A flexible, water-permeable filter basket may be used to collect and remove debris from a sump in a drain-entry structure (e.g., a catch-basin). The filter basket includes a basket floor having a perimeter of substantially the same size and shape as a sump floor, at least one basket sidewall corresponding to at least one sump sidewall, and one or more handles collectively affixed to the at least one basket sidewall, the at least one basket sidewall collectively including a resilient frame. The filter basket may be used as a deformable sump insert to collect debris falling into a drain-entry structure for removal without use of a vactor truck.