Do ‘dig once’ and permitting policies improve fiber availability?

State and local governments have enacted different types of legislation aimed at improving broadband availability. Two unstudied policies of interest are: (1) “dig-once” policies requiring state-funded construction projects to notify local internet providers about the opportunity to bury conduit for easier wire installation in the future, and (2) permitting policies requiring an expeditious response from local jurisdictions regarding the installation of broadband equipment. We use the example of Iowa, which passed legislation on both of these topics in 2015 and compare trends in fiber broadband availability with that of states who did not pass such legislation. We also consider the potential impact on fixed wireless availability, which largely depends upon a fiber middle mile. We use coarsened exact matching at the census tract level to construct treated and control groups with similar pre-2015 demographic characteristics and broadband availability trends in Iowa and other states. Difference-in-difference regression analysis with the matched samples then assesses the policy impact on fiber and fixed wireless availability post-implementation. The results suggest that Iowa's policies increased fiber broadband availability by 2.4%–6.6% when considering eight model specifications which account for different criteria such as geographic region, other (non-dig-once or permitting) broadband policies, and federal funding received. The policies do not appear to have any effect on fixed wireless availability.