Exact Stormwater Management

Bioretention facilities, sometimes called Rain Gardens, are nature-inspired stormwater management solutions. They're like mini-ecosystems designed to capture and treat stormwater runoff.

A bioretention facility typically consists of a shallow depression filled with a mix of specialized soil, organic matter, and vegetation. This combination creates a bioengineered environment capable of mimicking natural processes.

When it rains, stormwater runoff flows into the bioretention facility. The depression acts as a capture zone, holding the water temporarily. Some designs include a network of pipes to convey runoff directly into the facility.

Bioretention systems use specially designed soil and vegetation that act as natural filter, removing pollutants and impurities from the stormwater. The soil allows water to slowly percolate through, providing physical and biological treatment along the way.

Plants play a crucial role in the bioretention process. Their roots help stabilize the soil, and they absorb nutrients as they grow, further improving water quality.

In case of heavy rainfall, bioretention facilities are designed with an overflow mechanism. This ensures that excess water is released slowly, preventing flooding and erosion downstream while still allowing for natural infiltration.

These nature-inspired solutions are a powerful tool in the fight against stormwater pollution, helping keep our waterways clean and free of contaminants.

Bioretention facilities are fantastic tools for managing stormwater, but they will require regular inspections and maintenance to stay effective. Identifying problems early will help ensure the system can remain healthy. When inspecting your facility, here’s what to look for.

Walk around the bioretention area and look for any obvious signs of issues – like standing water, erosion within or on the banks of the system, and dead or damaged plants.

Check for mulch wash-outs, as well as sand or sediment buildup, especially around inflow points. Look for other potential signs of clogging across the surface of the system.

Make sure the vegetation is healthy. Check for signs of stress, like wilting or discoloration. Dead plans should be replaced. Weeds and invasive plants should be removed. Vegetated cover of 75-90% throughout the facility is necessary to keep it functioning as intended.

If you’ve noticed water standing in the system for more than a day or two after it rains, consider performing a simple infiltration test. Pour water onto the bioretention surface and observe. If the water isn't soaking in as quickly as it used to, there might be an issue with the soil or the underdrain. Check the outlet structure to ensure there’s no accumulated debris blocking water flow.

Lastly, check the overflow mechanism. Make sure it's clear of debris and functioning properly. This ensures that excess water is released appropriately during heavy rainfall.

Regular checks help catch issues early, keeping your bioretention system happy and effective. If you find any issues or the system just isn’t working like it should, consider calling stormwater professionals to maintain it. Your bioretention facility is designed to help keep stormwater runoff and the natural waterways it flows into clean, but it’s going to need your help. With regular inspections and occasional maintenance, your bioretention system is going to do amazing work to keep the waters in your town clean and beautiful.

Bioretention facilities are nature-inspired marvels that require proper care to be able to function as they’re intended to.

If you haven’t done an inspection, our team of licensed professionals can get that done for you. If you’ve already had an inspection on your system and noticed erosion or scouring, standing water, dead plants, or any other issues, we can help resolve any issues that have been documented.

Sometimes, bioretention systems don’t seem to be working right or they’re running slow, and you need some help diagnosing the problem. Exact will perform a thorough forensic investigation to help determine the issues in your system, and will help create a plan to remedy the problem.

Exact is your go-to partner for your stormwater management needs. With our innovation & expertise in stormwater management, let's work together to make a lasting impact.

Before a bioretention system can be installed, the contributing drainage area, or the area where runoff rainwater will enter the system, must be stabilized with vegetation. Then, the excavation for the bioretention area is made according to design depth and dimensions.

Geotextile fabric is lined across the sides of the bioretention area, and then the first layer, the stone, is installed from the bottom, with the amount based on the design specifications. During this process, the underdrain pipe will be installed, as well. The media, consisting of soil, sand, and organic material that acts as the primary filtering medium, is what makes up most of the underground part of the system. The media is installed in 12-inch increments until the desired top of the system’s area is reached. This is done over the course of several days to keep the media from settling.

The above-ground area is then prepared for the proper vegetation to be installed by having planting holes made. The surface cover, usually mulch, river stone or turf, is used to top off the system’s main filtering area. Finally , the necessary vegetation, as intended by the design, is installed. They should be actively watered during periods of no rain for two months after installation.