User:Willdeaton31/sandbox

= Overview = With an increases in urbanization and expansion of the use of pavement, rainwater runoff has nowhere to go. In urban areas where there are very few green areas, only around a tenth of the rainwater that falls is absorbed into the ground (Weller). That’s why Tarmac, a United Kingdom company, created a new product called Topmix Permeable. This product now only cuts down on the use of gravel and sand, but also acts as a sponge soaking up and releasing water safely into the ground below a roadway. This product has revolutionized the construction, in addition to the safety of roadways (Matchar).

Description / Applications
Topmix permeable has huge technical applications and can play a fundamental role in the lives of everyday people. Topmix Permeable is a new, fast draining concrete pavement solution, which rapidly directs excess water away from streets, parking surfaces, driveways and walkways. In one square meter, this pavement solution can absorb 150 to 1000 liters per minute. According to a pamphlet created by the company Tarmac, Topmix Permeable is not like “conventional concrete, it has a high void content of between 20-35%. This allows surface water to drain through into the sub-strata and dissipate naturally, reducing the risk of surface water flooding and watercourse contamination” (Lafarge Tarmac).

Designs / Options
In addition to having a variety of finished colors, Topmix Permeable has three typical systems that can be used during the construction of the product.

System A
This system is known as the "Full Infiltration" system. This method allows any rainfall that lands onto the pavement to go through the products top layer, pass through any of the lower sub-base materials, and straight into the ground below. Since this system does not discharge any water, this is best used where there are overworked and outdated drainage systems in place (Lafarge Tarmac).

System B
This system is a "Partial Infiltration" system. This system is constructed exactly like the System A except for a skeleton of pipes that at intertwined in the “sub-base” layer that is located below the surface and above the soil. This allows only a portion of the rainwater to penetrate the ground and the rest flowing through the pipes and into nearby drainage systems. This method is great for area where the soil in not able to absorb the amount of water that it is exposed to (Lafarge Tarmac).

System C
This system is now as the “Full Attenuation” system. This system is a further step from System B. In addition to the skeleton of pipes, this method also includes an impermeable membrane layer the is placed right above the soil. This layer does not allow any water to penetrate the ground but still allows it to come through the surface of the pavement and into the pipes. This system is best for areas that recycle water in large amounts (Lafarge Tarmac).

Effective Management of Runoff
Having the ability to control where and the amount of runoff from urbanized and developed areas could significantly reduce the risk of surface flooding.

Reduced pressure on existing systems
With the absorbent Topmix Permeable pavement, a surge of water can be drastically cut down, leaving the existing drainage systems open for the normal flow of runoff.

Improvements in water quality
With such a high void content, Topmix Permeable helps to improve the water quality of the runoff draining through the pavement. In addition, it also allows the water to filter through the ground, adding to the local supplies of groundwater.

Increased property values
Property developments with absorbent pavement products sell for a higher price due to the large amount of advantages.

Reduced Costs
Without the need for pipes, catchment basins, or any other aspect of modern day water management systems, Topmix Permeable assures not only a sound and environmentally safe way of dispersing storm water, but also a cost effective one.

(Lafarge Tarmac)