DRAINAGE DOES NOT ALWAYS HAVE TO MEAN REMOVAL

When we talk about drainage, it is easy to imagine a simple journey: rain falls, water reaches a drain, water leaves the garden. Sometimes that is exactly what needs to happen.

But drainage can also be about controlling the journey rather than simply shortening it.

Could some water safely enter the soil? Could planting use it? Could it be temporarily held or allowed to move more slowly through the garden before it leaves?

These questions do not replace drainage. They change the way we think about what drainage is supposed to achieve.

A GARDEN CAN NEED LESS WATER AND HOLD MORE WATER AT THE SAME TIME

During wet periods, we work hard to remove water. During dry periods, we bring water back into the same garden.

That does not mean a garden should simply retain as much rainwater as possible.

Holding water and waterlogging are not the same thing. The aim is to give useful water somewhere appropriate to go, not to keep every drop.

SOIL IS PART OF THE RAINWATER SYSTEM

When thinking about rainwater, it is tempting to focus on visible drainage: channels, gullies, pipes and outlets.

But one of the largest potential stores of water in a garden is already there: the soil.

Healthy, well-structured soil can receive and hold water differently from ground that has been heavily compacted or disturbed during construction. That matters not only during wet weather but during dry periods as well.

Construction can change the way soil behaves. Machinery, excavation, storage of materials and repeated foot traffic can all affect the ground beneath the finished garden.

So when we think about rainwater, we also need to think about what has happened to the soil that is expected to receive it.

HARD LANDSCAPING AND RAINWATER MANAGEMENT DO NOT HAVE TO BE OPPOSITES

A well-designed patio can be an entirely appropriate part of a garden. What matters is what happens to the water that reaches it.

Does all of that water need to enter a drainage system immediately, or can some be directed towards an area of the garden that can safely receive it?

The patio, lawn, planting, soil and drainage can be considered as parts of one water system rather than separate features.

SOMETIMES THE BALANCE IS ALREADY PART OF THE PLANNING CONVERSATION

Across London, planning requirements and local policies can influence the balance between hard surfaces, planting and areas capable of managing rainwater.

A client may want a generous patio, a garden room, paths, seating areas and other practical surfaces. Each may make sense individually, but together they begin to change how much living and permeable space remains.

This does not mean hard landscaping is wrong. It means the effect of all those decisions should be considered together.

NOT EVERY GARDEN SHOULD HOLD WATER IN THE SAME WAY

There cannot be one rainwater solution for every London garden.

Soils differ. Levels differ. Some gardens sit higher than neighbouring properties and others lower. Buildings, basements, retaining walls and boundaries can completely change what is sensible.

In one garden, allowing more water into planted ground may work very well. In another, deliberately concentrating water in the same way could create a problem.

The objective should never be to hold water simply because holding water sounds environmentally better.

We need to understand where that water will go next.

PLANTING CAN BECOME PART OF THE INFRASTRUCTURE

Planting is usually discussed in terms of appearance, habitat, privacy, seasonality or atmosphere. But planting areas can also perform practical work.

Their soil can receive water. Plants use moisture. Their roots influence soil structure.

That means the planted parts of a garden are not necessarily separate from its drainage strategy. In the right conditions, they can be part of it.

KEEPING RAINWATER CAN ALSO MEAN USING FEWER RESOURCES

Holding water does not only mean allowing it into the ground. It can also mean storing some of it for later use.

But storage needs the same level of thought as any other part of the drainage system.

The amount of water available, the area collecting it, how quickly storage fills, how the water will be used and what happens when the storage is full are all part of the same system.

A full water butt or storage tank cannot continue receiving unlimited rainfall. Overflow still needs somewhere appropriate to go.

During dry periods, however, water collected when it was abundant can reduce the need to use mains water for planting.

THE ANSWER MAY BE DIFFERENT DURING DIFFERENT KINDS OF RAIN

Not all rainfall places the same demands on a garden.

A long period of moderate rain gives the ground time to respond differently from a short, intense downpour.

A garden may be capable of receiving and using a useful amount of ordinary rainfall while still needing a safe overflow route for more extreme conditions.

Holding more rainwater does not mean pretending overflow will never happen.

It means understanding what the garden can manage before that overflow becomes necessary.

WE CAN DESIGN AROUND WATER RATHER THAN ADD DRAINAGE AFTERWARDS

Water is easier to consider while the garden still exists as a plan.

A level might direct water towards planting rather than away from it. A lower planted area might have a deliberate purpose. A rainwater storage system could be incorporated before the finishes make access difficult.

These decisions are much easier to make before patios, walls, lawns and planting have fixed the final levels of the garden.

PERHAPS THE QUESTION IS NOT HOW QUICKLY WATER CAN LEAVE

London gardens still need drainage. Buildings need protection. Patios need to function. Excess water needs somewhere safe to go.

What we can question is the assumption that successful drainage always means removing rainwater from the garden as quickly as possible.

Sometimes the better question is what the garden can safely do with that water before it leaves.