I am about to be involved in the re-opening of a refurbished school swimming pool that has been closed for some years. Primarly for use by the school it will also be available to other users including groups and individuals for a fee. Chemicals will be delivered by road and unloaded onto the pavement. 

The Pool Water Treatment Advisory Group ...  code of practice says ....  Unloading (of chemicals0 should not be on the public highway. Where this is unavoidable local authority permission should be sought.

Does anyone know if this is something that is actually done in practice - it's not (as ffar as I  can see) a legal requirement in COSHH or anywhere else - but I wonder if there is something buried in Highways legislation - which is outside of my knowledge? If people do it - why? does this apply to deliveries of other chemicals to other industries? If not then why is there a specific requirement for pool water chemicals?

Local authorities are accountable to keep traffic moving - your delivery could impede the flow of traffice or passage of emergency services.

Road drains are intended for surface water ONLY and may for example run to a local watercourse so you need to know where any spillage could end up to put in place suitable control measures - check with your local water provider.

Depending upon the chemistry there could be issues with gasses being emitted

Have you discussed this re-instatement with Environmenatl Health given you intend to charge the public for access?