If you have a catch basin (drain) on your property; you might want to go take a look at it. Simply walk over to the catch basin and look down between the grates. If you see sediment, sludge, or other things lurking near the grates then it may be impacted and in need of clearing. (Contact DGC Environmental to clear your impacted catch basin) Take a look at our client’s catch basin which was impacted by over 80% sediment and grease.
Fence line after hardwood removal from a ditch, in ST. Petersburg, Fla. The ditch is located behind a retention pond which had a lot of vegetative growth. This vegetative growth impacts the natural flow of stormwater, preventing the water to properly permeate through the soil. The trees also caused damage to the privacy fence around the retention pond. DGC Environmental Services went into the ditch and removed all the hardwood.
The pond was used as a sediment pond during construction of the property and once construction was completed, the pond was never scraped out and built to the plan specs.
We ended up removing 380 yards of sediment and then brought in new fill to get the pond back to the correct elevation. There should have been an infiltration trench installed in the pond but it was never installed. This pond is considered a water quality pond due to its size and then drains offsite into another detention pond. We had engineers redesign the infiltration trench since the required depth could not be met and have positive flow.
Once designs were approved for the design change, we dug out the trench, installed our geotextile and set the drain line.
We then backfilled over the pipe with #57 stone and formed a trench down the middle.
Next, we installed the riprap at the inflow structure. Then, we seeded the disturbed areas and covered with coconut fiber. Finally, we installed a silt fence around the rock bed until complete stabilization is achieved.
Sediment removal is complete. The site has been surveyed. Now, we discovered that the infiltration trench never installed. And, the pond was graded to the wrong elevation. We are bringing in new fill and using a laser to correctly grade the #pond. We have added additional #BMPs to ensure we do not have any #sediment release and our #turbidity is within compliance. Once the engineers have come up with an approved revision to the trench and low flow orifice, we will be on our way to completing this project. Stormwater systems are at the core of what we do here at DGC. Reach out to us with any questions or concerns you might have with your #stormwater #systems
Our environmental cleanup team was called to a property where years of illegal dumping created artificial dams and caused a creek to back up. We cut a few temporary channels to help move the water downstream but this is just the start of a larger cleanup project. What you are seeing is years of debris catching certain choke points which allow sediment and other debris to build up and block the flow of water. This system experiences flooding upstream on several sites.
If your property has fallen victim to illegal dumping or has been issued a violation; call DGC Environmental Services. We’ll come out and give you a free estimate for cleanup. 772-467-9224
We removed approximately 5 tons of sediment from two concrete flumes and disposed of the material at an off-site location. Once the stormwater structures were cleared, we placed bed sod on all the impacted areas.
When stormwater structures become impacted they stop functioning which leads to flooding even with modest amounts of rain. Contact Us for a Free Stormwater Evaluation today!
Over a period of time (long or short Period) sedimentation gathers along the bottom of the storm water pipes. To get an accurate video inspection we remove all sediment along the entire length of pipe.
There are many types of stormwater assets and even more methods for maintaining and repairing them. A Detention Pond is our main focus in this blog post and we will discuss how to remediate a detention pond that is not functioning properly. During and after a storm event, a detention pond collects stormwater that is conveyed to it from somewhere else (usually an impermeable surface close-by). Generally, the water that collects is supposed to drain - or percolate - back into the aquifer within a 72 hour time period. An easy way to remember the difference between a detention pond and a retention pond is after school detention ended and you were let go, whereas retention is a more long term scenario, holding water permanently.
There are a number of reasons why the stormwater in a detention pond might not percolate properly, including improper design and construction, incorrect fill media, and sedimentation - a build up of sediment transported by stormwater. Rectifying all of these issues is very important for the simple fact of safety and flood control. In addition, most regulatory agencies have compliance standards and consistently look for these non-compliant systems to issue Notice of Violations - NOVs. Ensuring your detention pond functions properly will save you money on maintenance and maintaining compliance.
Our case study is an excellent representation of a non-percolating detention pond that totals approximately 4,000 square feet and includes a concrete retention wall. The pond did not drain within the allotted 72hr period, at times became an eyesore due to algal blooms and unwanted vegetation was difficult to maintain for the contractor as they could not mow sod under water. On top of all that, this site was out of compliance and an NOV could have been right around the corner, literally - there is a regional field office for the local water management district less than two miles away from this location.
The processes involved in a project of this scope extend way beyond what one might think and various specialists are involved throughout the entire project. Geotechnical experts are occasionally consulted to provide geological surveys and soil analysis. Engineers and their assessments are consistently relied upon ranging from as-built drawings to any modifications that may need to occur. In the event of a modification to originally designed systems, additional permitting is ALWAYS required and opens the door for regulatory agencies and their involvement. Proper equipment and experienced operators are vital to the success of a project of this nature. Fences and gates are also a common piece of the puzzle that need to be handled accordingly. Unforeseen obstacles such as electric conduit or irrigation systems are always a concern; while ensuring proper trees and sod/seed are specified. Seed is usually preferred to sod due to the sedimentation that naturally collects in the sod at the sod farms.
Once the geotechnical items are handled, excavation can begin. The equipment operators will have been instructed on exactly how much earthwork needs to be done to satisfy the geo-parameters. A specific, predetermined depth is achieved and the foundation is scarified. Again, pre-determined choice of fill is brought in and distributed evenly across the area that has been excavated, careful not to impact the newly laid fill material. Trees are planted, grass seed is distributed and we wait for a rain event to see our handiwork in action!!
In conclusion, it is important to know what kind of stormwater assets you have and how best to maintain them. Detention ponds are meant to percolate back into the earth over a short period of time, and when that process is stagnated the pond needs to be repaired. There are many variables that can comprise the process and a proper plan of action is fundamental in a successful project. In the event that it needs remediating, having knowledgeable, experienced contractors is a very important aspect of the process. DGC Environmental is that knowledgeable, experienced contractor.
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DGC Environmental is the solution to your stormwater problem.
Erosion is the displacement of soil by water, wind or other natural agents. The severity of the erosion is dependent on the environment, water velocity, soil type, and vegetative or other coverage.
Most municipalities require that any erosion that occurs on a property to be repaired as quickly as possible and failure to do so could result in a Notice of Violation (NOV) which can incur fines. Erosion repairs can be expensive, so the best way to manage erosion is to prevent it.
When looking for a solution to an erosion problem, rip rap can be a cost effective option. When properly installed it can slow water velocity and offer coverage to protect venerable areas from erosion. The proper installation makes all the difference in the effectiveness of the protection the rip rap will provide. Rip rap is commonly large rock that is installed over prepared ground and secured geotextile fabric. With this method, the ground beneath the rock is stabilized and can offer years of protection from elements of erosion. Typically, rip rap is used around structures, on slopes and in high velocity areas. In addition to offering a solution for erosion issues, rip rap is esthetically pleasing.
Maintenance costs are reduced when rip rap is used around structures because the areas will be sprayed quarterly instead of trimmed monthly or bimonthly. It also reduces the cost of sediment removal because the soil is not displaced, so sediment accumulation is reduced. In one of our projects, a client was having drainage issues and it was found to be accumulated sediment in a mitered end structure. We removed the accumulated sediment and added geotextile fabric and rip rap at the end of the structure. After the repair was complete, the drainage issues were resolved.
Even though some sediment accumulation will occur within any stormwater system, the amount can be minimized with preventative measures.
Rip rap was one of the first forms of erosion control, used on the dams in the Panama Canal in the early 1900’s, so it is a tried and true method.
Contact us today for a site evaluation and erosion prevention plan.
Contact Us Today!
For a Site Evaluation and Prevention Plan