WaterVerge

Is Cascade, ID Tap Water Safe to Drink?

Graded B+ — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

1K residents served 1 water system PWSID: ID4430012
Overall Score
82.6 / 100
Violations
5 active
Last Updated
May 2026
Source
Groundwater
#50 of 139 in Idaho Top 44% nationally
Local Government
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B+GRADE
Water Quality Grade
82.6/100
waterverge.com
B+ 82.6/100

Cascade, ID — Water Quality Report

Cascade's drinking water received a grade of B+ (82.6 out of 100), indicating good water quality. The city's 1 water system serves approximately 1,000 residents using groundwater.

Lead levels were measured at 6.0 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program.

The system has 20 violations on record, including 5 health-based violations. 5 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Cascade's water

Cascade ranks #50 out of 139 cities in Idaho for water quality, placing it mid-range in the state.

Cascade relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.

As a small community water system, Cascade may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
82.6 out of 100 Grade B+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
41.6/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
14/20
C
Lead at 6.0 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Cascade, ID water safe to drink?

Concerns Identified

Cascade's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (82.6/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 1,000 residents using groundwater (wells).

5
Active Violations
6.0 ppb
Lead (90th %ile)
3 events
Disaster History

Recent water quality updates for Cascade

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Cascade's water quality assessment. Grade: B+ (82.6/100).

Violation
1 drinking water violation recorded

Contaminants: Chlorine.

Violation
1 drinking water violation recorded

Contaminants: Groundwater Rule.

Disaster
SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES

Federal disaster declaration (FEMA DR-4443). Flood event — may have impacted local water infrastructure.

Disaster
SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES

Federal disaster declaration (FEMA DR-4313). Flood event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

Contaminants: Groundwater Rule.

Key contaminant findings

Based on the most recent EPA sampling data for Cascade's water supply.

Lead Elevated
Detected: 6.0 ppb Limit: 15 ppb (EPA Action Level)

Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.

Copper Exceeds Limit
Detected: 1.56 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

Violation history

Cascade's water system has 20 total violations on record, including 5 health-based violations. 5 remain unresolved. 2 violations were issued in the last 5 years.

MROtherTTMCL
Most recent violations:
Oct 2022 Chlorine Resolved
May 2021 Groundwater Rule Open
Jul 2016 Groundwater Rule Open
Jul 2015 Chlorine Resolved
Mar 2011 Groundwater Rule Open

Flood & environmental risk

Valley County has experienced 3 federally declared disasters since 2005. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Nf Payette River.

SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-4443
SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-4313
HURRICANE KATRINA
Hurricane FEMA DR-3244

Where does Cascade's water come from?

Cascade's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,000 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Nf Payette River (river).

What Cascade residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Cascade's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Flush your taps

Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.

Monitor alerts during storms

Cascade's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
6.0 ppb
EPA Action Level: 15 ppb · 40% of limit
Safe Level
Copper (90th percentile)
Inorganic
Over Limit
1.56 mg/L
EPA Action Level: 1.3 mg/L · +20% over limit
Exceeds Limit
Compliance Record

Violation summary

20
Total violations
5
Health-based
5
Active / unresolved
Oct 2022
Most recent violation
Compliance Record

Violations & advisories

20 Total
5 Active
5 Health-based
15 Resolved
Violations by category
Synthetic Organic Chemicals
5
Ground Water Rule
4
Total Coliform Rule
3
Stage 1 Disinfectants and Disinfection Byproducts Rule
2
Nitrate Rule
2
May 2021 Active
Groundwater Rule
Other Violation 0
Jul 2016 Active
Groundwater Rule
Other Violation 0
Mar 2011 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Mar 2011 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Active
Compliance Violation
Monitoring 0
Oct 2022 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jul 2015 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2015
Jan 2011 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2011
Jan 2009 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2009
Nov 2006 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Nov 2006
Aug 2005 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 2005
Jan 1999 Resolved
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 1999
Jul 1998 Resolved
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 1999
Jan 1996 Resolved
Dalapon
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2001
Jan 1996 Resolved
Dinoseb
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2001
Jan 1996 Resolved
Picloram
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2001
Jan 1996 Resolved
2,4,5-TP
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2001
Jan 1996 Resolved
2,4-D
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2001
Aug 1995 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 1995
Jan 1992 Resolved
Surface Water Treatment Rule
Treatment Technique
Health-Based Health Resolved Dec 1997
Environmental Risk

Drought conditions

D2 — severe drought

Valley County is currently in D2 (severe drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

6
Weeks at D2+ (current streak)
30.9%
Months in D2+ (last 30y)
6
Weeks at D2+ (last 5y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

3
Declared disasters
Jun 2019
Most recent
Flood
Most common type

Valley County has experienced 3 federally declared disasters since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Jun 2019
SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #4443
May 2017
SEVERE STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #4313
Sep 2005
HURRICANE KATRINA
Hurricane FEMA #3244

Recommended water filters

Based on contaminants detected in Cascade's water supply, we recommend the following filter types.

🚰
For Lead
Reverse Osmosis or NSF 53-Certified Pitcher
Lead detected at 6.0 ppb
Read our guide →
🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 6.0 15 ppb Inorganic Safe
Copper (90th percentile) 1.56 1.3 mg/L Inorganic Over Limit
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 19.0 ppb from 1993 (25.0 ppb) to 2024 (6.0 ppb).

Copper level (90th percentile)

Latest reading: 1.560 mg/L (1993)

EPA action level: 1.3 mg/L

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
1,000
Water Systems
1
Water Source

Where Cascade's water comes from

Groundwater

Cascade's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by local government ownership and serves approximately 1,000 people through 1 water system.

Local Hydrology

Water bodies near Cascade

Cascade is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Nf Payette River
river
Infrastructure

Water systems serving Cascade

System Name PWSID Population Source
CASCADE CITY OF ID4430012 1,000 GW
Regional Comparison

How Cascade compares

Full Idaho rankings →

Cascade's score of 82.6/100 is above the average of 43/100 among major Idaho cities. It outscores 10 of 10 nearby cities.

Cascade (this city)
82.6
Boise
33.6
Meridian
42.9
Nampa
41.8
Caldwell
38.5
Idaho avg
43
City Profile

About Cascade, ID

Wikipedia →

Cascade is a rural city in and the county seat of Valley County, Idaho, United States. The population was 1,005 at the 2020 census.

Economic Profile
$48,700
Median Income
$305,275
Median Home Value
$1,010/mo
Median Rent
4.7%
Unemployment
Community
53.4
Median Age
112
People / sq mi
27.9%
College Educated
87.2%
Homeownership
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Frequently asked questions

Is Cascade, ID tap water safe to drink?

Cascade's water quality earned a grade of B+ (82.6/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #50 out of 139 cities tested in Idaho.

What contaminants are in Cascade's water?

Lead was measured at 6.0 ppb (90th percentile). 20 violations are on record.

How is Cascade's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Cascade?

While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.

Where does Cascade's water come from?

Cascade's water is sourced from Groundwater. The city has 1 water system serving approximately 1,000 residents.

What health violations has Cascade's water system had?

Cascade has 5 health-based violations on record. The most recent violation was recorded in October 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 5 violations remain unresolved.

Is Cascade's groundwater at risk of contamination?

Cascade uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 20 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does Cascade's water compare to other cities?

Cascade ranks #50 out of 139 cities in Idaho (better than 64% of state cities) and #6885 out of 15744 cities nationally (56th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Cascade's small water system affect quality?

Cascade's system serves approximately 1,000 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 20 violations on record.