Escuela de Walker.
A bilingual K-8 charter school at 312 W. Bruce Street in Walker's Point, on the books since 2017. Five assemblies on a 1903 Cream-City brick building one block from our shop. A chemistry classroom that became a high-hazard finding in 2019 and re-shaped the entire site's protection.
The building
312 W. Bruce Street is a three-story Cream-City brick building completed in 1903 as a German-language parish school for the now-deconsecrated St. Patrick of Walker's Point. The building shifted to public-school use in the 1950s, was vacant from the 1990s through 2014, and was renovated into a bilingual charter (K-8) in 2014–2016. The 4″ combination fire-and-domestic water service was installed in the 2016 renovation by Hunzinger Construction's mechanical contractor; we inherited the cross-connection protection account in March 2017 after the school's first annual notice from MWW.
The building is on the National Register as a contributing structure to the Walker's Point Historic District. Original interior elements include the pressed-tin ceilings on the second-floor classroom wing, the cast-iron radiator network on the third floor, and a clay-tile chimney that vented coal-fired heating until 1968. The mechanical room — where four of the five assemblies live — is in the basement, accessed through the original coal-chute opening on the east elevation.
Initial survey (2017)
The initial cross-connection survey took eight hours over two days. We found:
- 4″ RPDA at the combined service entrance (Wilkins 350ADA)
Installed in 2016. Compliant for high-hazard fire service.
- 1″ DC isolating the boiler glycol loop (Watts 919)
Non-compliant. Boiler was dosed with propylene glycol at 30%. Required upgrade to RP.
- 3/4″ PVB on the irrigation lateral (Febco 765, exterior southeast wall)
Compliant for no-injection irrigation. Note: no fertigation pump on site.
- Cafeteria three-comp sink with hose-end sprayer below flood-rim
No isolation in place. SVB on the spray-arm supply required.
- Janitor closet on each floor: hand-faucet with hose attachment
No isolation. SVB required on each.
The 2017 work order — survey + four installs (one RP upgrade, three SVBs on janitor closets, one SVB on the cafeteria spray-arm) — closed in May 2017. Total: $4,840.
The 2019 finding
In May 2019 we tested the assemblies as scheduled and during the walk discovered that the school had added a working chemistry classroom on the third floor over the winter break. The classroom had two faucets, one with an aspirator (for filtration experiments), and a fume hood with a small lab sink. None of those fixtures had cross-connection protection. The aspirator alone was a textbook high-hazard back-siphonage path — under low supply pressure it could pull beaker contents back through the faucet into the building's potable line.
We added a finding to the test report: "Newly-installed lab faucets and aspirator on 3F chem classroom (rm 314) require ASSE 1056 SVB protection plus an air-gap on the beaker rinse. Estimated cost: $1,160. Re-test within 30 days." The school authorized the work within a week. We installed two Watts 008 SVBs on the lab faucets and installed an engineered air-gap on the rinse basin. The chem classroom passed re-test on June 14, 2019.
The same survey also raised the protection class on the 1″ RP that isolated the boiler glycol loop, which had been upgraded from DC to RP in 2017 but was now near the end of its diaphragm cycle. Rebuild kit installed during the May 2019 visit; no replacement needed.
Current protection (2026)
| # | Location | Assembly | Hazard | Last test | Next due |
|---|---|---|---|---|---|
| 1.1 | Basement, service entrance | Wilkins 350ADA · 4″ RPDA · ZW-77104 | High | 2026-05-14 · Pass | 2027-05 |
| 1.2 | Basement, boiler glycol loop | Watts 909 · 1″ RP · WT-441100 | High | 2026-05-14 · Pass | 2027-05 |
| 1.3 | 3F chem classroom, lab faucet A | Watts 008 · 1/2″ SVB · WT-008-12440 | High back-siph | 2026-05-14 · Pass | 2027-05 |
| 1.4 | 3F chem classroom, lab faucet B | Watts 008 · 1/2″ SVB · WT-008-12441 | High back-siph | 2026-05-14 · Pass | 2027-05 |
| 1.5 | Exterior southeast, irrigation | Febco 765 · 3/4″ PVB · FB-998111 | Mod | 2026-04-30 · Pass | 2027-04 |
| 1.6 | Cafeteria, three-comp sink spray-arm | Watts 008 · 1/2″ SVB | Mod | 2026-05-14 · Pass | 2027-05 |
| 1.7 | Janitor closets (×3, one per floor) | 3× Febco 765SR · 1/2″ SVB | Mod | 2026-05-14 · all Pass | 2027-05 |
Annual rhythm
The school is on an in-service-day schedule — testing happens on the day before Memorial Day, when students are off but staff is on-site. Ferraro is the testing tester since 2017. The test report goes to the school's facility manager and to MWW the same afternoon. Total visit duration in 2026: 3 hours 40 minutes for nine assemblies. Total invoice: $1,920 (annual cycle at standard rates, less the multi-assembly discount).
References
- National Register of Historic Places — Walker's Point Historic District. en.wikipedia.org
- Encyclopedia of Milwaukee — Walker's Point. emke.uwm.edu
- USC FCCCHR Manual §3.4 — Hazard classification. usc.edu/dept/fccchr
- Wisconsin DPI Charter Schools Office. dpi.wi.gov
- MWW §295-1. water.milwaukee.gov
- Hunzinger Construction. hunzinger.com