An iconic square

The largest pedestrianised square in the European Union
An iconic square

Do you know this square shown in the pictures? 

It is the largest pedestrianised square in the European Union, and the second largest in the continent of Europe. We are talking about the famous Plaza del Pilar in Zaragoza, Spain. 

Today we're bringing you a new drainage solution that we developed specially for Plaza del Pilar.

For this project, which could not be more iconic, they renovated the square using drainage solutions from ULMA.

Before the renovation work, they had grooved flagstones and drains with cast iron grating for maintenance.

This time they needed a system that could withstand D400 loads as, even though it is a pedestrianised square, it is also a hub for events in the city. During the Fiestas del Pilar, for example, stages are erected where all the concerts are performed, so trucks will need to be able to pass through the area.

And in terms of aesthetics, the appearance needed to remain the same, to maintain the beauty of the square.

That is why we used our hidden drainage system with single-slot grating, a channel and an accessible sump unit, that you can see here: 

But there was one problem: the owner did not want the manhole for the sump unit to also be slotted, instead they needed to fit cast iron grating on it, to retain the original appearance of the square.

To do this we designed an alternative manhole.

Bespoke solution

We made a special support with a unique box at the right height to ensure that the slotted grille and the slotted manhole were at the same level.

In the photos you can see the solution that was installed at Plaza del Pilar.

There were height restrictions in the area because there is a car park just below, so the low-profile SM300 channels were used. 

And for the areas with no height restriction, a drainage solution was installed that provides increased hydraulic capacity and offers savings in terms of cleaning and maintenance time: the F250K channels with a mixed slope of 2.5%.


Because they wanted to increase the water flow and achieve a self-cleaning effect, thus reducing maintenance. This was a major factor for the Zaragoza City Council. They installed the F250K with lateral slots to achieve the elegance and appearance of a hidden drainage system, while also increasing the hydraulic capacity of the channels. 

If you'd like a quote or just more information, click here.

Slope of 2.5%

Well, as you can see, these channels with a built-in slope from ULMA are the only option on the market with an actual slope of 2.5%.

This noticeable slanted design increases the hydraulic capacity as the slope causes the water to flow faster. 

And thanks to this increased speed, more water is drained, achieving the same effect as with larger channels.

It also offers savings in terms of cleaning and maintenance because as the water flows by it takes with it the built-up sediment, thus achieving a self-cleaning effect.

This is a major selling point for any large project, such as this one at Plaza del Pilar.

Now you can see how capable our engineering department is at creating bespoke solutions to meet the needs of your projects.




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