Introduction

James and Lori Marlowe, homeowners on Highway 378 in Florence County, South Carolina, experienced two catastrophic floods—October 2015 and Hurricane Matthew in October 2016—while a major road-widening project by the South Carolina Department of Transportation (SCDOT) was under construction adjacent to their property. The Marlowes sued SCDOT asserting claims for inverse condemnation, conversion, due process violations, and negligence. After summary judgment for SCDOT at the trial level, the South Carolina Court of Appeals reversed summary judgment on inverse condemnation and held that SCDOT was not immune under the Stormwater Management and Sediment Reduction Act. On certiorari, the Supreme Court of South Carolina reaffirmed that the Stormwater Act does not confer immunity but reinstated summary judgment on inverse condemnation for lack of proof that SCDOT’s construction “most probably” caused the plaintiffs’ flood damages.

Key issues:

• Does the Stormwater Management and Sediment Reduction Act immunize SCDOT from liability?
• Can the Marlowes establish an inverse condemnation claim by showing SCDOT’s roadway construction “most probably” caused their flood losses?

Summary of the Judgment

The Supreme Court unanimously held:

1. Section 48-14-160 of the Stormwater Management and Sediment Reduction Act neither imposes liability nor grants immunity to SCDOT in this context; summary judgment on that ground was improper and is reversed.
2. The inverse condemnation claim must be dismissed because the Marlowes’ expert could only testify that the construction possibly contributed to the flooding, not that it most probably caused the floods. Under South Carolina law, causation in inverse condemnation requires a probability standard beyond mere possibility.

Analysis

Precedents Cited

• Ray v. City of Rock Hill, 434 S.C. 39 (2021) – Defines inverse condemnation elements and holds mere inaction is insufficient; requires an affirmative, positive, aggressive act by the government causing the loss.
• Hawkins v. City of Greenville, 358 S.C. 280 (Ct. App. 2004) – Clarifies that the plaintiff must show the government’s acts caused or precipitated flooding; lack of causation warrants summary judgment.
• Baughman v. AT&T, 306 S.C. 101 (1991) – Establishes the “most probably” rule for expert testimony on causation in tort and condemnation claims.
• Clark v. Greenville County, 313 S.C. 205 (1993) – Applies the probability standard and excludes expert opinions based on mere possibilities.
• Marlowe v. S.C. Dep’t of Transp., 441 S.C. 319 (Ct. App. 2023) – Court of Appeals decision reversing summary judgment on inverse condemnation and rejecting statutory immunity under the Stormwater Act.

Legal Reasoning

Stormwater Act Interpretation: Section 48-14-160’s plain text neither creates liability nor shields state agencies from liability arising from land‐disturbing activities. The Court emphasized that the statute’s two subsections are independent: one prevents implying new liabilities; the other preserves existing duties and obligations, thus leaving SCDOT’s common‐law causes of action intact.

Inverse Condemnation Causation Standard:

1. Elements: (1) affirmative, positive, aggressive act by government; (2) a taking of private property; (3) public use; (4) permanence; and (5) causation linking act to damage.
2. Summary judgment on inverse condemnation is proper if no genuine dispute exists on any element, including causation.
3. Expert opinion on causation must satisfy the “most probably” rule—not mere possibility—to be admissible and to raise a triable issue of fact. The Marlowes’ engineer testified only to a “possibility” that project design “may have” prevented or reduced flooding. Such equivocal testimony cannot sustain an inverse condemnation claim under Baughman and Clark.

Impact

This decision clarifies two critical points:

• Government agencies in South Carolina remain liable under common law for water-related property damages notwithstanding the Stormwater Management and Sediment Reduction Act.
• Plaintiffs pursuing inverse condemnation must secure expert testimony that the governmental act most probably caused their injury. Opinions couched in terms of “may have” or “possible contribution” are legally deficient.

Complex Concepts Simplified

• Inverse Condemnation: A lawsuit against a government agency for effectively “taking” property without formal eminent-domain proceedings, e.g., by flooding or severing access.
• “Most Probably” Rule: Expert testimony on causation must show that something is more likely than not (>50%) caused the harm, not simply that it might have.
• Return Interval: A statistical measure of how often a certain magnitude of rainfall or flood is expected to recur (e.g., a 1,000-year storm).
• Summary Judgment (Rule 56(c), SCRCP): A procedural device allowing courts to decide a case when no real dispute of material fact exists.
• Stormwater Act Immunity: The question whether a statute granting or limiting regulatory authority also protects government actors from lawsuits.

Conclusion

The Supreme Court’s decision in Marlowe v. SCDOT resolves two pivotal issues:

1. The Stormwater Management and Sediment Reduction Act does not immunize state agencies from liability for damages resulting from their land‐disturbing operations.
2. Inverse condemnation plaintiffs must provide expert proof that the government’s affirmative act more likely than not caused their loss; speculative or possible‐only opinions cannot defeat summary judgment.