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LakeQuality

Ohio vs Indiana, Lake Water Quality Comparison

A data-driven comparison of lake water quality between Ohio and Indiana, built from EPA Water Quality Portal monitoring data.

OhioIndiana
Total Lakes1722
Average GradeDD
Average Score0.841.45
Grade A Lakes01
Grade B Lakes04
Grade C Lakes35
Grade D Lakes96
Grade F Lakes56
Oligotrophic (Cleanest)01
Eutrophic (High Nutrient)1512
Lakes with Invasives14
Improving Trend25
Declining Trend57

Analysis

Ohio has 17 graded lakes averaging a D (score 0.84), while Indiana has 22 graded lakes averaging a D (score 1.45). On average water quality, Indiana comes out ahead.Ohio counts 0 Grade A lakes and 0 oligotrophic (clearest-class) lakes, against 1 and 1 for Indiana.

Long-term monitoring shows 2 improving and 5 declining lakes in Ohio, versus 5 improving and 7 declining in Indiana. Dataset coverage varies by state: Ohio has maximum-depth data for 0 lakes and documented fish species on 0, compared with 0 and 0 for Indiana. Where a figure is zero, that state dataset has not yet been ingested — grades there rest on EPA clarity and nutrient measurements alone.

Frequently Asked Questions

Does Ohio or Indiana have cleaner lakes?

Ohio has an average lake grade of D (score 0.84) while Indiana averages D (score 1.45). Indiana has the better average water quality. Grades are computed from EPA Water Quality Portal clarity and nutrient measurements.

Which state has more graded lakes?

Ohio has 17 graded lakes while Indiana has 22. Counts reflect lakes with enough EPA Water Quality Portal monitoring data to grade, not the total number of lakes in each state.