Abstract: A collapsible concrete bulkhead is insertable into a framework. The bulkhead has a pivotable divider plate which is located juxtaposition to a bulkhead plate and moves laterally thereof to reside in an offset base portion of the framework. The bulkhead assembly forms separate concrete sections when concrete is poured into the framework and forms a gap when the bulkhead assembly is removed. Optionally, a liner can be inserted adjacent to the bulkhead assembly and the bulkhead assembly removed before full cure of the concrete so that the concrete fills the void left by the bulkhead with the liner separating the concrete sections.