# Water treatment, reuse, consumption

Part ID: 6.06 · Layer 6 (Facility cooling & HVAC)

Chemical treatment, filtration, and reuse systems that condition make-up water and manage the water a facility's cooling system consumes or discharges.

Applies to both the closed facility water loop (6.05) and, where wet cooling towers are used, the open evaporative loop (6.02): treatment prevents scale, corrosion, and biological fouling in closed loops, while reuse and consumption management address the water lost to evaporation in wet heat rejection. Data center water consumption has become a public and regulatory flashpoint as campuses grow, pushing some operators toward water-free (dry, air-cooled) heat rejection at a cost premium and others toward reclaimed or non-potable water sources that cut fresh-water draw without giving up evaporative cooling's efficiency. Municipal supply and reuse arrangements are inherently site-specific, so the investable exposure sits less in who controls a given site's water and more in the vendors of treatment chemistry, membranes, and reuse or reclaim equipment that let a wet-cooled site use less fresh water per unit of heat rejected. Investors should watch permitting timelines tied to water use as a growing schedule risk alongside the power-side bottlenecks in Layers 7 and 8.

**AI delta:** AI campuses' scale and continuous operation have made cooling-water consumption a public and regulatory issue in a way conventional data centers rarely triggered, pushing sites toward reclaimed or reuse water, treatment that extends closed-loop cycles, or water-free heat rejection.

## Companies

| Company | Role | Confidence | Ownership | Ticker | Note |
|---|---|---|---|---|---|
| ChemTreat | manufacturer | inferred | subsidiary |  | with Danaher |
| DuPont | manufacturer | inferred | public | DD | membranes |
| Ecolab (Nalco) | manufacturer | inferred | public | ECL |  |
| Kurita | manufacturer | inferred | public | 6370.T |  |
| Pentair | manufacturer | inferred | public | PNR |  |
| Veolia | manufacturer | inferred | public | VIE.PA | Water Technologies |
| Watts | manufacturer | inferred | public | WTS |  |
| Xylem | manufacturer | inferred | public | XYL |  |
| Gradiant | manufacturer | inferred | private |  |  |

Confidence tags: disclosed = company/filing statement; reported = trade press or partner list; inferred = taxonomy lead.