I am in charge of constructing a website with a '2-dimensional' site map, as explained later.

I am looking for (preferably a Wordpress plugin, as the site is built in Wordpress already) that would make managing thousands of pages a lot easier.

To explain further, let me iterate my situation. I am building a website for a construction company, and they have several key cities and several key services. Now, they want a parent page for each service, and another unique page for the child sub-service, and finaly, a grandchild page for the city they are performing the service in.

For example, if they were doing Concrete Construction in Los Angeles, the URL would look like:

/concrete/construction/los-angeles

The content on /los-angeles would be the same as on /malibu, or /burbank.

However, there would be a different set of content for /concrete/design/los-angeles, but the entire page content (sans a few variables with city names) would be the same.

Is there a way to manage or automate 'matrixing' this information on the site? I am looking for a tool that would allow me to easily add a 'city' with the same content across all grandchildren, per the child's content requirements. All of the grandchildren pages will have redundant content across them.

Should something like this not exist, how difficult would it be to create, as a freelance side project? I need a tool like this, because I am approaching about ~500 cities and 50 services (Concrete Construction, Concrete Design, Concrete Engineering, etc)