Identify the pavement system first
Permeable interlocking concrete pavement, or PICP, uses stone-filled joints and underlying aggregate layers to admit and manage water. It is a different system from conventional sand-jointed pavers.
CMHA's maintenance guide, revised in 2020, addresses that drainage function. Before borrowing a routine cleaning or re-sanding specification, establish which system is actually installed.
Plan for sediment recovery and joint material
CMHA explains that power washing alone is generally not the best approach: suspended sediment can return to the pavement before it is recovered. Washing can also displace jointing aggregate that needs replenishment.
The guide distinguishes routine maintenance from restorative work. Removing loose material before it becomes lodged is a different task from recovering accumulated sediment and affected joint material. A cleaner-looking surface does not answer every maintenance question.
Look beyond the top of the pavers
FHWA's April 2019 technical brief recommends reviewing maintenance records, photographing conditions and noting sediment sources. Its inspection list includes ponding, settlement, cracked pavers, surrounding soil or vegetation and the drainage outlets present in the system.
Those observations help inform the maintenance plan and whether remedial work is needed. They provide a broader starting point than selecting equipment solely from the pavement's appearance.
Turn the assessment into a clear scope
WashWiki's practical suggestion is to ask for the installation records and any existing maintenance plan before requesting a bid. Then have the proposed scope explain how debris will be recovered, what happens to displaced joint material, and who will assess drainage concerns or damaged areas.
Agree on the condition records and follow-up checks the owner will receive. Use the pavement's design, condition and applicable guidance to determine the plan; this article does not prescribe one pressure setting or maintenance interval for every site.
The references are established technical guidance, not an announcement of a new rule. Their value is helping the owner and contractor define the actual job.
Sources & references
- Maintenance Guide for Permeable Interlocking Concrete Pavements — PAV-TEC-023-20, revised 2020 — Concrete Masonry & Hardscapes Association. Checked October 26, 2026.
- Permeable Interlocking Concrete Pavement — FHWA-HIF-19-021, April 2019 — Federal Highway Administration. Checked October 26, 2026.