How weather affects wastewater

England’s climate is relatively mild, but as climate change has worsened, weather has become more and more extreme and unpredictable. The potential for extreme weather has been increasingly present in recent years with weather events like windstorms, heavy rainfall, floods, and droughts, all becoming more common and frequent. Additionally, the range of temperatures we experience in this country has also varied far more than it had historically.

But what affects might these weather patterns have on wastewater on-site?

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Heavy rain and storms

Increased surface runoff- Rainwater flowing over disturbed soil can carry pollutants into nearby drains or watercourses.

Erosion and sedimentation- Intense and frequent rainfall causes soil erosion on-site, leading to high levels of suspended solids in the wastewater. This can clog drainage systems and harm aquatic eco systems.

Flood risk- The increased volume of water can overwhelm underprepared sites. This is because temporary drainage or water management systems can be flooded leading to the uncontrolled discharge of untreated wastewater.

Ground saturation- Prolonged rainfall can leave the ground saturated, which reduces its capacity to absorb water, increasing the amount of surface runoff and making excavation and shoring difficult and hazardous.

Temporary dilution- Whilst heavy rain results in an increase in overall pollutants you must manage, the concentration of pollutants within wastewater can be diluted. This however, this is due to the higher volume of water, the level of pollutants have still increased.

Dry and hot weather

Increased pollutant concentration- With less water flow and higher evaporation rates, pollutants in stagnant or collected wastewater can become more concentrated.

Dust generation- Dry conditions create more surface and airborne dust. This can be washed into drainage systems during the next period of rain, known as a ‘first-flush’ of highly concentrated pollutants.

Odour issues- Higher temperatures in stagnant or low-flow water can increase biological activity and therefore the production of unpleasant-smelling and corrosive gasses such as hydrogen sulphide.

Freezing temperatures

Freezing and blockages – Water in pipes, drainage systems, or temporary storage can freeze causing blockages, pipe damage, or system failure.

Reduced treatment efficiency- Low temperature can slow down or stop, making treatment far more ineffective.

How can we help?

When the concentration of pollutants and suspended solids increases, you need a settlement tank you can rely on to avoid compliance issues and environmental harm when discharging. The WTS is a universal treatment tank with interchangeable lamella/coalescing media to suit all applications, and is considerably more effective than conventional settlement tanks. It’s an ideal solution when dewatering or dealing with stubborn suspended solids as the lamella/coalescing media encourages settlement of all types of silt.

What makes the WTS water treatment system more effective than conventional settlement tanks?

Firstly, we opt for PVC plastic instead of stainless steel for our media as it is more adaptable, easier to handle, and easier to clean. The composition of this media however, is where Kelly Tanks is really separated from alternatives. Most settlement tanks are plate settlers, but the WTS is a tube settler. in conjunction with its chevron shaping that ensures equidistant flow, the WTS creates an equal flow distribution so flow rate is consistent. This is due to tube settlers consisting of a higher number of smaller channels, with water being split between each channel, resulting in similar flow velocities which helps to prevent the flow short circuiting, the most common reason for inefficient treatment.

The system itself is simple and accessible, with no moving parts resulting in a robust system perfect for on-site conditions. Silt and sludge are collected in the hopper for easy removal.

But how can it handle the high volume of wastewater created by heavy rainfall?

We offer a large range of sizes and flow rates:

WTS- 15m³/hr

WTS XL- 25m³-hr

WTS XXL- 30-40m³/hr

WTS XXL LH- 50-60m³/hr

Multi Hopper - Up to 100m³/hr

But if you need to handle an even higher flow rate, our WTS systems are modular, and splitters can be provided to evenly distribute flow to multiple of our systems.

So, what are the benefits of an efficient wastewater solution?

• Achieve compliance

• Decrease operator intervention/Increased automation

• Reduce downtime

• Reduce effluent treatment costs

• Reduce waste disposal costs

• Reduce water consumption (through water recycling)

Get in touch today to see how we can help.