Law Enforcement Agencies in Waterloo, MD MD › Howard County Agencies serving the city of Waterloo in MD. Agency Types in Waterloo Adult Institutions 5 agencies County Jails 1 agencies State Police 1 agencies All Agencies in Waterloo, MD Howard County Department of Corrections Howard County Jessup Correctional Institution Howard County Maryland Correctional Enterprises Howard County Maryland Correctional Inst Jessup Howard County Maryland Corrections Pre-Release System Howard County Maryland State Police Howard County Patuxent Institution Howard County
