Seattle Drainage Services

Washington Commercial Drainage Company

For a moment, think of your asphalt as though it were a hospital emergency room. Hospitals use triage, “a process for sorting injured people into groups based on their need for or likely benefit from immediate medical treatment. Triage is used in hospital emergency rooms, on battlefields, and at disaster sites when limited medical resources must be allocated.”

It might seem a silly stretch to compare asphalt maintenance to important life-saving decisions, but some of the same principles can be useful. A common approach to maintenance (of all kinds) is to employ a so-called “worst-first” strategy. This dictates that the items in the worst disrepair should be addressed first. This isn’t always the most prudent method, however. With limited budgets, a better approach is to sort problem areas into groups based on their “likely benefit from immediate treatment.” For example, it may make sense to forego expensive repairs on one half of a property in the short term to provide low-budget preventative solutions on another corner of the property that is still in good shape.

According to the Asphalt Institute, the top three contributors to asphalt damage are “water, water, and water.” While we cannot control how much water falls out of the sky, we can employ strategies to manage water flow and drainage efficiently. Thankfully, many of the solutions related to water drainage are also low-cost propositions including installation of berms, repairs of sinking or damaged catch basins, installation of trench drains, or subsidiary catch basins and dry wells.

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The links below will take you to data sheet and manufacturer’s specifications for the various products we use.

Drainage FAQ’s

What is a berm?

A berm is like a miniature speed bump and is used to divert or direct water toward catch basins or areas where the water can flow off the asphalt onto a permeable surface.

Can you raise or lower a catch basin?

Both can be done. There are “risers” or “spacers” between the “basin” and the surface grate. These can be added or removed to achieve the desired height.

What is the difference between a storm drain and a dry well?

A storm drain is a large-volume storm water management system that captures water at the surface at grated “catch basins” and collects and consolidates water from a large area. Most drains have a single large exit at their point of discharge into a canal, river, lake, reservoir, sea or ocean. A dry well collects water in a similar fashion at the surface, but is designed to discharge slowly into the soil and is meant only for small volumes of water.

How can I get rid of puddles on my parking lot?

Standing water on the parking lot surface is not a good thing. It will promote early deterioration and failure. We can employ different strategies depending on the depth and total number of puddles. Rather than try to “re-grade” the surface, it is usually best to try to harness what gravity is already doing and capture water at the existing low spots and deliver it to an existing storm drainage system. This can be done by placement of new catch basins or trench drains at the surface. Berms are also productive in “steering” water away from problem areas to begin with.

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