Asphalt and Stormwater Runoff

Asphalt and Stormwater Runoff

On rainy days, asphalt keeps floods and danger at bay. Here’s how.

Stormwater runoff is more potent than you might think; enough rainwater can cause rapid flooding, potentially destroying building foundations and endangering lives. Pavement engineering plays a large role in how stormwater flows to the nearest body of water, reservoir, or water treatment plant. In Maryland, there are at least two ways that asphalt and stormwater runoff can relate, and the difference is the asphalt type.

Traditional Asphalt and Stormwater Runoff

Conventional asphalt is impermeable, meaning no water or debris can seep through it. The only case water can enter the surface is when the asphalt cracks from age or wear, and this water penetration is not good for your asphalt pavement. 

Water runs off of impermeable pavement to the nearest storm drain or wherever gravity will take it. Engineers grade the pavement’s surface so that the water will flow at a precise speed toward the correct location, often a storm drain. The storm drain pipes also have a slope that carries water at a steady rate.

The potential concern with traditional asphalt and stormwater runoff is that the water could carry debris and chemicals with it into local bodies of water. Another concern is an overflow in the storm drain pipes. 

Permeable Asphalt and Stormwater Runoff

The push for permeable asphalt, concrete, and pavers has surged in recent years as another solution. Permeable asphalt has a porous asphalt top layer with gravel and a drainage basin underneath it. The water soaks into this basin and has more time to slowly drain into the soil or a stormwater runoff pipe. There are many videos online showing just how quickly water seeps right through permeable asphalt, as if by magic.

Concerns about permeable pavement are that the asphalt pores could become clogged or that it could break down faster than conventional asphalt. Even so, permeable pavement is a solution professionals agree on, whether in the form of asphalt, concrete, or pavers. 

Reliable Contracting knows the asphalt industry well, including aspects such as grading and stormwater management. Our company also has a utility division specializing in the design and installation of stormwater and sewer line systems. If you are curious about which type of asphalt to use for your commercial, industrial, or municipal project, contact us!


Reliable is dedicated to delivering quality products, displaying professionalism within the firm, seeking new opportunities for expansion and profitability, and providing an environment for individual success. If you have a commercial or residential construction project that you need taken care of, please contact Anne Arundel County’s largest site-work contractor today by calling 410-987-0313 or visiting our website. You can also follow Reliable Contracting on Facebook, LinkedIn, Pinterest, and Twitter!

Reliable Contracting Company serves the following and surrounding counties: Annapolis, Queen Anne’s, Anne Arundel, Baltimore, Baltimore City, Calvert, Caroline, Charles, Howard, Prince George, St. Mary’s, Talbot, and Washington D.C.

This entry was posted on Thursday, October 13th, 2022 at 10:33 am. Both comments and pings are currently closed.