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Sediment Escape in
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Halfway measures - New straw bales and some mud removed from pond, but slope is left to deteriorate The Franconia District office advises that the geotechnical report has been accepted and approved. Hooray! At last! Yet we are also advised a multistep multi-agency process still lies ahead, involving a rough grading plan, structural plans, and conservation escrow. This is estimated to take another 5 long months, at what is called an "expedited review".
Some upgrades to the temporary measures were done in January - scooping some of the mud to one side and installing fresh walls of hay bales. Yet the slope itself was left in its degraded state. The continued deterioration of the temporary repairs on the slope have now seen the protective fabric peel away in large areas, leaving the bare soil underneath to erode further with every rain.
Status Update: How is it possible that fully four and one-half years after we first reported this issue, it is still unresolved? The drainage pipe on this slope alongside the entrance to Lake Accotink Park failed in 2019. Since then, we have seen unconscionable inaction, half measures, and repeated repair failures. How hard can this be? The latest measures were strictly temporary fixes, but have been left unchanged for at least 10 months. Now the inadequacy and failure are obvious:
It is an eyesore to see this at the main entrance to Lake Accotink Park, a jewel of our park system.
It is a disgrace that this source of sediment contamination goes unchecked while the future of Lake Accotink itself is threatened by filling with excess erosion sediment, just like this pond.
Temporary fix is holding - but when will a permanent solution appear? Effective emergency repairs seem to have stabilized the slope - for now. Rock vanes now guide and slow the energy of the stormwater flow. Geotextile protects the slope from eroding. Hay bales guide the runoff away from the street and pond and provide some filtration.
So at least the most urgent issues have been mitigated. Yet this was done back in June. Nothing more seems to have happened since. The current structure will not last indefinitely. Nor is it acceptable that this eyesore is allowed to exist at the main entrance to Lake Accotink Park, putting a thumb in the eye of all the watershed preservation goals of Fairfax County.
We missed getting video during the heavier rain today, but a neighbor provided this description "it was just a waterfall gushing down the hill and washing a lot of the exposed soil into the gutter and down a nearby drain"
Update (excerpt) from Lee District Supervisor's Office:
Response (excerpt) from Land Development Services: One of our Senior Engineering Inspectors has been assigned to this project. A flush-vac truck was mobilized to the site today to remove a portion of the sediment, and it is planned to be mobilized tomorrow as well. This is at least the third time flush-vac trucks have been mobilized to the site in the past two months.
There were challenges in getting materials which has delayed the construction. Considering the current site condition, we have requested the engineer to provide a plan for Emergency Erosion and Sedimentation control measures. The emergency plan is to be received by our office this week. In addition, staff are in the process of issuing violations for the site.
Status Update:
The canyon just keeps growing. Delay only makes solutions more difficult and the harm worse. 
Improvement? Problem is half-solved, but now the solution is the problem. Status Update: After months of construction on repairs to the failed drain pipe in the farm pond (FM0495), we are left scratching our heads at the results so far. The photo shows the current status, with the repair already failing, the slope denuded of trees, and the pond still half-filled with mud. The design of the repair seems to have been questionable to begin with. Could an open unreinforced channel ever have been expected to maintain integrity on this steep slope? Fairfax County Land Development Services is talking with the property owner to seek a solution. How many more months and years will the situation continue to deteriorate until an effective solution is in place?
On a positive note, open water still remains in the southern half of the pond, providing some breeding habitat for amphibians and sheltering a few turtles.
Status Update: Over a year since Stormwater Planning Division issued a Corrective Action Notice, we are advised work is to begin in the next week on repair to the failed drain pipe and excavation of the sediment in the farm pond (FM0495). Of course, this work will exactly coincide with the amphibian breeding season, with unknown consequences for amphibians attempting to reproduce in the remnant of the pond that still retains open water.
As the parties to this fiasco dithered, the chasm in the slope continued to grow, and has now claimed a manhole standpipe at the very top of the slope. Any further erosion could cause the catastrophic failure of the pond at the top of the slope (DP0353). It doesn't require much imagination to know that if this sediment were filling a parking lot instead of a pond, action would have been taken within days, not years.
The growing chasm has claimed a manhole standpipe at the top of the slope. 
November 15, 2020 - Sediment delta has nearly obliterated the vernal pool Status Report From Inspectors: (After refiling the complaint online January 20, 2020, and a followup email March 21, 2020) On 2/26/2020, Stormwater Planning Division issued a Corrective Action Notice to the President & CEO of WTG Properties, about sediment from the farm pond (FM0495) on his property, overflowing and entering a Fairfax County Park Authority storm drain curb inlet. A private stormwater pipe has ruptured above the farm pond (FM0495), causing acute erosion of sediment discharging into the farm pond. The farm pond's discharge culvert is clogged or broken, causing sediment during rain events to discharge onto Lake Accotink Access Road and into the curb inlet which discharges into Accotink Creek. The Stormwater Pollution Inspection Team has been working with Park Authority staff to ensure the illicit discharging is eliminated. The owner of the farm pond (FM0495) has hired a contactor to repair the stormwater pipes in order for the farm pond to function properly, to eliminate any illicit discharges. A Land Development Services permit will likely be needed, as the area will be over 2500 ft2. The Park Authority will be involved in plans as they are downstream and their parking lot will be needed for staging. Work may finish by summer. Stormwater Planning Division will keep an eye on ensuring that the contractor tries to limit the damage to the habitat, looks out for amphibian breeding at the pond, and ensures no pollution enters stormwater structures or any waters. Call to action by Save Lake Accotink 
Large sediment delta visible in vernal pool The real concern is not inside the detention basin. It’s the outfall pipe that has failed, and the heavy woody vegetation on the dam face. Fortunately, this is not a wet pond but it’s probably meant to hold more water than it does now. The ‘normal’ water elevation reads pretty clearly in the photos. Pictures here illustrate:
--- March 14, 2019 Official Response: Sediment complaint Dry Pond discharge into vernal pool
In response to the Friends of Accotink Creek complaint, today I walked around the private dry pond DP0353 behind Cox Communications at 7741 Southern Drive Springfield, VA 22150. I saw no obvious pollutants from Cox Communications facility entering the dry pond. The dry pond has no vegetation and has a large amount of sediment build-up in it. The sediment appears to be discharging into the vernal pool (on GIS map farm pond FM0495) on Lake Accotink Access Rd.
I think this is an Maintenance and Stormwater Management Division private dry pond inspection issue.
Initial Report - Vernal pool sediment pollution incident at Lake Accotink Park I was out checking some vernal pools at Lake Accotink Park today, it was sad to find this.... This afternoon, during a watershed walk, we observed a vernal pool that was severely contaminated with sediment. Instead of its usual dark, black color, the pool was orange-green, indicating large levels of suspended sediment, and possibly algae associated with a nutrient influx, and there was a layer of sediment residue on the leaves along the edge of the pool. We had just observed several flourishing vernal pools further downstream, with large numbers of active wood frogs and egg masses in clear water. This pollution event has likely wiped out any possibility of supporting vernal pool obligates in this pool this year. There was an obvious delta of fresh sediment at the base of a metal outfall pipe coming down the slope and draining into the pool. Closer observation showed that there had been a blowout, likely due to a failure of the pipe, scouring out large amounts of sediment around the pipe, and causing several trees to collapse. This was clearly the source of the sediment pollution. The blowout had created a large cave-like hole in the slope, with water still dripping out of the pipe. We went to the top of the slope and found a large stormwater pond, apparently connected to the property at 7741 Southern Drive, which looks like a Cox Communications facility. There is a large parking lot and several buildings draining to that stormwater pond. The pond looked like it was a "wet" pond, but it had no water in it despite the recent rains. We surmised that the outlet pipe had failed, and so instead of retaining water during rain events, water was flowing through, damaging the outfall pipe, and causing the sediment pollution of the vernal pool.
I've reported this event to DEQ and DPWES using the contact information at Friends of Accotink Creek's "Watershed 911" page - . We will be following this incident, and are particularly interested in learning:
Location of industrial park stormwater pond and vernal pool
Fairfax County website lists the stormwater pond as DP0353. "DP" means dry pond, but it has held permanent water for years.
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