In New Zealand, where rain can be heavy and unpredictable, effective drainage is vital for homeowners to protect their property and prevent water damage. But with various drainage solutions available, many property owners face the dilemma of choosing between surface and subsurface drainage systems. Each has its unique role and advantages, and selecting the right one depends on your landscape, soil type, and drainage needs. In this comprehensive guide, we’ll explore the key differences between surface and subsurface drainage, and provide insight into which solution may best suit your property.

Understanding Surface Drainage

Surface drainage is designed to remove excess water from the ground's surface, typically after heavy rains or storms. Surface drainage solutions are visible, as they involve trenches or channels that collect and redirect water away from the property. Some examples of surface drainage include:

• Swales: Grassy or gravel-filled depressions that channel water away from your property.
• Open ditches: Trenches dug to move water quickly off-site.
• Runoff channels: Channels that lead water away to a designated drainage area.

Benefits of Surface Drainage

1. Prevents Pooling on the Surface
   Surface drainage is ideal for quickly removing water that accumulates on top of the ground. This can prevent flooding, reduce the risk of mud build-up, and keep your lawn, driveway, and other areas dry.
2. Cost-Effective Solution
   Surface drainage systems generally require less installation work and are therefore less costly than subsurface options. For New Zealanders looking for a budget-friendly option to tackle mild drainage issues, surface drainage could be the answer.
3. Easy Maintenance
   With visible components, surface drainage systems are easy to access and maintain. Blockages can be spotted and cleared quickly, making upkeep relatively simple.
4. Reduces Soil Erosion
   In regions prone to erosion, surface drainage can help channel water in a way that minimizes soil loss, preserving the integrity of your property.

Drawbacks of Surface Drainage

• Less Effective in Deep Saturation: Surface drainage works well for excess water on the ground, but it’s not effective for deeper saturation levels.
• Aesthetics: Surface drainage components can sometimes detract from the landscape aesthetics, although strategic planning and decorative finishes can help.

Understanding Subsurface Drainage

Subsurface drainage, on the other hand, is designed to remove water that has already seeped below the ground’s surface. This system involves buried pipes or drains that capture water deep within the soil and direct it away from the area. Common subsurface drainage options include:

• French drains: Perforated pipes surrounded by gravel and buried underground to capture and redirect groundwater.
• Drain tiles: Typically used around foundations, drain tiles capture water that seeps close to the structure.
• Sump pumps: Installed to pump groundwater from basements or other low areas in the property.

Benefits of Subsurface Drainage

1. Prevents Waterlogging and Soil Saturation
   Subsurface drainage removes excess water deep within the soil, which can prevent waterlogging in gardens, lawns, and around foundations, ensuring healthier plant growth and structural integrity.
2. Protects Foundations
   Water that sits too close to a building’s foundation can cause major structural issues over time. Subsurface drainage systems help prevent such damage, especially important in New Zealand’s rainy regions.
3. Aesthetic Appeal
   Since subsurface systems are buried, they don’t impact the look of your landscape. They provide efficient drainage without detracting from the aesthetics of your property.
4. Improves Soil Health
   By regulating soil moisture levels, subsurface drainage promotes healthy soil conditions, which can improve root growth and reduce plant diseases.

Drawbacks of Subsurface Drainage

• Higher Installation Costs: Installing subsurface drainage is often more labor-intensive and therefore more expensive.
• Maintenance Challenges: Because these systems are buried, it can be challenging to locate and repair any blockages or damages.

Surface vs. Subsurface Drainage: Which One Do You Need?

When deciding between surface and subsurface drainage, consider the specific conditions and needs of your property.

Assess Your Property’s Landscape

If your property has a relatively flat landscape, surface drainage can effectively divert water. However, for properties with slopes or where water tends to pool in low areas, subsurface drainage may be a better solution to manage groundwater and prevent saturation.

Evaluate Soil Type

The type of soil on your property plays a key role in determining the best drainage system. Sandy soils, which drain naturally, may only require surface drainage for rainy periods. Conversely, clay-rich soils tend to retain water and could benefit from subsurface drainage to prevent waterlogging and soil compaction.

Consider Your Vegetation Needs

Surface drainage works well for areas with lawns and shallow-rooted plants, as it effectively manages surface water without disrupting the soil beneath. For deeper-rooted vegetation, subsurface drainage ensures that water doesn’t saturate the soil, promoting healthier growth conditions.

Budget and Aesthetic Preferences

Surface drainage systems are generally more budget-friendly, while subsurface systems offer a discreet, underground solution. If you’re concerned about the appearance of visible drains or channels, subsurface drainage may be the right choice.

Combining Surface and Subsurface Drainage Systems

For many New Zealand properties, the best drainage solution combines both surface and subsurface systems. This dual approach provides comprehensive water management that addresses both surface runoff and deep soil saturation. By implementing a hybrid drainage system, you can:

• Maximize water diversion: By tackling both surface and subsurface water, you reduce the risk of waterlogging and pooling.
• Enhance property resilience: Combining both systems helps protect your landscape, plants, and structures.
• Reduce maintenance costs: With water managed more effectively, you may experience fewer issues with blockages, soil erosion, and other maintenance needs.

Choosing the right drainage system is crucial to maintaining a functional, beautiful, and resilient property, especially in New Zealand’s rainy climate. Whether you’re considering surface drainage, subsurface drainage, or a combination of both, Real Drainlayers has the expertise to assess your property and install the ideal solution. Contact us today to learn how we can protect your landscape and property from water damage with a customized drainage solution tailored to your needs.

New Zealand is known for its unpredictable and often heavy rainfall, making proper drainage solutions essential for homeowners and businesses alike. With the wet weather conditions, flooding, erosion, and water damage can occur quickly without the right drainage systems in place. If you're looking to protect your property from the effects of heavy rain, understanding the best drainage solutions for New Zealand’s rainy seasons is crucial.

In this blog post, we’ll explore the key drainage solutions that can help safeguard your property, keep your yard dry, and prevent water damage, ensuring your home or business remains safe and functional throughout New Zealand’s rainy seasons.

Understanding the Importance of Drainage in New Zealand

Before diving into specific drainage solutions, it’s important to understand why drainage is so critical in New Zealand. Our climate can vary dramatically from one region to the next, but one thing remains constant: heavy rainfalls, particularly during the winter months.

The average rainfall in New Zealand can be significant, with some areas receiving upwards of 1,500 millimetres annually. These heavy rains, combined with often compacted or poorly draining soil, increase the likelihood of water pooling around the foundation of homes, causing erosion, basement flooding, and landscape damage.

Without proper drainage systems in place, the excess water can not only create unsightly puddles but can lead to significant long-term damage to your home and property.

Key Drainage Solutions for New Zealand’s Rainy Seasons

1. French Drains: A Time-Tested Solution for Water Control

French drains are one of the most popular and effective drainage solutions for homes that deal with excess surface water. A French drain is essentially a trench filled with gravel or rock that directs water away from critical areas, such as the foundation of a house or garden beds.

The concept of a French drain is simple but powerful: a perforated pipe sits at the bottom of the trench, allowing water to enter the system and be channeled away from your property. This is especially useful during heavy rainfall when water tends to accumulate in low areas of the yard.

In New Zealand, French drains are often used around building foundations to prevent water from pooling, which can weaken the structure or lead to flooding in basements and crawl spaces.

2. Sump Pumps: Protecting Basements and Low-Lying Areas

For homeowners with basements or homes situated in low-lying areas, sump pumps are an invaluable tool during New Zealand's wet seasons. A sump pump is installed in a sump pit, usually located in the basement, which collects water as it drains down from the foundation.

Once the water level in the pit rises above a certain threshold, the pump activates, pushing the water away from the property and into a drainage system, typically leading to a stormwater drain or a dry well.

Sump pumps are ideal for homes that experience basement flooding during heavy rainfall or have moisture problems that need to be managed. Regular maintenance of sump pumps, such as clearing debris and testing the motor, is essential to ensure they work effectively when needed most.

3. Gully Traps and Manholes for Effective Stormwater Management

Another key solution for handling stormwater is the use of gully traps and manholes. These systems help to direct water away from homes and streets, ensuring that excess rainwater does not flood surrounding properties.

Gully traps are commonly installed at low points in a property or near downpipes to catch rainwater before it spreads across the ground. From here, the water flows into stormwater drains or manholes, which are large access points that allow for easier maintenance and inspection.

For both commercial and residential properties, installing a well-maintained gully trap system can prevent water from building up in vulnerable areas like driveways or patios. These systems are particularly useful for urban areas in New Zealand where stormwater management is a priority.

4. Driveway Drainage: Preventing Water from Pooling on Pavements

Driveways are often the first line of defense against flooding, especially if your driveway slopes toward your home. During heavy rain, water can pool on your driveway, increasing the risk of erosion and water seepage into your property.

To prevent this, many homeowners install specialized driveway drainage solutions such as channel drains, trench drains, or surface drains. These systems direct water off the driveway and into stormwater drains or collection pits.

In New Zealand, where properties often have sloped driveways or are situated in flood-prone areas, it’s essential to invest in proper driveway drainage. Not only does it prevent flooding, but it also ensures the longevity of your driveway, preventing cracks and water damage caused by trapped moisture.

5. Stormwater Drains: Directing Rainwater Away from Your Property

Stormwater drainage systems are perhaps the most well-known method for handling large amounts of rainfall. Stormwater drains are typically found in urban areas, but they can also be installed on rural properties to direct water away from your land and prevent water from pooling on your lawn or garden.

Stormwater drains are an effective way to prevent flooding during heavy rain, especially in areas prone to intense downpours. They can be connected to other drainage solutions, such as French drains or gully traps, to maximize water flow and ensure that excess water is diverted safely away from your property.

For homes in flood-prone areas or regions with poorly draining soil, stormwater drains are a must-have to prevent water damage, soil erosion, and landscape degradation.

6. Landscape Grading: A Preventive Measure for Long-Term Drainage

When it comes to preventing water damage in the long term, landscape grading is one of the best ways to ensure that rainwater flows away from your home. Proper grading involves adjusting the slope of the land around your property so that water naturally flows away from the foundation and into drainage systems like French drains or stormwater pipes.

In New Zealand, where many homes sit on uneven terrain or hillsides, landscape grading can be a crucial aspect of drainage planning. A qualified drainage specialist can assess your property’s grading and determine whether adjustments are necessary to optimize water flow.

Maintenance and Regular Inspections

Even the best drainage systems will require maintenance to function optimally, especially during New Zealand’s rainy seasons. Regular inspections of your drainage systems are essential to identify issues like clogged pipes, broken sump pumps, or damaged gully traps.

You should also check the integrity of your landscaping around drainage systems to ensure that soil, debris, or plant roots are not obstructing water flow.

It’s recommended to have your drainage system checked by professionals at least once a year, or more frequently if you live in a particularly flood-prone area. Regular maintenance will extend the life of your drainage system and ensure it’s always ready to handle heavy rain.

Why Choose Real Drainlayers for Your Drainage Solutions?

At Real Drainlayers, we specialize in providing effective drainage solutions for New Zealand homeowners and businesses. Whether you need to install French drains, sump pumps, or stormwater systems, our expert team has the experience and equipment to handle all your drainage needs.

We offer tailored solutions designed specifically for New Zealand’s rainy seasons, ensuring that your property is protected from flooding, water damage, and soil erosion. Don’t wait for the next heavy rain to find out that your drainage system isn’t up to the task. Contact Real Drainlayers today and get a comprehensive drainage solution to keep your property safe and dry!

Contact Us Today

If you’re ready to protect your property with reliable and efficient drainage solutions, reach out to Real Drainlayers today. Our team is available for consultations, inspections, and installations throughout New Zealand. Let us help you safeguard your home or business from the next storm.

If you've ever been in a situation where you needed to dig, whether for construction, renovation, or any other ground-based project, you've probably been introduced to the concept of excavation. But have you ever heard of Hydrovac Excavation? If not, then sit back, grab a cuppa, and let's get to know this modern, efficient, and safe excavation method. This article is for anyone keen to learn about new technologies or who might need excavation services, especially for tasks like drain unblocking.

Hydrovac excavation is a non-destructive method that uses pressurized water and an industrial-strength vacuum to quickly and safely expose underground infrastructure. It's an approach that's increasingly being adopted across New Zealand and globally, for its efficiency, accuracy, and reduced risk to both workers and existing infrastructure. It's particularly beneficial to those in the construction, utility, and even drain unblocking industries. Understanding how it works and when it's needed can not only save you time and money, but also contribute to safer working conditions. So, let's dive a bit deeper into this fascinating technique.

How Does Hydrovac Excavation Work?

Hydrovac excavation, as you might guess from the name, combines water and vacuum technology to provide a safe and efficient method of excavation. It's a bit like giving the earth a bit of a wash and vac, but on a much larger scale and with a whole lot more precision.

The process starts with the hydrovac truck shooting a high-pressure stream of water into the area that needs to be excavated. This water, under pressure, cuts through the soil and breaks it up. The soil becomes a slurry, which is a mixture of water and soil that's much easier to remove than solid earth. The real magic happens with the vacuum system. Attached to the truck is a large hose that suctions up the slurry, removing it from the excavation site. The slurry is then stored in the truck's debris tank, keeping the worksite clean and tidy.

The beauty of hydrovac excavation lies in its precision. Traditional excavation methods run the risk of damaging existing infrastructure, like gas lines, water pipes, and telecommunications wires. However, the use of water makes hydrovac excavation much more delicate and controlled. The water can't damage these utilities like a metal digger or shovel might. This precision not only saves time and money on potential repairs but also promotes safer working conditions. Whether you're working on a large construction project or unblocking drains, hydrovac excavation offers a compelling alternative to traditional digging methods.

When Would I Need Hydrovac Excavation?

Hydrovac excavation is a versatile technique and can be used in a wide variety of scenarios. One of the most common applications is for locating and exposing existing utilities. As mentioned before, the precision of hydrovac excavation makes it ideal for safely unearthing buried pipes and cables without causing damage. This process is known as 'daylighting' or 'potholing' and can save a heap of trouble when compared to more traditional digging methods.

You'd also need hydrovac excavation when you're up against tough or frozen ground. The high-pressure water does a top-notch job of breaking up hard soil and even ice, making it possible to excavate areas that would be challenging with other methods. It's also used for digging in areas that are hard to reach with traditional excavation equipment, like tight spaces or areas that are obstructed by buildings or other structures.

Then, there's drain unblocking. Over time, drains can become clogged with debris, and traditional methods of unblocking can be time-consuming and potentially damaging to the pipes. Hydrovac excavation, with its high-pressure water, can cut through and remove the blockage without damaging the drain infrastructure. It's a quick and efficient way to keep the drains flowing smoothly.

In short, if you need precise, efficient, and safe excavation, hydrovac is the way to go. From construction and utility maintenance to drain unblocking, it's a method that's proving to be a game-changer in the excavation industry.

What Are The Disadvantages of Hydrovac Excavation?

Like any technique, hydrovac excavation isn't without its drawbacks. One of the main disadvantages is that it can require a significant amount of water, which may not be ideal in areas where water conservation is a concern. Plus, the water used in the excavation process must be disposed of properly to prevent pollution, adding an extra layer of environmental consideration.

Weather can also affect hydro excavation. While it's true that hydrovac is great for dealing with frozen ground, the system itself can be affected by extreme cold. The water can freeze in the hoses and tanks, making the equipment difficult to operate. In areas with harsh winters, this could limit the times of the year when hydrovac excavation can be used effectively.

Cost can be another disadvantage. While hydro excavation can save money in the long run by preventing utility strikes and offering faster excavation, the upfront costs can be higher than traditional digging methods. The specialised equipment and trained operators needed for hydrovac excavation can be more expensive than hiring a standard backhoe and operator.

Lastly, the disposal of the soil and water mixture can be challenging. Unlike dry soil excavated by traditional methods, the slurry created by hydrovac excavation can't be easily used for backfill. It often needs to be transported off-site for disposal, which can increase project costs and time.

Essentually, while hydrovac excavation offers many benefits, it's important to weigh these against the potential disadvantages for your specific project and location.

What Happens During Hydro Excavations?

During a hydro excavation process, a series of steps are methodically followed to ensure safety and efficiency. It all begins with the hydrovac truck arriving on site. This specialised vehicle is equipped with a storage tank for holding water, a heater to warm the water if necessary, a vacuum tank for storing the excavated material, and a high-pressure hose and vacuum hose system.

The first step in the process is identifying and marking the excavation area. This is crucial for safety reasons and to prevent any damage to underground utilities. Once the area is marked, the operator begins the excavation process.

The hydro excavation process itself involves the use of high-pressure water to break up the soil. The operator directs the water jet towards the ground, and as the water pressure dislodges the soil, it creates a slurry of water and soil.

Simultaneously, a powerful vacuum is used to suck up this slurry, transferring it into a holding tank on the hydrovac truck. This process continues until the desired depth of excavation is achieved.

Throughout the process, the operator has precise control over the excavation, reducing the risk of damage to utilities and structures. Because the soil is being stored in a tank, it also reduces the mess on the excavation site.

After the excavation, the slurry is typically taken to a disposal site. However, it's important to note that in some cases, the slurry may be treated and used for other purposes, such as landfill cover or road construction.

In summary, hydro excavation is a careful, controlled process that involves high-pressure water to break up the soil and a vacuum to remove the resulting slurry, ensuring a clean and safe excavation.

Applications of Hydro Excavation

Hydro excavation is a versatile technique that can be used in a wide range of applications in the construction and utility industries. One of its most common applications is in the safe exposure of underground utilities. By using water to break up the soil, the risk of damaging pipes, cables, or other utilities is significantly reduced compared to traditional digging methods.

There are several scenarios in which hydro excavation can come in handy. Here are a few of the applications of Hydro Excavation:

• Exposure of Underground Utilities: Hydro excavation is frequently utilised for safely revealing underground utilities. Its method of using water to break up soil considerably reduces the risk of damaging pipes, cables or other utilities, making it a preferred choice over conventional digging methods.
• Slot Trenching: In scenarios where narrow trenches are required for the installation of pipes, cables, or other utilities, hydro excavation proves to be incredibly beneficial. The precision of this technique allows trenches to be dug to exact specifications, resulting in minimal disruption to the surrounding area.
• Piling Hole Excavation: Hydro excavation is employed in the construction of buildings, bridges, and other structures where piles are part of the foundation. This method can be used to dig the holes for these piles, ensuring accurate placement and appropriate depth.
• Debris Removal: The hydro excavation technique is also used for debris removal. Its precision and control over the excavation area make it an ideal choice for removing debris without causing any damage to the surrounding structures or utilities.
• Cold Weather Excavation: Hydro excavation can also be used in cold weather conditions where traditional digging methods may struggle. By using heated water, the process can effectively cut through frozen ground.
• Pipeline and Sewer Rehabilitation: Hydro excavation is ideal for pipeline and sewer rehabilitation projects. It can quickly and safely expose the pipeline or sewer line for repairs, reducing the risk of further damage to the system.

Whether you're in need of drainage repairs or simply aren't sure whether or not hydrovac excavation would benefit your drainage or property, it's always best to consult with a NZ drainage specialist first. Real Drainlayers helps put you in touch with drainage contractors who can guide you through the hydrovac excavation process and even determine if it's required for your type of drainage job.

Welcome to the world of wastewater management - a crucial, though not commonly discussed, part of life. In New Zealand, our approach to handling wastewater varies depending on location and available infrastructure. In our urban centres, we often take for granted that our wastewater is whisked away through an intricate network of pipes to be treated and safely disposed of. But what happens when you live in a more remote or rural area where the public sewage system doesn't reach? Enter the cesspit: a traditional yet still relevant method of managing wastewater.

A cesspit, though not the most glamorous of topics, plays a vital role in ensuring the health and safety of households and the surrounding environment, particularly in areas of New Zealand where other waste management systems are impractical or unavailable. This blog post aims to shed some light on what a cesspit is, how it works, its purpose and the regulations surrounding its use in Aotearoa. By the end, we hope to provide you with a clearer understanding of this often-overlooked, but essential, aspect of New Zealand's wastewater infrastructure.

What is a Cesspit NZ?

A cesspit, also known as a cesspool, is a type of waste management system used primarily in rural and semi-rural areas where connection to the main sewerage system is either impractical or impossible. It's essentially a sealed underground storage tank that collects all the wastewater and sewage produced in a household. Everything that goes down your drains - from the sink, shower, washing machine, and toilet - ends up in the cesspit. In New Zealand, they are commonly used in remote locations, such as the Coromandel and Great Barrier Island.

The cesspit system is relatively straightforward, but the installation and maintenance can be complex. Cesspits are installed underground and need to be large enough to handle the waste output of the household. The size of the cesspit will depend on the number of people in the household and the rate of water usage. To ensure the cesspit functions effectively and safely, it must be installed correctly, which typically involves excavation, lining the pit with watertight material, and installing access points for maintenance and pumping. This is typically a job for a professional drainage or waste management company.

In New Zealand, the use of cesspits is tightly regulated. They must be watertight to prevent leakage and contamination of groundwater. Moreover, the cesspit needs to be placed at a safe distance from any buildings or water sources to minimise the risk of contamination. It also needs to be easily accessible for regular emptying and maintenance, as cesspits do not treat or dispose of the waste, they merely store it. This means regular pumping out is required to prevent overflow and potential environmental damage. In some parts of New Zealand, such as Auckland, property owners are required to have their cesspits pumped out at least once a year.

How Does a Cesspit Work?

A cesspit works in a fairly straightforward manner. All the wastewater from a property, including from the bathrooms, kitchen, and laundry, flows into the cesspit. The cesspit simply acts as a receptacle, storing the waste until it reaches capacity.

Because cesspits don't process or break down waste like septic tanks do, they need to be emptied frequently. The frequency depends on the size of the cesspit and the amount of waste being produced, but typically, a cesspit needs to be emptied every four to six weeks. This is usually done by a professional waste disposal company that pumps out the waste and transports it to a treatment facility.

What is The Purpose of a Cesspit?

The primary purpose of a cesspit is to safely store wastewater and sewage from a property until it can be properly disposed of. In rural areas of New Zealand where access to public sewage systems may be limited, cesspits provide an essential method for managing waste.

By securely containing the waste, cesspits help to prevent environmental pollution and protect public health. However, because they store raw sewage, they need to be monitored and maintained carefully to prevent leaks or overflows which could pose serious environmental and health risks.

Is a Cesspit The Same as a Cesspool?

In New Zealand terminology, a cesspit and a cesspool are essentially the same thing. Both terms refer to an underground tank or pit that is used to store wastewater and sewage from a property.

However, in some countries, the terms may have slightly different meanings. For instance, in the UK, a cesspool is a sealed underground tank that collects all wastewater, while a cesspit might refer to a rudimentary and often outdated system of waste disposal. But here in NZ, we generally use the terms interchangeably.

What is The Difference Between a Septic Tank and a Cesspit?

While both septic tanks and cesspits serve the purpose of managing waste, there are significant differences between the two systems. A septic tank is a type of onsite sewage facility that treats the wastewater through a process of bacterial decomposition and drainage. The waste flows into the tank where solid material settles at the bottom, and the remaining liquid is treated and then discharged into a drain field.

On the other hand, a cesspit doesn't treat the waste at all. It's simply a holding tank where all the waste is stored until it's pumped out and taken away for treatment elsewhere. This means cesspits need to be emptied much more frequently than septic tanks, usually every four to six weeks depending on usage and capacity.

What's The Difference Between a Cesspit and a Soak Pit?

A cesspit and a soak pit serve different purposes in the realm of waste management. As discussed, a cesspit is a holding tank for raw, untreated waste, which requires regular emptying. A soak pit, on the other hand, is a different beast entirely. It's a pit filled with coarse stone and gravel where water is directed to soak into the ground.

Soak pits are primarily designed to manage stormwater runoff, not raw sewage. They allow excess water to percolate naturally into the ground, reducing the risk of surface water flooding and groundwater contamination. So, while a cesspit stores waste for removal, a soak pit helps manage water levels and protect the environment.

What Are The Requirements For Installing a Cesspit NZ?

In New Zealand, there are strict regulations in place for the installation, maintenance, and management of cesspits to protect public health and the environment. The Building Act 2004 and the Health Act 1956 outline these requirements, which local councils enforce.

The Auckland Council, for example, states that cesspits must be designed and constructed to avoid any possibility of contamination of water supplies, and must be watertight to prevent leakage. They also need to be located at least 1.5 meters from any building and at least 50 meters from any water source. In addition, they need to be easily accessible for pumping out and maintenance.

As with any significant drainage repair or installation on your property, it's important to check with your local council for any specific regulations or guidelines in your area. And always hire a qualified New Zealand drainlayer for installation and maintenance to ensure that your cesspit meets all requirements and is safe for use.

In New Zealand, particularly in our vibrant city of Auckland, we're no strangers to managing water, especially stormwater. It's a task as necessary as it is intricate, demanding a good understanding of various systems and methods. Today, we'll shed some light on two of these systems - soak pits and soak holes, their workings, differences, benefits, and how they compare to septic tanks. Understanding these systems will help us effectively manage stormwater and contribute to the overall well-being of our environment.

Here at Real Drainlayers, we're always asked about the differences between soak holes and soak pits, how they work, what the benefits of each are, and more. Needless to say, we've spent a lot of time answering questions regarding soak holes and soak pits.

To better help you understand the differences and the benefits, we'll delve into the specifics of each system, highlighting the unique characteristics that make them suitable for different applications. Along the way, we'll explore the various regulations and guidelines that govern their use in New Zealand. By the end of this article, you'll have a solid understanding of soak pits and soak holes and their role in maintaining a sustainable water management strategy.

What is a Soak Hole?

A soak hole, often called a soakaway, is a type of drainage system designed to manage stormwater or surface water on a property. It's essentially a hole dug into the ground, filled with coarse stone or rubble, allowing water to percolate into the surrounding soil. They're a common feature in New Zealand's residential and commercial properties, particularly in areas with limited stormwater reticulation.

Soak holes are versatile and can be adapted to various site conditions, making them a popular choice for property owners. They're not only functional but also contribute to the overall aesthetics of the property by managing excess water and preventing unsightly puddles or waterlogging. By effectively managing stormwater, soak holes play an essential role in maintaining the health of local ecosystems and reducing the impact of urban development on the environment.

How does a soak hole work?

Similarly to a cesspit, soak holes work on the principle of gravity and percolation. When rainwater collects on your property - whether from your roof or other surfaces - it needs somewhere to go. With a soak hole, this water is directed into the hole, where it then slowly seeps or 'percolates' into the surrounding soil. This mechanism helps to manage the volume of stormwater, reducing the risk of flooding and waterlogging on the property.

The effectiveness of a soak hole largely depends on the characteristics of the soil in the area. Soils with higher infiltration rates, such as sandy or gravelly soils, are better suited for soak holes, as they allow water to seep through more quickly. Conversely, soils with low infiltration rates, such as clay or silt, may not work as well with soak holes, as they may take longer to absorb water or become saturated, leading to potential issues with stormwater management.

Soak Pit vs Soak Hole - What's the difference?

While the terms "soak pit" and "soak hole" are often used interchangeably, there are subtle differences. A soak pit is typically a covered, man-made pit filled with layers of rocks or porous material, and it is designed to disperse excess water into the ground. A soak hole, on the other hand, can be a natural or man-made depression in the ground where water collects and is absorbed.

The primary difference between the two lies in their construction and intended purpose. Soak pits are generally more structured and built with specific materials to facilitate water percolation. They are often used in urban settings or areas where controlled drainage is required. Soak holes, while similar in function, can be less formal and may occur naturally in the landscape. They are more likely to be found in rural settings or areas with less stringent stormwater management requirements.

What Are The Benefits of a Soak Pit?

Soak pits offer several benefits. They help manage stormwater, reducing the risk of flooding on your property. This role is crucial, especially in areas with high rainfall or inadequate public stormwater infrastructure. By preventing water buildup, they contribute to maintaining the structural integrity of buildings and other structures on the property.

Furthermore, soak pits provide an avenue for rainwater to percolate into the ground, thus helping to recharge groundwater levels. This natural replenishment of groundwater is essential for maintaining the health and sustainability of local ecosystems. In addition to their practical benefits, soak pits are also relatively easy to construct and maintain, making them a cost-effective solution for many property owners.

What is The Difference Between a Septic Tank and a Soak Pit?

While both septic tanks and soak pits serve to manage water, they are designed for different types of water. A septic tank is a part of the wastewater treatment system, designed to manage sewage from a property. The waste goes into the septic tank where solids settle, and the remaining liquid is treated and discharged.

On the other hand, a soak pit is designed to manage clean water, such as rainwater or surface runoff. It is not designed to handle sewage or wastewater. While a septic tank treats and discharges water, a soak pit simply allows water to soak into the ground. Both systems play vital roles in managing water on a property, but they serve very different functions and should not be used interchangeably.

What Are The Requirements For a Soak Pit NZ?

In New Zealand, particularly in Auckland, there are specific requirements for installing a soak pit. The Auckland Unitary Plan provides guidelines for the design and construction of soak pits. These guidelines include:

• The soak pit should be designed to manage a 10% Annual Exceedance Probability (AEP) rainfall event, with sufficient freeboard to contain a 2% AEP event without overflow.
• The soak pit must be located at least 5 meters from any building, 1 meter from any boundary, and above the highest known groundwater table.

These regulations are designed to ensure the safety and effectiveness of soak pits in managing stormwater. But the rules don't stop there. They continue:

• The soak pit must be filled with hardfill material, such as clean crushed rock.
• The dimensions of the soak pit - depth, diameter or width - should be based on the soil's infiltration rate, which can be determined through a soakage test.
• If the soak pit is deeper than 1.5 meters, it must be designed by a Chartered Professional Engineer.
• The soak pit must be covered and secured to prevent any accidental falls or entry of debris.

All these requirements aim to ensure that soak pits function optimally while ensuring safety. Non-compliance can lead to ineffective stormwater management, potential legal issues, and even structural damage to nearby buildings. It's always advisable to work with a professional when installing a soak pit to ensure that it meets all the necessary requirements and functions effectively.

In conclusion, soak pits and soak holes play a critical role in stormwater management in New Zealand. While they serve similar purposes, they are distinct in their design and application. Understanding these systems and the regulations that govern them is essential for any property owner or developer. Always remember to consult with a professional drainlayer or engineer - like those provided by Real Drainlayers - to ensure your soak pit or soak hole is designed and installed correctly, and is compliant with all relevant standards and regulations.