Lake Johnson
- +Higher grade (F → D)
- +Lower phosphorus (40 vs 50 µg/L)

2 lakes with lower nutrient and algae readings within 30 miles, ranked by grade improvement and proximity.
Bass Lake carries nutrient and algae readings on record. Within 30 miles, 2 lakes read lower. Lake Johnson (Wake County, Grade D, 9.8 mi away) is the closest meaningful upgrade.
Within 30 miles of Bass Lake, 2 lakes carry lower nutrient and algae readings on the EPA water-quality metrics. The short list means the alternatives are real upgrades but not interchangeable: each carries its own access, size, and species mix worth checking before substituting it into a weekend plan.
Lake Johnson (Wake County) is the closest cleaner option at 9.8 miles from Bass Lake: close enough to be a genuine substitute for most users, far enough that it isn't the same neighborhood lake. Worth the trip if water quality is the primary driver; less obvious if Bass Lake is on the way to other plans.
Each lake's nutrient and algae readings — total phosphorus, total nitrogen, chlorophyll-a, and turbidity — are shown beside the EPA National Lakes Assessment 2022 condition class for that lake's own ecoregion, so a reading is compared against the lakes it would naturally resemble. LakeQuality publishes no letter grade. Lower readings mean measurably less nutrient and algae in the water, not better scenery or access: the lake with the clearest, lowest-nutrient water can have worse boat-launch facilities or shoreline access than a neighbor, so the comparison is one input alongside the rest of trip planning. How the readings are classified is on our methodology page.
Sampled lakes on LakeQuality carry readings from EPA Water Quality Portal samples — nutrients and algae measured against EPA National Lakes Assessment ecoregion classes. Secchi is shown, not scored. To suggest cleaner alternatives, we filter lakes within 30 miles to those with a strictly higher numeric score, then rank by the size of the improvement with a small proximity tiebreak. Cross-state and limited-data lakes are excluded so the list stays locally relevant.