Surfaces for water parks and splash pads: planning points for designers and operators

A practical guide to planning, specifying, accepting and maintaining exposed-aggregate finishes in busy water-play areas, covering slip resistance, drainage, wet–dry zones, water care, cleaning and records.

An exposed-aggregate finish can give water parks and splash pads a continuous, themed surface. However, its suitability for each zone must be confirmed for the project, not assumed, and slip resistance, drainage and exposure to repeated wetting and drying all need to be settled in the specification. The finish is decorative: it is not structural repair or waterproofing, and it cannot make a play area safe by itself.

Why water-play surfaces need their own brief

A water-play area is used very differently from a private pool. Children run, sit, crawl and slide on it. User numbers are high, operating hours are long and sunscreen builds up quickly. In tropical and hot climates, strong sun and heavy rain add further stress.

At the start, the design team, operator and applicator should agree a brief for each zone:

• the intended use (swimming, wading, spray play, walkways, seating)
• whether the zone is permanently submerged, partly wet or drained between cycles
• the substrate, waterproofing and responsible party
• cleaning, water-treatment and inspection arrangements

Share this brief with PebbleCrete to discuss material selection and the relevant technical information. Suitability for each area should then be confirmed through the project team.

Slip resistance as a project requirement

Treat slip resistance as a requirement written into the specification, not as a property of a material name. Aggregate type alone does not determine grip, so assess the surface by representative testing for the intended use and conditions.

A clear requirement states:

• Which areas are covered, and whether they are wet barefoot, shod or mixed-use zones
• The test method, chosen by the project team from recognised published methods to suit local requirements and use
• The acceptance criterion, and who sets it
• What is tested: a laboratory sample, an on-site mock-up or the installed surface
• Who carries out the test, and when

A test result applies only to the surface and conditions tested, so read it with its stated limits. Deposits, wear and cleaning change a surface over time. Include periodic re-testing in the operator’s risk assessment.

Comfort matters as well as grip. Where children sit or crawl, check texture and edges on a wet mock-up, not just on a dry sample.

Drainage, falls and repeatedly wet areas

The finish follows the geometry of its base, so falls, levels and drainage belong to the preparation stage. Ponding can create slip hazards, leave deposits and encourage biofilm. Resolve it in the base before finishing begins.

Some locations behave very differently from a continuously submerged pool floor:

• zero-depth splash pads that drain between play cycles
• beach entries and shallow approaches
• overflow lips, channel edges and water-feature walls
• deck areas within the spray zone

Confirm suitability for each of these individually. PebbleCrete’s guidance is that beach entries and lagoon shallows must be designed so the finish stays continuously wet. If a splash pad will regularly dry out, raise this with the pool designer and supplier before specifying. Confirm suitable construction details for each exposure condition. Where suitability cannot be confirmed, consider a different surface altogether.

In strong sun, a dry surface can become warm underfoot, and darker colours may make this more noticeable. Include this in the design review.

Coordinating play equipment, fixings and edges

Water-play areas have many penetrations: spray nozzles, base plates, anchor fixings, drains, grates, lights and sometimes fibre-optic points. Coordinate all of them before the finishing visit.

• Set fixings and housings at levels that allow for the full finish build-up, not only the nominal 10 mm finish, so that covers and grates still fit.
• Detail edges at fittings to avoid projecting corners or sharp changes in level.
• Have the designer specify movement joints and transitions to tiles, decks or other surfaces for the agreed construction system.
• Agree service access to concealed lighting and pipework, and show the routes on the handover drawings.

Any equipment added later needs its own assessment for that project, and a local repair may remain visible.

Colour and theming with a continuous finish

A continuous finish can follow curves, channels and shaped features, which suits themed designs. Several blends can mark out zones, form patterns around spray features and highlight changes in depth or step edges. These decorative patterns add to the project’s required safety markings and signage. They do not replace them.

Sugar Marina Lagoon Splash Park in Phuket, for example, uses several PebbleCrete Classic colours. Garden City Water Park in Phnom Penh combines PebbleCrete Classic and PebbleCrete Glass. Photographs show only the general character. They do not confirm the exact specification of every surface or how it was installed.

Appearance changes with water depth, sunlight and viewing angle, and shallow areas usually look lighter than deeper ones. On every project:

• review a current physical sample wet, and also dry where a pad is often seen dry
• approve an on-site mock-up
• record the family, colour and sample reference
• discuss batch planning before the application visit

Some variation is part of a hand-applied finish. Assess it against the approved sample, the mock-up and the project’s acceptance criteria. Investigate any marked irregularities with the applicator.

Water treatment and cleaning regimes

Commercial facilities must follow local health requirements for disinfection, testing frequency and record-keeping. The values below are care targets for a PebbleCrete finish. Coordinate them with the treatment system, the approved care guidance and those requirements. Where local requirements differ, they take precedence. Raise any conflict with the supplier at design stage.

• pH: 7.6–7.8 requested
• Total alkalinity: 80–120 ppm
• Calcium hardness: 200–400 ppm

Read these values together, not one at a time. Aggressive water etches the cement matrix. This roughens the surface and can eventually loosen aggregate, which affects comfort and grip as well as appearance.

Never add chlorine directly onto the finish, in any form. Dose it into the balance tank so that it is diluted and circulated first.

A new finish needs to stay under water during its approved start-up programme. Where a surface cannot be kept under water during start-up, confirm suitability with PebbleCrete before specifying. Test the filling water before the application date.

Agree a written cleaning regime with the operator, covering:

• daily debris removal, brushing and rinsing
• sunscreen residue and biofilm in wet–dry zones
• whether cleaning products are compatible with a cement-based surface

Strong acid and aggressive abrasion are not routine maintenance. If a stain keeps returning, investigate the cause rather than using stronger chemicals or more abrasion.

Inspection and records

At handover, keep the approved sample and mock-up reference, the material family, colour and batch details, and the start-up record. Also keep drawings of fittings and concealed routes, and slip-resistance evidence with its stated limits.

During operation:

• Daily walk-round: check for ponding, damaged fittings, sharp edges and loose aggregate.
• Periodic inspection: look for roughness, deposits, cracks, hollow-sounding areas and joint condition, and take photographs recording the date and location.
• Water log: record readings before treatment, the products and amounts added, and the follow-up reading.

As a planning figure, an exposed-aggregate pool finish is generally expected to serve for 15–20 years. This is an industry estimate, not a warranty term. Where an individual pool falls within or outside that range depends on substrate preparation, application quality, water chemistry and routine maintenance.

Wet–dry areas such as drained splash pads need individual assessment and should not be planned on that figure alone.

Frequently asked questions

Photographs and screen colours are illustrations. Confirm colour and texture with a current physical sample viewed wet and an approved on-site mock-up.

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