LONDON — Streets littered with potholes and garbage. Alcohol and drug treatment centers shut down. Vulnerable adults and children left without care.

That is the grim picture of Britain’s future painted by the County Councils Network, which warned on Thursday that local councils will be forced to slash more than $1 billion from their budgets next year in cuts that will very likely result in services being whittled to the bone.

Councils are Britain’s fundamental unit of local government, dealing with an array of basic needs: trash collection, public transport, libraries, town planning, caring for people in need, among other things. They levy a tax on homes and charge fees for some services. They also collect a nationally set tax on commercial real estate, and keep an increasing share of it.

But they are struggling to make ends meet, mainly because of a sharp reduction over the past decade in the central government funding that makes up a large portion of their income, at a time when a rising elderly population has strained local finances. At the same time, years of government-mandated caps on tax increases have made it hard for local authorities to replenish their coffers, forcing them instead to cut services.