The extension to Mokelumne was abandoned in 1951. The remaining 32.4-mile branch continued to see limited freight service until 1972. That year flooding ruined the tracks in and immediately around Isleton so there was no need to keep the trackage. SP placed the trackage out of service between Walnut Grove and Isleton, and in 1977 the I.C.C. formally approve the abandonment of the 17.3 miles of trackage from Hood Junction and Isleton. By this time there were only two remaining active shippers on the branch, Stillwater Orchards and the end of the line at Hood, and the City of Sacramento sewage treatment plant at Del Rio which received occasional tank cars of chorine.

The end of the Walnut Grove Branch came with the final revenue run on 9/28/78. Then on Tuesday, Oct. 10. 1978 SD9Es SP4305 and SP4315 ran cab hop to Freeport and Hood Junction to gather up over 100 cars that sat in storage awaiting repairs at the Sacramento General Shops. It was all over under SP ownership.


The branch was later sold to CSRM for future excursion service.