Four Signs Your Parking Lot Storm Sewers May Need Repair or Replacement

If your parking lot’s storm sewers require repair or replacement, there are some common issues you’ll likely notice first, including:

  • Pooling water around drainage areas and gathering debris
  • Rapidly deteriorating pavement near drainage structures
  • Overgrown vegetation and greater pest presence
  • The property’s structures are developing foundation issues

Your storm sewers are responsible for capturing runoff and channeling it away from the property. They aren’t sanitary sewer lines – a common area of confusion – which carry wastewater from buildings to water treatment facilities.

Storm drains are exposed to high volumes of water straight from nature – especially in the Houston area. That water carries dirt, rocks, broken glass, leaves, sticks and other debris. All of that wear can lead to drainage problems, which can lead to worsening pavement damage. To avoid expensive future repairs, pay attention to the following signs and act when they emerge.

1) Water is Pooling on the Parking Lot and Around Drainage Structures

If water is pooling on your parking lot, that’s typically the first sign that something is wrong with your parking lot storm sewers. It could also be a sign that the parking lot’s base is failing and subsiding, but if water is backing up onto the pavement, your drainage structures will at least need an inspection.

In many cases, the problem is as simple as debris clogging up the storm drains or catch basins. Insufficient drainage or improperly installed drainage structures may also cause clogs once they are overwhelmed by the volume of water draining from the property.

2) The Parking Lot's Pavement is Wearing Away Around the Storm Sewers

If waterproofing admixtures are added to concrete, it makes for a reliable drainage surface. Waterproofed concrete is durable and provides excellent hydraulic efficiency, but it isn’t invulnerable to water damage. Over time, Houston’s heavy rainstorms will wear away at your parking lot’s pavement, including its storm sewers and drains. Regular maintenance can mitigate this wear, but if it has been a while since your last round of pavement maintenance, your storm sewers may be showing signs of damage – such as aggregate eroding and washing away into drains.

Other signs of pavement damage include cracks and spalls, and these can also indicate that your storm sewers need repair or replacement, especially if water is pooling around the damaged areas.

3) Vegetation is Present Around the Storm Drains

Thick vegetation and tree roots are subtle, often unrecognized sources of damage to parking lot sewers. Grass, weeds, shrubs, and trees will eventually extend their roots into your drainage structures if they are allowed to spread unchecked. It is common for pavement crews to uncover thick root structures choking parking lot drains.

If there is overgrowth emerging around your storm sewers, there is a chance that growth extends into the sewer line itself. It may also bring additional pests with it, which may be noticeable if they spread out from the parking lot.

4) Foundation Problems are Starting to Emerge on the Property

Foundation issues are often the result of shifting soils, which itself may be exacerbated by drainage problems. Unstable soils place concrete foundations under extreme stresses, leading to structural issues if not promptly addressed.

In Houston, there are large areas of clay-rich soils that swell like a sponge during rainstorms and shrink once the weather dries out. This expand/contract cycle is made worse by poor drainage, as those soils have more time to soak up water that cannot flow from the property right away.

If your facilities seem to be built on a shaky foundation, the problem may be traced back to a damaged storm sewer.

How Do Pavement Contractors Manage Storm Sewer Repairs?

If you are concerned about the state of your storm sewers, a reputable pavement contractor can handle any repairs or replacement. This may involve the following:

  • A detailed inspection – The pavement team will not know what to repair or replace until they can perform a full inspection of the parking lot’s storm sewers. They may only need a quick visual to confirm the problem, or they may thread a camera into the sewer line to get a closer look. The goal is to identify what issues need to be corrected to ensure a long-term repair.

  • Sewer line cleaning – Regardless of what repairs are needed, the storm sewers will first need to be cleaned out. This ensures the pavement team has a clear site to work with. Hydro jetting (using high-pressure water jets) is one way and is probably the most cost-effective way to clear out storm sewer lines.

  • Excavation – If the pavement team needs to access below-ground drainage structures, it will do so using excavators to dig out the site.
  • Repair or replacement – Once the damaged storm sewer is accessible, the pavement team may perform the necessary repairs or replacement. This could be as simple as filling a few cracks or patching some spalls, or it could be as complex as removing fractured concrete pipes and installing new pipes.

Once the pavement crew is done with the storm sewer repairs, they will backfill any excavated areas and replace any pavement that was removed during the process.

Consult with Paving Professionals if Your Parking Lot's Storm Sewers are Showing Signs of Distress

Drainage problems tend to develop over time and are typically subtle at first. That means by the time your storm sewers are showing clear signs of distress, there could be significant issues that need addressing. If your parking lot’s drainage is not as efficient as it should be, consider scheduling an inspection with an experienced pavement contractor. During an inspection, your pavement team will identify the issue behind your storm sewer problems and determine whether repairs or replacement are in order.