The 900 Series — what is this?

For many years Iowa has used this series of numbers for unsigned state highways. Most of them were roads that they wanted to turn over to the appropriate county or city, but hadn't been able to do so yet. Some of them were short and isolated stubs of a few hundred feet, while others were longer routes that followed the new route of a US or state highway. Most of these routes were marked as "unmarked primary" roads on the state transportation map but appear on county maps, the Iowa Primary Road Sufficiency Log, the Iowa Detour and Road Embargo Map, and other DOT publications as well as some commercial maps (most notably DeLorme's atlas). In recent years unsigned state highways have been given numbers that are not in the 900s, such as IA 432, the former segment of IA 163 in Oskaloosa. (Exceptions are IA 904, a former segment of US 34 in Fairfield that was bypassed in 2008, and IA 961, a former segment of US 61 in Fort Madison that was bypassed in 2011.) More often than not, the unsigned 900-series numbers were recycled when a route which was originally given this designation was finally turned over.

In 1985 the first 900-series highway to receive markers was IA 965, a request made by the Johnson County Board of Supervisors. The Des Moines Register ran a story on April 23, 1988, on how a "No-Name Highway" in Woodbury County was confusing drivers. The "No-Name Highway," a former segment of IA 141, was designated as IA 982 but was not signed at that point. Three days later the Transportation Commission agreed to sign some of the unmarked primary roads in Iowa, including IA 982, within the next year. Other 900-series roads that received signs as part of this policy were IA 920, 925, 927, and 939. Signs for IA 931 and 945 in Polk County were put up in 2000. A few others were signed as rural street names (such as IA 941 in Hardin County), on freeway exit signs (such as IA 928 and IA 988), or on detour signs (such as IA 956 in mid-2002 or IA 923 in mid-2003).

In the spring of 2003 legislation was passed to allow the DOT to give 700 miles of state highways to counties and cities; the law took effect on July 1, 2003. This move wiped out almost all of the 900 series, including the handful of roads that were signed. The only survivors were IA 922, 926, 930, 934, and 946. IA 931 and IA 945 also survived, but they were transferred to Polk County in separate deals and most of the signs came down in August 2003. The last IA 945 markers were taken down in November 2003. Meanwhile, the transfer of part of IA 965 to the city of Cedar Rapids didn't become final until September 1, 2004. The segment of IA 965 between I-80 and US 6 in Coralville remains a state highway but is no longer signed.

This table lists the surviving 900-series highways as well as most decommissioned routes that are at least two miles long and had existed for at least ten years. (Four more decommissioned roads fit these criteria, but they are listed under the numbers that they replaced, as they were demoted to 900-series highways before they were finally turned over to local jurisdictions. IA 951, IA 966, IA 970, and the most recent IA 972 are listed under IA 95 (II), IA 416, IA 475, and IA 105 respectively.) A more complete list of known 900-series and other unsigned highways, including maps where they are available, can be found on Jeff Morrison's Super Secret Route Pages. The list includes two candidates for shortest state-maintained highway before July 1, 2003: IA 967 in Dubuque County near Farley and the remnants of IA 970 in Sioux City. Both of these routes were a whopping 0.04 miles long.

For the record, yes, there once was an IA 999. It existed after IA 333 near College Springs was relocated in 1968 (it was a spur from the new IA 333 to College Springs), but it was decommissioned in 1980.

All highways listed here were paved at the time of designation, so paving histories are not included with these listings.