This is the third part of a three-part technical report about the Uppsala testbed part of the NorDark research project. The earlier two reports contain the corresponding information based on the existing outdoor lighting installed at the testbed site in Sävja, Uppsala (Dincel, 2023; Dincel 2024). Part One discussed the method and procedure of collecting data as well as illuminance and luminance levels by hand-held and HOBO sensor devices under different sky and weather conditions. Part Two complemented the first part by including spectral power distribution (SPD) and correlated colour temperature (CCT) values of the same conditions recorded by hand-held spectrometer devices and wearable LYS button sensors. This part focuses on outlining the measured results of illuminance and spectral properties after an outdoor lighting intervention was implemented at the site. The post-intervention measurements described here were conducted on specific days within a timeframe during the period of November 2023 and January 2025.