When stormwater runoff flows down driveways it causes drainage issues and potential flooding in residential buildings, particularly the garage area. Here are some key points to consider:

Stormwater Entry via Garage

One common location for stormwater to enter a residential building is through the garage. If the driveway is not properly designed to handle stormwater runoff, it can flow into the garage, leading to water damage and potential structural issues.

Driveway Slope and Drainage Problems

Drainage problems are more likely to occur when the driveway has a steep slope that descends towards the garage. Steep driveways can facilitate faster and uncontrollable stormwater flow, making it challenging to manage and control runoff.

 

Compliance with Design Standards (AS2890.1)

To avoid drainage issues, driveways should comply with the design standards outlined in AS2890.1. This standard sets guidelines for driveway slope, height, and width, ensuring proper water management and safe vehicle access.

 

Gradient Changes

It’s crucial to design gradient changes on driveways carefully. Sudden changes in slope can lead to vehicles scraping their undersides, causing damage. Proper planning and gradual transitions are necessary to avoid this issue.  When dealing with steep driveways, special attention should be given to the points where the gradient changes. Proper design and implementation of these changes can significantly impact the flow of stormwater.

Controlling Stormwater Runoff

Managing stormwater runoff is essential to prevent flooding and water damage. Designing effective drainage systems, such as slot-drain drainage systems, can help divert stormwater away from the garage and residential building.  Assess and consider various potential sources of stormwater run-off that might affect the driveway and garage area. These sources can include excess stormwater flowing along the street, stormwater spilling into the driveway due to its low position, and direct rainfall landing on the driveway.

 

Slot-Drain Drainage System

Slot drains are commonly used to capture and redirect stormwater run-off from driveways. While they can effectively manage run-off from minor storms, they may become overwhelmed during major storms or get partially blocked by leaf litter. Maintenance and proper consideration of their hydraulic capacity are necessary.  Consider additional strategies to divert stormwater away from the garage, especially during major storms.

Non-Slip Treatment for Slot Drain Grates 

If slot drains are used on steep driveways, it’s essential to treat the metal grates with a non-slip material to provide adequate grip for car tires during wet weather.

Potential Sources of Stormwater Runoff

Stormwater runoff can come from various sources, including rainfall, melted snow, or excessive irrigation. Properly planned and implemented drainage systems can redirect this runoff away from vulnerable areas like the garage.

Managing Stormwater Run-Off from Steep Driveways

Steep driveways can present challenges in managing stormwater run-off. Consider recessing the garage door back from the house’s front alignment to allow more room for stormwater to pool and enter the slot drain. Elevating the garage floor slightly can also help prevent stormwater from entering the garage.Addressing stormwater runoff on driveways requires compliance with design standards, careful consideration of gradients, and the implementation of effective drainage systems. This will help prevent driveways from becoming waterways and ensure the protection of residential buildings from water-related issues and is crucial for mitigating potential flooding and water damage in residential buildings, particularly in garage ares.

 

Top Tips

 

Permeable Surfaces

Consider using permeable materials for driveways and parking areas. Permeable surfaces allow water to infiltrate into the ground, reducing the amount of runoff flowing down driveways.

Rain Gardens 

Implement rain gardens or bioswales alongside driveways to capture and retain stormwater. These planted areas can help slow down and filter runoff, allowing the water to be absorbed naturally. Gutter and Downspout Management properly functioning gutters and downspouts are essential for redirecting roof runoff away from driveways and buildings. Regular maintenance and cleaning of gutters are necessary to prevent blockages.

Rainwater Harvesting

Consider incorporating rainwater harvesting systems, such as rain barrels, to capture and store runoff for later use, reducing the volume of water flowing down the driveway.

 

Gutter and Downspout Management

Properly functioning gutters and downspouts are essential for redirecting roof runoff away from driveways and buildings. Regular maintenance and cleaning of gutters are necessary to prevent blockages.

Porous Pavers 

Instead of traditional concrete or asphalt, consider using porous pavers for the driveway. Porous pavers allow water to pass through them, reducing runoff and promoting natural drainage.

Underground Storage Systems

Implement underground storage systems to collect excess stormwater temporarily. These systems can slowly release the water into the ground or drainage system, preventing sudden and overwhelming runoff.

Detention and Retention Basins

Constructing detention or retention basins nearby can help manage stormwater runoff on a larger scale. These basins temporarily store and slowly release stormwater, reducing the risk of flooding downstream.

Local Regulations and Best Practices

Always check local regulations and best practices for stormwater management in your area. Some municipalities may have specific guidelines or requirements for addressing stormwater runoff.

Educate Residents

Educate residents about the importance of proper stormwater management and encourage them to adopt practices that minimise runoff, such as using rain barrels and avoiding overwatering lawns during heavy rainfall.By implementing these key points and adopting appropriate stormwater management practices, you can significantly reduce drainage issues and potential flooding caused by stormwater runoff on driveways in residential areas.

 

By implementing these key points and adopting appropriate stormwater management practices, you can significantly reduce drainage issues and potential flooding caused by stormwater runoff on driveways in residential areas.  Stormwater Sydney can assist in advising you in the best way of protecting your home from storm water runoff – contact us for a quote today.

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