An overflow spillway is most often constructed as part of a gravity dam or a buttress dam. The spillway section is lower than the other sections of the dam allowing water to flow over its top and down its front face.

Carlow Precast have developed a precast concrete panel system to standardise the construction of the spillway channels and to provide a cost effective solution for AMP 6 projects. We can construct spillway panels with form line finishes where it is necessary to blend the structure with the local landscape.

Our DfMA solution is the most effective spillway solution available in the British Isles. Selected for value, durability, carbon, safety, and speed of construction. Our extraordinary portfolio of projects is only possible because our clients identified us as the best value solution to their requirements.


Why choose a Carlow Precast Spillway?

Useful information about Carlow Precast Spillways

Commonly asked questions about Carlow Precast Spillways

Why Carlow Precast Spillways?

Our unique blend of precast and in-situ elements maximises the benefit of off site fabrication, enabling the use of lower cost in-situ concrete in the most efficient manner. Our precast units typically represent 90% of the wall construction. The remaining 10% is greatly facilitated by our projecting reinforcement and formwork clamping system. This approach provides dimensional tolerance, self-healing capability and minimal thermal and drying shrinkage effects.

How can the Carlow Precast Spillway solution adapt to difficult site conditions?

We can achieve an architectural style and installation weight to suit the project landscape and terrain challenges.

What are the risks of so many joints in the wall system?

It’s not the joint that quantifies the risk but the distance between joints. This is what determines the thermal and drying shrinkage movement at each interface. In our construction approach the anticipated movement at each interface is typically 1/15th of that in a conventional joint. This significantly reduces the demand placed on the self-healing hydrophilic strip ensuring exceptional resistance to water penetration.


Even though elements are most cost effectively manufactured in Ireland, contracts are with our UK trading and therefore not sensitive to foreign exchange fluctuations.


For distribution through out the UK the most cost effective transport hub is Eastern Ireland. By accessing local ports along the western UK seaboard, tachograph constraints are significantly reduced.


Our designs and solutions are fully compliant with current BS, EN Client and water industry specifications (including CESWI).

Scope of design

We provide a complete design service for each project including both precast and in-situ elements. One point of responsibility, ensuring total performance guarantee.


We can provide supply only or supply and construct service allowing our expert customers to install their own Spillways.

Carbon efficiency

Our standard mixes contain up to 66% GGBS bringing enormous carbon efficiency to our products.


Our construction approach minimises the number of personnel and activities required to complete an installation.

How do you progress an enquiry?

Send us a briefing and we will organise for one of our technical team to email, phone or visit. We will bring our expertise and DfMA know how to help you identify and complete the optimum solution. We don’t charge at the project development stage.

Construction Programme

Typically 30 to 70% of the time taken to construct conventional in-situ structures. Major savings to be made on preliminaries and site costs.

Speed of manufacture and installation are of utmost importance and of course, our products must be cost effective and to the highest standards for the water industry. With these objectives in mind we have developed a precast modular spillway wall system to offer our customers a product that is to the highest standard and manufactured in an environment of rigorous quality control procedures.

All of our products are inspected at each stage of manufacture to ensure a high standard of finished product.

Included in our service pack is a full analysis and design to your site criteria. Our in-house designers will ensure national, international and customer specific standards compliance with professional indemnity insurance protection.

Included in our service pack is a full analysis and design to your site criteria. Our in-house designers will ensure national, international and customer specific standards compliance with professional indemnity insurance protection.

For more information about our Spillways/Cascades products and services please call our technical team on 0870 493 1408 or email us at .