Water utilities in Boise have maintained a consistent compliance record over recent monitoring periods - the city's above-average grade in ID reflects low violation rates and no systemic health concerns flagged in current data.

Data: EPA SDWIS, FEMA NFIP, Census ACS Last verified: 2026-07-19

Water Quality in Boise

We track water quality and home safety data for 32 ZIP codes in Boise, Idaho (population ~265,704), covering 8 community water systems serving approximately 441,256 people region-wide.

32 of 32 ZIP codes (100%) have recorded EPA violations - 544 total, including 96 health-based violations.

Average Home Safety Score: B (71/100)

Water sources: Groundwater, Surface water.

Top Contaminants

Lead Risk

• Average lead level (90th percentile): 0.0020 mg/L
• 50% of housing built before 1986 (when lead solder was banned)
• 11% of housing built before 1950 (when lead pipes were standard)
• Median year built: 1983
• Most common estimated pipe material: Copper
• Lead exposure risk score: 41/100
• Estimated lead service line probability: 14%
• 4 ZIP codes classified as high or very high lead risk

With 50% of homes built before the 1986 lead solder ban, Boise residents - especially those in older neighborhoods - should consider testing their tap water for lead. Homes built before 1950 are at the highest risk of having lead service lines.

Housing Age Distribution

113,845 total housing units across 32 ZIP codes:

Flood Risk

FEMA National Flood Insurance Program data for Boise:

• 72 flood insurance claims on record
• $164,170 total paid out
• $2,280 average claim payout
• Dominant FEMA flood zone: X (Low risk)
• 2 of 32 ZIP codes in high-risk flood zones (A/V)

Radon Risk

Dominant EPA radon zone: Zone 2 (Moderate Risk)

• Zone 1 (High): 1 ZIP codes
• Zone 2 (Moderate): 31 ZIP codes
• Zone 3 (Low): 0 ZIP codes

The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.

Neighborhoods by Safety Score

Safest Areas

Areas Needing Attention

What Boise Residents Can Do

Test Your Water

• Order a certified lab test - home test kits cost $20–50 and cover lead, bacteria, and common contaminants
• Request your utility's CCR (Consumer Confidence Report) - your water provider must publish this annually
• Check your ZIP code - each area in Boise has different water systems and risk levels

Filter Your Water

• NSF-certified pitcher filter removes chlorine taste and some contaminants ($20–40)
• NSF 53-certified filter for lead - recommended for homes built before 1986
• Reverse osmosis system removes 95%+ of contaminants including lead, PFAS, and nitrates ($150–400)

Test for Radon

• Boise is in a moderate-risk radon area
• Short-term radon test kits cost $10–25
• If levels exceed 4 pCi/L, EPA recommends professional mitigation

Stay Informed

• Visit your ZIP code report for detailed, address-level data
• Sign up for EPA water quality alerts
• Review the annual water quality report from your local utility

All ZIP Codes in Boise

• 83701 [B] - 17 violations ⚠
• 83702 [C] - 17 violations ⚠
• 83703 [B] - 17 violations ⚠
• 83704 [B] - 17 violations ⚠
• 83705 [B] - 17 violations ⚠
• 83706 [C] - 17 violations ⚠
• 83707 [B] - 17 violations ⚠
• 83708 [B] - 17 violations ⚠
• 83709 [B] - 17 violations ⚠
• 83711 [B] - 17 violations ⚠
• 83712 [B] - 17 violations ⚠
• 83713 [B] - 17 violations ⚠
• 83715 [B] - 17 violations ⚠
• 83716 [C] - 17 violations ⚠
• 83717 [B] - 17 violations ⚠
• 83719 [B] - 17 violations ⚠
• 83720 [B] - 17 violations ⚠
• 83721 [B] - 17 violations ⚠
• 83722 [B] - 17 violations ⚠
• 83724 [B] - 17 violations ⚠
• 83725 [B] - 17 violations ⚠
• 83726 [B] - 17 violations ⚠
• 83727 [B] - 17 violations ⚠
• 83728 [B] - 17 violations ⚠
• 83729 [B] - 17 violations ⚠
• 83730 [B] - 17 violations ⚠
• 83731 [B] - 17 violations ⚠
• 83732 [B] - 17 violations ⚠
• 83735 [B] - 17 violations ⚠
• 83756 [B] - 17 violations ⚠
• 83757 [B] - 17 violations ⚠
• 83799 [B] - 17 violations ⚠

Frequently Asked Questions

Is the tap water safe to drink in Boise, ID?

Boise has an average Home Safety Score of 71/100 (grade B) across 32 ZIP codes. There are 544 recorded EPA violations, 96 of which are health-based. Safety varies by neighborhood - check your specific ZIP code report for details.

Does Boise have lead in the water?

The average 90th-percentile lead level across Boise is 0.0020 mg/L, below the EPA action level of 0.015 mg/L. No ZIP codes currently exceed the EPA lead action level. About 50% of housing was built before 1986, when lead solder was banned.

Is Boise at risk for flooding?

FEMA data shows 72 flood insurance claims in Boise ZIP codes, with an average payout of $2,280. 2 of 32 ZIP codes are in high-risk FEMA flood zones (A or V).

Are there lead pipes in Boise homes?

50% of Boise housing was built before 1986, when lead solder was common in plumbing. 11% was built before 1950, when lead pipes were standard. The most common estimated pipe material is Copper. The estimated probability of lead service lines is 14%. We recommend testing your water if your home was built before 1986.

What contaminants have been found in Boise water?

The most common contaminants by violation count are Combined Radium, Stage 1 DBP Rule, Stage 2 DBP Rule. Across 32 ZIP codes, 32 have recorded EPA violations. Check your ZIP code report for the specific contaminants in your area.

Data Sources

• Water quality: EPA Safe Drinking Water Information System (SDWIS)
• Lead/copper: EPA Lead and Copper Rule sampling data
• Housing age: U.S. Census Bureau American Community Survey
• Flood data: FEMA National Flood Insurance Program
• Lead exposure: Composite risk score based on housing age, water lead levels, and service line estimates
• Radon: EPA Map of Radon Zones

Updated daily.

Housing Age Profile

Housing age matters for water quality because lead solder was widely used in plumbing until the 1986 federal ban. Boise's median build year of 1983 suggests a majority of homes were constructed under the newer standard - a meaningful factor when assessing household-level lead risk from tap water.

1983

Median Year Built

0%

Pre-1986 (Lead Paint Risk)

0%

Pre-1970 (Lead Pipes Risk)

Most homes in Boise were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.

Source: U.S. Census Bureau ACS B25034.

Protecting Children from Lead in Boise

0.002

mg/L Avg Lead (Limit: 0.015)

Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.

Lead risk in Boise appears low overall, but individual homes may differ. Testing is the only way to confirm your water's lead content.

Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.

Climate-Related Water Risk for Boise

FEMA-designated flood zones cover a small share of Boise's ZIP codes, and NFIP claim volume reflects that limited exposure. Flood-related water quality disruptions - overwhelmed treatment capacity, well contamination, backflow - are infrequent where flood events themselves are rare.

72

Total FEMA Flood Claims

~4

Est. Claims/Year

Boise has a relatively low flood history with 72 FEMA claims on record. While risk is limited, severe weather events can still impact water infrastructure.

How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure.

Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.