Case Studies
What A Sustainable Business is Built On: Clark-Drain and DS Smith’s Paper Mill

At a Glance:

  • New build paper mill extension required high-performance drainage channels
  • Large surface area and high-volume water discharge posed a challenge
  • Heavy machinery and forklift traffic placed high load demands on channels and covers
  • Clark-Drain’s range of 200mm channels with F900 (90-tonne) rating was chosen for the job
  • Polymer concrete channels combine corrosion resistance and low permeability, for maximum hydraulic performance and reliability

The Client

DS Smith ( is a leading provider of sustainable packaging solutions, paper products and recycling services worldwide. One of the largest companies listed on the London Stock Exchange, it operates in more than 30 countries, employing over 30,000 people, and provides customers with strategic support across their entire packaging supply cycle.

The Challenge

DS Smith’s now-completed paper mill facility in Sittingbourne, Kent, produces paper and packaging materials used in every sector from transit and transport, to retail and ecommerce, to consumer packaging, and more, by businesses across the world.

But although the company has invested heavily in increasing manufacturing efficiency and reducing waste, this new building inevitably still needed to drain high volumes of water, over a vast area, at speed. 

Logically, this pointed to a need for more and larger drainage channels, but there was an additional complication: the channels needed to be able to stand up not only to the constant, high-volume flow of water, but the combined weight of heavy machinery and forklift traffic passing over them.

Ultimately, it was a question of finding the optimum balance between the size, footprint, cost, and hydraulic efficiency of the channels chosen, their long-term resilience to constant wastewater throughput, and their ability to stand up to punishing surface loads.

The Solution

Before the installation began, Clark-Drain went to site and completed a take-off to assist the contractor, N P S Building and Civil Engineering, and ensure their needs regarding materials and quantities were understood and correctly met.

The contractor selected Clark-Drain’s 200mm polymer concrete channel (CD F20) range for the project, with stepped fall and F900 slotted gratings, all supplied by Jewson Limited, Sittingbourne.

Deployed in four different size variants on the site, with maximum throughflow ranging from 19.9 litres per second to 44.4 litres per second, this tough channel solution is constructed from polymer concrete for maximum corrosion resistance and low permeability, and is edged with ductile iron and topped with ductile edge F900-rated slotted gratings, producing a unit that can withstand weights of up to 90 tonnes.

Designed, tested and certified to BS EN1433:2002, the channels deliver large internal capacity relative to their external dimensions – maximising throughput – and are quick and easy to fit, thanks to their unique “CatchLock” retention mechanism.

Outcomes and Results

The Clark-Drain drainage solutions chosen for this project fully addressed the customer’s critical technical requirements for hydraulic efficiency and load-bearing capability, enabling the contractor to deliver a drainage system that made it possible for DS Smith’s new facility to operate as envisaged, despite the challenges.

At the same time, those same solutions’ cost-effectiveness and ease of installation were well suited to the contractor’s own budgetary and operational requirements, delivering optimum outcomes for the contractor and end-customer alike.

For more information on how Clark-Drain can help your business deliver cost-effective drainage, no matter how big, small, or technically challenging your project, get in touch.