Iowa One Call

Know what’s below.

Call before you dig.

811 / 1-800-292-8989


Iowa One Call was created in 1980 to improve communication between excavators and utility companies. As increasing amounts of underground facilities were installed, it became more and more difficult to determine where they were, and damage incidents were increasing. Concerned about the health and safety issues involved in many of these incidents, the Iowa Legislature mandated in 1993 that all utility companies join the One Call system, which in turn would be responsible for notifying every company which had facilities in the area in which work was being done. The law requires that everyone call this “One Call” number at least 48 hours (excluding weekends and holidays) before beginning any excavation. This system vastly simplifies the process of determining where it is safe to dig, since an excavator does not need to determine which companies have facilities in the area and deal with each company individually.

How It Works

Every utility company in the state of Iowa is required to provide One Call with a map of their underground facilities, and a 24 hour contact number. Everyone planning an excavation (which basically means putting anything into the ground, or disturbing it in any way) is required to call 1-800-292-8989 at least 48 hours before beginning excavation (excluding weekends and holidays). Callers will be asked for their street address, municipality or township & section number, and information about their project. They will then be given a ticket number which is their proof of compliance. The information will then be sent to every company on record as having facilities in the area, and the list of companies contacted will be given to the caller. Each company will then dispatch someone to mark their facilities. Once each company has responded, either by locating their facilities or indicating that the area is clear (or OK), the project may begin.

When To Call

Iowa law defines an excavation as much more than simply digging into the earth. Iowa One Call must be notified prior to any operation that may disturb or potentially disturb buried facilities. Excavators should not make any assumptions about the depth at which a facility may be buried.

Iowa law defines “Excavation” as an operation in which a structure or earth, rock or other material in or on the ground is moved, removed, or compressed, or otherwise displaced by means of any tools, equipment or explosives and includes, but is not limited to, grading, trenching, tiling, digging, ditching, drilling, augering, tunneling, scraping, cable or pipe plowing, driving and demolition of structures. “Excavation” does not include normal farming operations, residential, commercial or similar gardening, the opening of a grave site in a cemetery, normal activities involved in land surveying pursuant to chapter 114, operating in a solid waste disposal site which has been planned for underground facilities, the replacement of an existing traffic sign at its current location and no more than its current depth, and normal road or highway maintenance which does not change the original grade of the roadway or the ditch.

Types Of Locate Requests

NORMAL: As described above, the person doing the work must call in advance of the work and request that underground facilities be marked. Notification must be made at least 48 hours prior to all excavations. The 48 hours timeline will commence only during normal business days between the hours of 7:00 a.m. and 5:00 p.m. and does not include weekends or legal holidays (the 48 hours timeline on calls after 5:00 p.m. will begin at 7:00 a.m. the following business day). Excavators who do not make notification to Iowa One Call or do not wait the required 48 hours prior to excavating are in violation of the law and subject to civil penalties.

EMERGENCIES: In cases where life or property is at risk, an “emergency locate request” may be filed. In this case, companies will respond as soon as possible, regardless of the time of day of the request. There is no 48 hour waiting period, but excavation may not begin until each company has responded.

JOINT MEETS: In cases where an excavator wishes to explain the project before facilities are marked, they may make a “joint meet locate” request. In this case, they will set a time and place to meet, and each company will send a representative to meet with the caller. On large or complicated projects this may reduce confusion.

Indicating Project Location

When calling One Call, the excavator will be asked about the area in which they will be working.  Excavators are required to clearly indicate where the work will be done, preferably with white flags and paint, and to clearly explain this to the One Call center.   Failure to make this clear may delay the response to the locate request.

About The Marks

When locating personnel respond to a locate request, they will either mark their facilities in the area or indicate that they do not have anything buried in the area. This is often done by painting “OK” on the ground and placing a company flag to indicate which company has responded. If multiple companies respond and have nothing in the area, there may be multiple “OK”s or one “OK” with multiple company flags. This does not necessarily mean it is OK to dig, just that it is OK with that company. The excavator must correlate the responses with the list of notified companies to ensure that every company has responded before beginning excavation. If a company fails to respond within the 48 hours, or if there is a concern that some marks are in error or incomplete, the excavator should call One Call, give them the dig ticket number and explain the situation. The utilities will be notified of the problem and respond as soon as possible.

Each color of flag/paint indicates a type of facility. Orange is for telecommunication, blue for water, green for sewer, red for electric and yellow for gas. Since there may be two or more companies using the same color paint (eg: telephone and cable TV) flags are also used to indicate the company to which the facility belongs.

Once all of the facilities are marked, excavation may begin. Iowa law specifies that there is an 18″ “hand-dig” zone on each side of the facility. Within this area, excavation must proceed with extreme caution, since even hand-digging can easily damage most types of underground facilities. If there are any questions about the size, location or depth, One Call may be called again with a request for company personnel to be on-site during the work. Alternately, if the question involves KCTC facilities, excavators may call 656-3668 directly.

Hitting An Underground Facility

If an underground facility is damaged, it must be left exposed and reported to the owner of the facility. If there is any doubt about the owner, call One Call and report what has happened. They will notify all utilities that a facility has been damaged, and each company will respond, identify the facility and the owner will make repairs. Even “slight” damage must be reported, because if it is reburied it may become much more serious damage over time.