our certified Wildlife Biologist will humanely remove or relocate members of that species.
The design of a stream restoration project is a lengthy process that involves many players, including archeologists, survey crews, ecology specialists, regulatory specialists, engineers, and construction crews. Please see our Design page for an overview.
What are those little silver tags on all the trees?
We are tagging every tree over 4" in diameter (dbh- diameter at breast height) so that we have an accurate picture of the area we're working in and the constraints we need to account for in the design process. Tagging the trees allows us to design the project without worrying about running into snags in the field and helps us to avoid removing valuable trees. To date, we have tagged over 29,000 trees, and we still have more to go.
The tags DO NOT indicate which trees will need to be removed during construction.