Lake Report

Lake Report

RA’s Management Philosophy

Aquatic plant invasions can sometimes be beautiful but are sometimes unsightly and can affect boat navigation. Managing plant invasions can also be costly.

Reston Association manages our lakes for multiple benefits and it is a delicate balance between ecological health, aesthetics and recreation, and the management actions required for each. We do not manage the lakes for swimming, as this activity is not permitted. We evaluate control methods of aquatic plants — from both a budget and ecological impact standpoint.

Plants of Concern in Reston

Each lake is unique in its plant communities and infestations. At each lake, RA staff monitor for Purple Loosestrife.

Lake Newport

RA began a management plan for controlling white water lilies on Lake Newport which included a treatment on Aug. 28, 2015. Since then, another aquatic plant, Bladderwort, has invaded. Bladderwort is a submerged aquatic plant that floats to the surface forming dense mats. Bladderwort is unique in that it captures its food in tiny bladders, similar to the Venus Fly Trap. There are no health-related issues associated with the existence of this plant on the lake.

In addition to stocking grass carp in mid-November 2015, RA treated half the lake for bladderwort in May and the other half on June 21, 2016. Lake Newport is slated for dredging in 2017, which will deepen the cove areas only.

 

White Water Lily, Nymphaea odorata, is a perennial plant that often forms dense colonies. The leaves arise on flexible stalks from large thick rhizomes that grow in mucky or silty bottom sediments up to 5 feet deep. The leaves are round, bright green, 6 to 12 inches in diameter with a slit about 1/3 the length of the leaf. Leaves usually float on the water’s surface. Flowers arise on separate stalks and have brilliant white petals with yellow centers. The white water lily can spread from seeds or rhizomes.


Lake Thoreau

In 2015, Lake Thoreau was treated to control the growth of Fanwort, Yellow Floating Heart, and Alligator weed, all invasive plants. No treatments are scheduled for 2016.

Fanwort, Cabomba caroliniana is a rooted, mostly submerged aquatic plant with multi-branched leaves.  Small elliptical floating leaves are associated with flowering. Fanwort is capable of rapidly spreading on its own by stem fragments or rhizomes. It creates large floating mats of vegetation which obstruct water traffic and prevent light penetration for growth of native plants.

Yellow Floating Heart is an aggressive plant with green heart-shaped floating leaves and yellow flowers. It is not native to Virginia and was introduced to North America as an ornamental pond species.

Yellow floating heart is an aquatic plant that returns each year and propagates by seeds, fragmentation, and spreading rhizomes. With yellow floating heart, broken leaves with attached stem parts will form new plants. Viable seeds are produced abundantly and germinate readily. Seed hairs help the seeds float and aid their attachment to waterfowl, increasing possibility of spread to new areas.

Alligator weed, a plant native to South America, forms dense mats that crowd out native species and impede recreational activities such as boating and fishing.  Alligator weed was found growing along the dam and shoreline areas near Lakewinds Drive.


Lake Anne

Dredging wrapped up at Lake Anne in December 2015.  RA was able to remove 544 truckloads of sediment from the lake.  The dredge machine also removed 19 bikes and the missing outdoor furniture from Lake Anne Plaza that vandals threw into the lake this summer.

RA treats Lake Anne monthly for blue-green algae control in the summer. Be on the lookout…Water primrose is becoming a regular plant found at Lake Anne.  RA members are encouraged to remove it from shoreline areas by hand pulling.  RA removed the water primrose found along Lake Anne dam last November.


Water primrose is a perennial plant that grows along the shoreline and can form long runners out across the water surface.  It produces yellow flowers and can regrow from seeds and any remaining roots.


Water Quality Report

Reston’s lake water quality is monitored monthly during the summer season.

The latest water quality report discusses the results of the environmental monitoring program conducted from April through September for lakes Anne, Thoreau, Audubon and Newport. The Reston Association has been monitoring water quality in the lakes since 1981.

Lake Newport was added to the monitoring program in 1992. Two additional water bodies were added to the monitoring program in 2003 – Bright and Butler Ponds. The lake monitoring was conducted by Aquatic Environment Consultants, Inc., following procedures established in previous years to ensure the data collection was compatible with previous data. By using similar methods and comparing data, long-term trends can be studied in the water quality of the lakes.

2010 Water Quality Report

2011 Water Quality Report 

2012 Water Quality Report

2013 Water Quality Report

2014 Water Quality Report

2015 Water Quality Report


Invasive Plant Invades Reston Lakes - Purple Loosestrife, Lythrum salicaria

RA is locating, mapping and removing the Purple Loosestrife from Lake Newport and all other lakes to try to eradicate this plant from Reston.

Purple loosestrife is a very aggressive exotic weed introduced from northern Europe during the mid-1800s and is now invading Reston’s lake shorelines. Although attractive while blooming, established plants send up several stalks, each containing 300,000 seeds. If left unchecked, purple loosestrife can take over acres of shoreline, out-competing native plants for growing space.

Reston Association first noticed purple loosestrife on Lake Newport and discovered it on Lake Anne during the National Lake Survey on July 12, 2007. RA would like to remove all of the purple loosestrife that we find along the lakes. We are lucky that there are only small infestations of the plant, which makes it amenable to being pulled by hand, preferably before seeds set. We encourage landowners to grant us permission to remove the plant from private property along the lakes.

If you notice purple loosestrife on Reston Association property or if you have it on your own property and would like us to remove it, please contact Nicki Bellezza at 703-435-6560 or email Nicki@reston.org.

Click here for the Property Access Consent Form.

For a detailed fact sheet on purple loosestrife, please visit:

www.nps.gov

www.invasivespeciesinfo.gov

The information in linked pages is not produced or monitored by Reston Association.  Reston Association is therefore not responsible for the information contained in these linked pages.

Nature Resources