October 2017 LMIP

ISSUE:  Lakes Management Implementation Plan Update.
RECOMMENDATION:  Management recommends the Board continue to provide input and directions on the Lake Management Implementation Plan.
BACKGROUND:  In 2012, the Board initiated a restoration plan to improve the health of the Lakes. The Board approves the Lakes Management Implementation Plan annually in January. Each month the Board is updated on the progress on Lakes Management. Additionally, the Board conducts a semiā€‘annual review in April and October in order to present the progress of implementation to the Community.
 
A. Works Completed to Date-  
  1. Structural Projects- Flat Run Forebay design was completed by Stantec. After design completion, additional utilities were discovered in the construction area. 14th Pond Design request for proposal was released September 11, 2017.
  2. Public Education- Lake Currents - Articles were written for the Lake Currents newsletter in subjects of prevention of transfer of aquatic invasive species and leaf removal. An information booth was utilized and pamphlets on aquatic invasive species were distributed at the LOW Independence Day festival. Poster sized informational signs for aquatic invasive species were used.
  3. Dredging- The dredge is presently operating on Keaton’s Lake. Lake sediment dredging has been completed in coves K1, K2, K4, & K5 since the last semi-annual review in April. 1,344 cubic yards of sediment were removed from these coves.
  1. Roadside Ditch Reconstruction Program- LOWA Roads Crew’s work combined with work of annual contractors yield the following results:

 
  1. Water Quality- LOWA staff have completed all annual, quarterly, and monthly water quality testing in 2017, including nutrient monitoring, physico-chemical monitoring, petroleum monitoring, heavy metals monitoring and bacteriological monitoring.
  2. Aquatic Plant Management- Preliminary Spring Vegetation survey work was completed in May to identify any potential problem areas. Fall Vegetation Survey field work was completed in September and October by the Environmental Resources Manager with diving assistance from Security Chief Scott Walker, and Officer Walker.

B. Works in Progress-
  1. Structural Projects-
  • Flat Run Forebay – Due to site specific construction constraints related to the Rapidan Service Authority water and sewer utilities in the project area, Flat Run Forebay construction is on hold as alternate avenues to complete the project are being explored.
    • Recommended – Request utility movement (bury water and sewer lines deeper, below project area) by Rapidan Service Authority; if cooperative acquire utility relocation fee. If possible and cost effective, proceed with construction of completed Flat Run Forebay design, which has already received preliminary approval from the U.S. Army Corps of Engineers, after utilities are relocated.
    • Purchase a plot of land along Flat Run from Flat Run Farm property owner, if owner is willing to sell at a cost effective price. If acquired, release a request for proposal for Design work for an offline sediment trap structure, similar to Eastover Park Water Quality Retrofit. Select design firm, design structure, acquire permits (U.S. Army Corp of Engineers, Orange County, etc., ) and then release a request for proposal for construction. Select construction firm and build structure.
    • Relocate back gate, and use back gate lane area to construct a sediment and nutrient catching, best management practice structure. Utilities and shallow bedrock are likely concerns in this area (additional utilities survey and geotechnical exploratory work required for estimating potential sediment and nutrient removal rates of potential structures that could be built in this area without also having to move utilities) If back gate is relocated and area becomes available for construction, release a request for proposal for Design work. Select design firm, design structure, acquire permits (U.S. Army Corp of Engineers, Orange County, etc.,) and then release a request for proposal for construction. Select construction firm and build structure.
  • 14th Pond Forebay – Request for proposal for design work was released September 11th. Design Firm proposals were due October 11th, and interviews will be conducted by LOWA staff October 27th. Design contract will be awarded November 4th.
 
  1. Roadside Ditch Reconstruction- Contractor Finish Line Environmental completed two miles of roadside ditch reconstruction in September-October 2017. Ditch reconstruction occurred in select ditches on Harrison Circle, Cavalier Court, Stratford Circle, Mason Street, Clover Hill Court, Battlefield Road, Confederate Drive, Butler Circle, and Lakeview Parkway.
  2. Public Education- Environmental articles will continue to be written for the Lake Currents newspaper; continue to promote local resources and organizations for members to utilize.
  3. Grant Funding- Additional grants will continue to be sought and applied for to aid in the funding of projects.
  4. Dredging- Dredging operations will continue in scheduled coves in Keaton’s Lake through October. After completion of scheduled coves on Keaton’s Lake, equipment examination and routine maintenance will occur for the dredge, barge, clam truck, and dump truck. Upon completion of routine maintenance, dredging operations will be moved to the Main Lake. The Main Lake dredging cycle is two years.
  5. Water Quality- LOWA staff will conduct annual, quarterly, and monthly water quality testing throughout the remainder of the 2017/2018 fiscal year.
  6. Fisheries/ Habitat Management- 2,000 Blue Gill & Redear Sunfish and 250 pounds of forage minnows were stocked in Keaton’s Lake. 3,000 Blue Gill & Redear Sunfish and 650 pounds of forage minnows were stocked in the Main Lake. Stocking occurred the last week of April.
  7. Aquatic Plant Management- Field work for the Fall Vegetation survey was completed in September/October. The Environmental Resources Manager is currently working on the 2017 Vegetation Survey Report.
 
 
 
C. State of the Lakes-
The following is a brief overview of the health of the lakes as indicated from water quality data collected from 2017.
The Main Lake and Keaton’s Lake consistently score poorer than EPA water quality standards for Total Nitrogen and Total Phosphorous. This is an ongoing concern.
  1. Main Lake- Over the past three years, Total Nitrogen has been higher than the recommended level by the EPA. The Main Lake has averaged approximately 2.5 times the EPA standard. This is not a good thing. Over the past three years, Total Phosphorous has also been higher than the recommended level by the EPA. The Main Lake has averaged approximately 3 times the EPA standard. This also, is not a good thing.
  2. Keaton’s Lake- Over the past three years, Total Nitrogen has been higher than the recommended level by the EPA. Keaton’s Lake has averaged approximately 3 times the EPA standard. This is not a good thing. Over the past three years, Total Phosphorous has also been higher than the recommended level by the EPA. Keaton’s Lake has averaged approximately 3 times the EPA standard. This also, is not a good thing. However, 2017 Total Phosphorous results for Keaton’s Lake are healthier than comparative 2016 Total Phosphorous results.
Over the past 3 years, Chlorophyll-a results in both Lakes remain below recommended state threshold levels. There is no reason for concern of Chlorophyll-a levels.
Further improvement of water quality results can be achieved through construction of additional sediment & nutrient removing structural projects, and public education. Public education in the areas of restricted nutrient fertilizers, and leaves/pet waste as excessive nutrient runoff in ditches to the Lakes will continue to be emphasized.

c. Nutrient Levels: (Phosphorus, Nitrogen, & Chlorophyll-α)
 
ML- Average Total Nitrogen Concentrations
  
ML- Average Phosphorus Concentrations

KL- Average Total Nitrogen Concentrations 
                                                                                                                                                                                              
KL- Average Phosphorus Concentrations
 
  ML & KL- Chlorophyll-α

 

 
 
Physical Properties

 
 
  • pH: Within the standards for aquatic life.
  • Dissolved Oxygen: DO levels fluctuate in both lakes as water temperatures change seasonally. DO is at acceptable levels in both Lakes.
  • Temp: Both Lakes are within the acceptable level.
  • Secchi Depth: Main Lake is well within the standard.  Keaton’s Lake water clarity has continued to improve on average over the past 3 years.  
  • Conductivity: Acceptable level for both lakes. General standard for lakes is 50-1500µS/cm. (2014, Teton Science)
  • Turbidity & TSS: Acceptable level for both lakes.  General standard for turbidity is 10-50 NTU (2004, EPA.)  Keaton’s Lake has higher levels on average than the Main Lake; this is expected given the low Secchi Depth readings on Keaton’s Lake.
  • The dark line separating 8/14/2014 and 11/4/2014, marks the completion of the 13th Fairway Stream Restoration Project. The dark line separating 12/19/2016 and 5/10/2017, marks the completion of Eastover Park Water Quality Retrofit. Total suspended sediment results, and turbidity results are both lower on average (desirable), since completion of projects. Secchi Depth results have increased on average (desirable) since completion of projects. (Clearer, less turbid water)
Posted: 3/22/2018 3:41:13 PM by Bobby Jones | with 0 comments