Data: EPA ECHO, Census ACS, NTSB Last verified: 2026-05-03

What is infrastructure decay probability?

Infrastructure decay probability estimates the likelihood of water pipe deterioration based on pipe age, material type, violation history, and environmental conditions. Higher probability means greater risk of water main breaks, pressure drops, and contamination from aging pipes. The national average hovers around 30-40%. Norwalk's average is 31%.

Infrastructure Risk Distribution

How Norwalk's {totalZips} ZIP codes are distributed by infrastructure risk level:

Low 0 ZIPs

Moderate 1 ZIP

High 0 ZIPs

Very High 0 ZIPs

Infrastructure Risk Overview

Norwalk, Iowa has moderate infrastructure risk with an average decay probability of 31%. Some portions of the water system may require attention as infrastructure ages.

Infrastructure decay probability measures the likelihood of pipe failure, water main breaks, and system degradation based on pipe age, material, violation history, and environmental factors.

Key Infrastructure Metrics

Metric	Value
Decay probability	31%
Risk level	moderate
Water systems	2
Median build year	1992
Pre-1986 housing	36%
CO/gas incidents	0
ZIP codes	1
Population	14,550

Infrastructure Risk Distribution

How Norwalk's 1 ZIP codes are distributed by infrastructure risk level:

Water System Age and Pipe Materials

The median home in Norwalk was built in 1992 (approximately 34 years old). Housing age is one of the strongest proxies for water infrastructure age, as service lines and interior plumbing were typically installed during construction.

Pipe material risks by era:

Carbon Monoxide & Gas Safety

No CO/gas incidents have been recorded in the county covering Norwalk. The average CO risk score is 0 out of 100.

Carbon monoxide is odorless and colorless — it is the leading cause of poisoning deaths in the U.S. Risk factors include:

• Gas furnaces, water heaters, and stoves
• Attached garages
• Blocked chimneys or vents
• Portable generators used indoors

Prevention:

• Install CO detectors on every level, especially near bedrooms
• Have gas appliances inspected annually
• Never run generators, grills, or cars in enclosed spaces
• Replace CO detectors every 5-7 years

What Homeowners Can Do

Pipe Inspection

• Hire a licensed plumber to inspect your service line and interior plumbing
• Check for discolored water (brown/orange = rust; white/cloudy = air or sediment)
• Test water pressure — low pressure may indicate buildup in aging pipes
• Look for visible corrosion on exposed pipes in basement or utility areas

Water Heater Maintenance

• Flush your water heater annually to remove sediment
• Check the anode rod every 2-3 years (prevents tank corrosion)
• Set temperature to 120F to prevent scalding and reduce energy use
• Replace water heaters older than 10-15 years proactively

CO Detector Placement

• One detector per floor, minimum
• Within 10 feet of each bedroom door
• Near attached garage and utility room
• 5 feet above the floor (CO rises with warm air) or on the ceiling
• Not near windows, doors, or HVAC vents (air movement causes false readings)

Norwalk vs. Nearby Iowa Cities

How Norwalk's infrastructure compares to nearby cities:

ZIP Codes in Norwalk

Norwalk covers 1 ZIP code served by 2 water systems. Infrastructure condition varies by ZIP code based on housing age, pipe material, and water system maintenance. Check your specific ZIP code for localized data.

Data Sources

• Water systems: EPA ECHO — Enforcement and Compliance History Online
• Infrastructure risk: Derived model (housing age, violation history, system assessments)
• Housing age: U.S. Census Bureau American Community Survey (ACS)
• CO/gas incidents: NTSB, PHMSA pipeline incident reports

Updated daily.

Infrastructure Risk by ZIP Code in Norwalk

Infrastructure risk varies across Norwalk's 1 ZIP codes based on system age, pipe materials, and violation history.

ZIP Code	Grade	Score	Violations
50211	C	63/100	0	View report →