MagnumStone Retaining Walls for Water Applications

Across the globe, rising sea levels and escalations of drastic weather events have become more frequent in recent years, resulting in devastating impacts. Increasingly severe flooding and erosion along coastal regions, have accompanied intensifying rainstorms and drainage challenges inland. As concerning as these trends are, precast concrete retaining walls have become an invaluable solution.

These long-lasting, durable products are equipping development and infrastructure projects with the capabilities to handle these issues better. From stormwater management systems to oceanfront seawalls, large concrete retaining walls like MagnumStone provide dependable, everlasting solutions. So let’s take a deeper dive into how concrete retaining walls offer flood and erosion protection for water application designs.

Key Considerations for Water Applications

  • Durability of Wet-Cast Concrete
  • Drainage Capabilities of Hollow Core Blocks
  • Water Flow Control Management

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Durability of Wet-Cast Concrete

Large wet-cast concrete blocks are an integral part of today’s infrastructure thanks to their versatility, and resiliency. The controlled process of wet-cast concrete production is instrumental to its performance. Having the ability to pre-cast the blocks in a controlled environment allows for premium production and extraordinary quality control.

Often times, production facilities will do regular testing of the concrete used inside the forms that are being poured to ensure the mix design meets the minimum specifications for the project. For instance, if an oceanfront retaining wall project requires a high performance concrete 11,000 PSI (75 Mpa), this can only be achieved by batching a specific concrete for the project.

Wet-cast concrete also has a low-absorption, weather-resistant composition that preserves its long-lasting strength for decades. Withstanding nature’s harshest elements is a signature quality of precast concrete and a primary reason why retaining walls like MagnumStone are trusted by engineers, contractors and landowners.

Drainage Capabilities of Hollow Core Blocks

It’s no secret that the main culprit behind most retaining wall failures is water. The real secret is that effective drainage is the unsung hero of any retaining wall project. Thankfully, big block systems are becoming more sophisticated to prevent issues caused by water damage.

That’s why MagnumStone’s hollow core retaining wall blocks are proudly designed for superior drainage. Each block is filled with clear crush gravel for excellent vertical drainage that complements perforated drainpipes in the horizontal core behind the block facing. This lets water flow freely and minimizes clogs by debris and soil fine buildups.

Water Flow Control Management

Now that we’ve covered the importance of efficient drainage, controlling where the water goes afterward is essential too. Grading the land below retaining walls and safely directing water away from infrastructure and buildings is always recommended – unless the retaining walls are part of an engineered water containment system.

Gabion basket retaining walls, for instance, provide excellent drainage but often can’t properly redirect water with drainpipes and strategically placed outlets. With today’s modern alternatives to gabion baskets, retaining wall systems like MagnumStone offer safe, reliable ways to control runoff.

Main Types of Retaining Wall Water Applications

  1. Coastal Retaining Walls
  2. Lakefront & Riverfront Walls
  3. Stormwater Management
  4. Conveyance Channels & Streambanks

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Coastal Retaining Walls

If you live along the coastline, you know exactly how punishing large bodies of water can be on retaining walls. Built to shield land from crashing waves, hurricanes and tropical storms, coastal retaining walls have a tough job description. Battered by the elements and constant tidal movement, they also deal with sea water’s harsh salinity.

Oceanfront precast retaining wall projects are vital to reducing erosive deterioration and protecting our coastlines. They last decades and also help preserve historic land for future generations. Additional preventative measures can help reduce wear and tear on these retaining walls, like placing large boulders – known as rip rap – in front of the wall as an extra safeguard. Rip rap extends from the toe of the retaining wall to above the high water mark. It increases the wall’s lifespan by absorbing the impacts of waves and proactively limiting potential scour issues.

In recent years, precast big block retaining walls have been entrusted to replace many shoreline barriers and seawalls. The heavy-duty strength of precast big block systems like MagnumStone offer a resilient solution to protect port cities, coastal communities and oceanfront properties. Along the Atlantic Ocean, restorative projects like Poplar Island, in Maryland, USA, prove the effectiveness and eco-friendly benefits of MagnumStone retaining walls in marine conditions.

Lakefront & Riverfront Retaining Walls

Retaining walls have been installed along lakes and rivers for hundreds of years for safety and recreational purposes. While some are built as boat docks and personal watercraft (PWC) launches, they also minimize erosion and prevent seasonal flooding.

The major challenges of lakefront and riverfront retaining walls often include freeze-thaw cycles and rapid drawdown effects, which both take their toll along shorelines. To counteract freeze-thaw cycles and ice pressures caused by expanding (frozen) water, rip rap is a true game-changer. By protecting and stabilizing the soil surface, rip rap prevents damage like scour, erosion and frost heaves from developing around the retaining wall.

Rapid drawdown effect is commonly seen with dams and artificial lakes, which are drained and replenished on a seasonal basis. Quick reductions of external water can cause unstable conditions along embankments and slopes which create risks for shoreline retaining walls. MagnumStone’s hollow core blocks, backfilled with crush gravel and weeping tile can effectively promote safe drainage from behind the wall. A free-flowing drainage process eliminates hydrostatic pressures while MagnumStone’s gravel-filled blocks remain firmly rooted in place.

Stormwater Management Systems

As record growth of parking lots, sidewalks and roadways continues, safely dealing with stormwater is now essential to residential, commercial and infrastructure developments. Natural open fields that used to absorb rainwater are now becoming paved impermeable surfaces in need of strategic drainage planning. Since paved surfaces act as an umbrella, runoff requires proper removal – and controlled direction to safe areas – to avoid major flooding and hazardous erosion.

Stormwater management has therefore become a critical design consideration for any development project. Precast retaining walls have become a driving force to help build and innovate stormwater management systems. The solutions they offer are comprised of many techniques including dry ponds integrated within recreational parks to retention basins that contain stormwater year-round.

MagnumStone’s hollow core blocks are excellent for any stormwater application, from eco-friendly bioretention ponds and open-air closed water storage systems. MagnumStone blocks also make it easy to prevent pooling of water and erosion by positioning drainage outlets along these water applications which redirect runoff away from vulnerable land and structures.

Conveyance Channels & Stream Banks

Concrete reinforced stream banks and canals are highly effective ways to manage stormwater runoff too – especially in large volumes. The performance of weather-resistant precast retaining walls helps them withstand surging flows and water levels brought on by persistent rainfall or centennial flooding events.

These conveyance channels are lined with precast big block retaining walls which have protected countless homeowners, businesses and communities from devastation. Their main function is to quickly capture, control and guide sporadic water volumes downstream to larger receiving waters like rivers and streams. The advantages of large hollow core blocks are their drainage capacity and secure, powerful strength that prevent erosion and scouring.

While runoff is collected from different sources like storm drains, street gutters and piping systems, controlling the water flow is a key component to handling fierce, erratic water levels. These water applications typically have vegetation, step pools or weirs to slow and control excessive flow rates.

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The innovative advantages of precast big block retaining walls for water applications are bound to establish a strong foundation for generations of future worldwide infrastructure development. By keeping these key considerations in mind, long-term prevention of erosion, flooding and scouring along exposed land can be planned for and protected by precast retaining wall solutions.

For more details, check out the advantages of MagnumStone’s stormwater management applications here or sign up for our monthly Retaining Knowledge communications.  


Photos: York Building Products, Barkman Concrete, Midwest Block & Brick and Oberfields LLC


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