What is exfiltration rate?
Exfiltration Rate The water that seeps from the vegetated swale is lost from the catchment, and cannot re-enter the system downstream. Contaminants in the water that is lost to exfiltration are removed from the vegetated swale, along with the exfiltrated water and are also lost from the catchment.
What is the difference between exfiltration and infiltration?
is that exfiltration is (military) the process of exiting an area (usually behind enemy lines or in enemy territory) while infiltration is the act or process of infiltrating, as of water into a porous substance, or of a fluid into the cells of an organ or part of the body.
What is exfiltration hydrology?
Exfiltration is a term used by Hydrology Studio indicating flow exits the pond. It can be used interchangeably with infiltration. Exfiltration flows are based on the contour area at each stage or elevation.
What is an exfiltration system?
Exfiltration Systems In general, exfiltration is an engineering term used to describe the movement of. stormwater out of a designed water management system. Systems that allow. Stormwater to exfiltrate include perforated pipes and underground chambers.
What is the purpose of exfiltration trench?
They function in concert with pervious surfaces by enhancing the infiltration and storage capacity of on-site soils and treating runoff before it recharges the groundwater. Exfiltration systems act as small, distributed, underground stormwater retention ponds.
How does exfiltration trench work?
Similar to the concept of the French drain, an exfiltration trench filters runoff through a catch basin slowing down the volume of discharge. From here it passes through a screened inlet before en- tering into a perforated pipe.
What is infiltration tank?
Infiltration tank for controlled drainage of rainwater into the groundwater.
What is vegetated swale?
A vegetated swale is an open channel that collects stormwater and allows it to infiltrate into the ground. The grass or plants covering the side slopes and bottom provide a filtration surface for the water and help slow the flow rate. Many swales have an underdrain pipe to manage larger storms.
How do you calculate ACH?
The formula to calculate ACH is 60 multiplied by the cfm of your air exchange device, divided by the volume of air in the room.
What is the normal rate of exfiltration?
Typical Exfiltration Rates Exfiltration velocity can vary widely depending on soil conditions and groundwater levels. Common values may fall anywhere from 0.1″ to 100″ per hour (2 to 2500 mm/hour). For designs that are critically dependent on the exfiltration rate, actual site testing is recommended.
What is a water exfiltration test?
The water exfiltration test shall include testing of the seal between the cast iron frame and the concrete cone, slab or grade rings. The manholes shall be backfilled and finished to design grade.
How do you find the exfiltration velocity?
For other scenarios, the exfiltration velocity can be determined by multiplying the conductivity by the hydraulic gradient. Note that Darcy’s Equation applies only to saturated media. For unsaturated conditions, other effects such as capillary action must be considered in determining the exfiltration velocity.
How can I calculate the available area for hydraulic exfiltration?
3) You can specify the saturated hydraulic conductivity, and have the exfiltration calculated by Darcy’s Law based on the distance to groundwater. The available area can be based on either surface area or wetted area, and may exclude areas that lie above or below specified elevations.