A $650 million men's prison rising in Sioux Falls — the largest capital project in state history — B-21 Raider hangars at Ellsworth, two airport expansions, a Missouri River water system growing to 60 million gallons a day, and interstate rebuilds at both ends of the state headline South Dakota's public pipeline.
*How to read the total: the sum of the published figures in the list below. Bases differ by project — most are total cost estimates, some are federal grants, program totals, or construction contracts as awarded. Each project's expanded view labels its own basis. We add them up with the labels showing rather than pretend they're all the same kind of number.
Hover a pin for the project snapshot. Pin numbers match the project list below. Locations are approximate (nearest city or corridor midpoint) on a schematic state outline.
Click any project to expand its full record — description, owner, dates, funding, the law behind it, and its source. Filter by who owns it and where it stands, or sort by cost.
15 major public projects: 5 in Sioux Falls, 6 in the Rapid City / Ellsworth area, 2 in Vermillion, plus Brookings and Piedmont. The listed figures sum to ≈$1.6B. South Dakota's honest tally is modest — a majors list, not a long one — because this is a state of under a million people whose public builds with published figures above the $10M floor are concentrated in corrections, two airports, one air base, one regional water system and the interstate programme; smaller city and county work below that standard is not listed, and nothing has been padded to lengthen the page. One major South Dakota construction site does NOT appear as a record here by design: the far-site caverns of the Long-Baseline Neutrino Facility / DUNE at the Sanford Underground Research Facility in Lead. That project is listed once, on the Illinois page (record il-003), at the U.S. Department of Energy's CD-1RR total of ≈$3.3B for the combined Illinois–South Dakota project, and it is not double-listed here — the excavation and construction in Lead are part of that single record. Projects of South Dakota's nine tribal governments are likewise outside this page's owner rule (federal, state, university and municipal owners only) and are not listed, so that omission is visible rather than silent.
How the big pieces are counted: at Ellsworth AFB only discrete, individually priced MILCON contracts are tallied — the $135.5M phase maintenance hangar and the $33.5M shelter contract — and not the reported $1.5B-plus B-21 beddown programme total, which has no single published priced figure. At Lewis & Clark only the current, priced expansion phase (≈$150M, to 60 MGD) is tallied, not the $711M base system it expands. For the Sioux Falls men's prison the printed figure is the $650M the Legislature capped and approved in its 2025 special session for the Benson Road site; the abandoned Lincoln County plan's ≈$825M guaranteed maximum price, voted down in February 2025, is recorded on the project's own record, not in the tally. At Rapid City airport the two phases are listed separately at the airport's own August 2026 briefing figures ($70.6M and $121M), with Project 2 honestly marked pre-construction — its groundbreaking is expected in September 2027 and part of its federal share is requested but not yet received.
News-flagged sources: seven rows rest on news or trade-press reporting of official figures, flagged 'news-flagged' in the data — the prison groundbreaking (Argus Leader), the Lewis & Clark expansion and the Sioux Falls airport programme (South Dakota News Watch / Rapid City Post, from the airports' Aeronautics Commission presentations), the South Veterans Parkway segment (Associated Construction Publications, SDDOT figures), the USD fieldhouse (Government Market News, from HB 1137 and USD), the Ellsworth shelters (Business Wire, the contractor's USACE award announcement) and the SDSU residence hall (The Collegian, from a Board of Regents document). Each record names the underlying official source. The softest records on the page are the Binnewies Hall range ($14–16M, midpoint tallied, early-stage) and the fieldhouse's split figure ($40M authorised against a reported $45–50M total) — both are labelled as such on their records.
Deliberately excluded: projects completed in a prior year: the Pierre–Fort Pierre John C. Waldron Memorial Bridge replacement ($50M, opened March 2025), Sioux Falls' Water Reclamation Facility expansion ($215M — the largest infrastructure project in the city's history — completed October 30, 2025), South Dakota Mines' Nucor Mineral Industries Building ($41.8M, opened spring 2025), and the earlier South Veterans Parkway southern segment (≈$49.5M, substantially complete 2024). A verified termination: the Sisseton Milbank Railroad rehabilitation ($24M federal CRISI grant plus $6.25M state match) — in October 2026 the railroad told the State Railroad Board the business case no longer exists, and the board voted to terminate the funding as the railroad seeks to discontinue operations. Unfunded proposals, excluded and named: the Western Dakota Regional Water System pipeline to Rapid City (at least $3B, feasibility-study stage), the proposed eastern South Dakota water pipeline (at least $8.4B, study stage), Lewis & Clark's second expansion (about $2.47B, appraisal stage), SDSU's proposed Ness School of Management and Economics building (a fiscal-2028 funding request; no published total) and USD's planned Sanford School of Medicine relocation to Sioux Falls (about $150M, within the next decade, donor-dependent). The $84M RCP&E Freight Capacity Expansion is excluded as a private-railroad-led project on a privately owned line, notwithstanding its $22M federal RAISE grant and $20M state contribution. Also excluded as private by rule, however large: Sanford Health and Avera hospital builds (private nonprofits), Monument Health in Rapid City, and the state's proposed hyperscale data centres.