Microsoft SAT82 Castroville Data Center Watch

Microsoft's SAT82 filing at 18844 FM 1957 in Castroville, Texas gives LVN a clean Medina County data-center watch item with a source-backed construction window. The Texas Department of Licensing and Regulation record lists Microsoft Corporation as owner, WSP USA Inc. as design firm, a one-story data-center building with five colos, 244,676 square feet of gross building area, a $482.6 million estimated cost, an April 11, 2026 start date, and a February 8, 2028 completion date.

The broader operator context is also source-backed. Microsoft Local says Microsoft operates datacenters in Bexar and Medina counties in the Greater San Antonio area. Microsoft says its local commitments include paying its way on electricity, minimizing and replenishing water use, creating jobs, adding to the local tax base, and investing in AI training and nonprofits. That does not disclose SAT82's exact IT load or subcontractors, but it confirms the regional data-center operating footprint around this permit.

Item	Source-backed detail	LVN read
Project	SAT82 Data Center	Microsoft-owned data-center building in the Greater San Antonio / Medina County cluster.
Location	18844 FM 1957, Castroville, TX 78009	Specific address for permit, inspection, utility, and local watch queries.
Scope	One-story building with five colos; about 244,676 sq ft	Data-hall, MEP, telecom-room, and commissioning work should be expected, but packages are not named.
Estimated cost	$482.6M TDLR estimated cost	Large enough to matter to mission-critical trade contractors.
Schedule	Start April 11, 2026; completion February 8, 2028	Current permit window puts civil, shell, MEP, low-voltage, controls, and commissioning signals in the 2026-2028 watch lane.

This packet is deliberately not treating every Castroville Microsoft filing as one project. The 18844 FM 1957 SAT82 record is separate from prior SAT80/SAT81 records at the same broader FM 1957 area, separate from SAT89/90 on US Highway 90 West, separate from SAT93/SAT94 on County Road 381, and separate from later SAT82 references at FM 471 North. Data Center Dynamics also noted that multiple SAT82 filings appear in Castroville and that it was unclear whether the later filing replaces or adds to the earlier one. LVN should keep this row pinned to TABS2024023976 until primary records say otherwise.

The design-firm role is one of the few named project roles that is source-backed today. TDLR names WSP USA Inc. as the design firm for TABS2024023976. WSP's own data-center services page lists capabilities that map directly to the systems LVN cares about: mechanical, electrical, plumbing and fuel oil, fire and life safety, building controls and monitoring, security, information and communication technology, analytics, power studies, and BIM. That does not mean WSP holds every discipline on SAT82, but it supports WSP as the design-firm / mission-critical engineering context.

Company / source	Role	Evidence
Microsoft Corporation	Owner / operator context	TDLR owner record and Microsoft Local regional page
WSP USA Inc.	Design firm	TDLR design-firm record
Microsoft Local	Regional owner/operator context	Greater San Antonio datacenters page
Baxtel	Secondary project profile context	SAT82 profile
Data Center Map	Secondary regional profile context	San Antonio SAT81 / SAT82 profile

The conservative contractor stance is simple: reviewed sources do not name the general contractor, EPCM, electrical contractor, low-voltage contractor, fiber/OSP contractor, structured cabling contractor, security integrator, fire alarm contractor, BAS/BMS controls firm, DAS/networking firm, grounding contractor, utility package holder, or commissioning agent for this TDLR record. Microsoft and WSP are source-backed. The rest should stay unknown until public records, plan-room notices, job postings, or owner/contractor pages name them.

The Microsoft Texas fact sheet reinforces the broader local context: Microsoft says it is operating and building facilities in Bexar and Medina counties and frames its approach around electricity-cost responsibility, water, jobs, tax-base support, and community investment. For LVN, those points translate into practical watch items: utility interconnection, substation and service work, water and cooling commitments, construction workforce, permanent operations jobs, and local training lanes.

System	Why it matters	Watch signal
Fiber / OSP	Five-colo data-center layouts need diverse entrance pathways, carrier handoffs, MMR/IDF support, and tested fiber.	Conduit, duct bank, vault, handhole, carrier, splicing, OTDR, and entrance-facility language.
Structured cabling	Data halls, admin/support areas, and network rooms require disciplined pathways, labeling, and test documentation.	Cable tray, rack/row, copper/fiber certification, labeling, and closeout requirements.
Access control / CCTV	Microsoft campuses require layered site, building, and secure-area controls.	Gate, badging, visitor, camera, VMS, analytics, perimeter, and equipment-yard security packages.
Fire alarm	Data-center buildings require life-safety coordination with equipment yards, suppression, monitoring, and AHJ acceptance.	Fire alarm permits, submittals, inspections, acceptance tests, and monitoring scope.
BAS/BMS / EPMS	Cooling, power, alarms, and facility systems need controls integration and turnover documentation.	Controls integrator, EPMS/BMS, point lists, trend logs, alarms, and commissioning records.
Grounding / commissioning	High-density facilities need bonding discipline, QA/QC, prefunctional checks, and turnover packages.	Grounding specs, commissioning agent notices, test reports, redlines, and final documentation.

The jobs and skills angle should stay practical. TDLR does not list construction headcount, and Microsoft did not disclose SAT82-specific craft counts in the reviewed records. That means LVN should avoid invented job numbers. The useful trade takeaway is preparation: OSHA and site onboarding, lift access, electrical-room coordination, fiber cleaning and inspection, OTDR and power-meter testing, copper certification, pathway and cable tray discipline, grounding and bonding, access-control commissioning, CCTV/VMS setup, fire alarm acceptance testing, BAS/BMS point verification, redlines, and turnover packages.

Secondary project profiles help with alias control but should not outrank the primary filing. Baxtel profiles Microsoft SAT82 near the San Antonio cluster, while Data Center Map places SAT82 in the same broader Microsoft Castroville footprint around SAT80/SAT81. Those are useful for nearby-site awareness. The TDLR record remains the binding source for this row's address, scope, owner, design firm, cost, and schedule.

The capacity stance also needs discipline. The reviewed public records support a 244,676-square-foot building and a $482.6 million TDLR estimated cost. They do not disclose MW, critical IT load, utility provider, generator count, water demand, tenant, GC, electrical contractor, or low-voltage package awards for this specific TABS2024023976 row. LVN should publish the confirmed building and cost facts, then leave the missing values as watch items.

The follow-up lane is clear: monitor TDLR/TABS for status changes, inspection movement, amended filings, and related SAT82 updates; watch Medina County, Castroville, San Antonio regional permitting, utility and interconnection records, Microsoft Local updates, WSP, plan-room channels, and job postings for GC/EPCM, electrical, low-voltage, security, fire alarm, controls, networking, grounding, and commissioning package names. Track aliases SAT82, SAT 82, Microsoft SAT82, 18844 FM 1957, FM 1957 data center, Castroville data center, Medina County Microsoft data center, and Greater San Antonio Microsoft datacenter.

Bottom line: Microsoft SAT82 at 18844 FM 1957 belongs in LVN Signal because it is a large, mappable, source-backed, active-construction-window data-center project with Microsoft as owner and WSP as design firm. The specialty contractor fields remain open. That is exactly the point of tracking it now: the public record is strong enough to publish, but early enough that low-voltage package holders may still surface through permits, hiring, plan rooms, or local construction updates.