Many types of utility services can be buried in the ground on your property. To avoid a potential accident caused by excavation, Iowa law requires that you have the location of all underground utility lines marked before digging by hand or with equipment. Hitting an underground utility line while digging can cause serious injuries, disrupt service to entire neighborhoods, and result in fines and repair costs. 

To comply with Iowa's One Call law, a homeowner or excavator must go online to or call 811 or 800-292-8989 to schedule underground utility lines to be located and marked. This will create a ticket for the location to be visited. The request should be made at least two days before starting any digging or excavating project, excluding Saturday, Sunday and legal holidays. Iowa One Call is a free service. 

After Iowa One Call is contacted, the following happens:

  • Operators who have underground facilities in the planned excavation area are notified. This includes natural gas and power utilities, communications companies, and city utility departments.
  • Within 48 hours of being contacted, utility representatives either mark their underground facilities with color-coded paint marks or flags or notify Iowa One Call that there are no lines in the area.

The color of flags or paint for marked utilities tells excavators what type of utility is in the area. The American Public Works Association (APWA) Uniform Color Codes for temporary marking of underground utilities are:

RED electric power lines, cables, conduit, and lighting cables
ORANGE telecommunication, alarm or signal lines, cables, or conduit
YELLOW natural gas, oil, steam, petroleum, or other gaseous or flammable material
GREEN sewers and drain lines
BLUE drinking water
PURPLE reclaimed water, irrigation, and slurry lines
WHITE proposed excavation limits or route
PINK temporary survey markings, unknown/unidentified facilities

One Call Complaints and Violation Enforcement 

The Office of the Attorney General enforces the One Call Law. You can file a One Call Complaint using the Attorney General's online complaint form.

Iowa One Call Damage Prevention video  

IUB 2021 One Call Law and Damage Prevention Survey

IUB Safety and Engineering surveyed excavators, operators, contractors, and other stakeholders in 2021 as part of the IUB Damage Prevention Program. Survey results helped the IUB better understand the reasons for noncompliance with Iowa's One Call law, which protects underground utility infrastructure. The survey also provided educational resources to excavators, contractors, locators, and others about Iowa's One Call process. 

Survey Results: Iowa's One Call Process Assessment and Learning Aid  

More Information

News release: IUB Promotes National Safe Digging Month, protecting underground utilities
Informational Handout: Iowa's One Call Law 
Iowa One Call - Schedule a utility locate or manage existing locate tickets
Common Ground Iowa - Educates industry members on damage prevention practices 

Damage Prevention and One Call Contact 

IUB Safety and Engineering
Kevin Yearington, Manager