Highlights A Study of Phosphorus Loading of Ballston Lake by Tributary Inflow Presentation to BLIA Annual Meeting June 16, 2014 Scott Miller, Bob Duncan, Dave Pierce 1

Over Last 10 Years Average Phosphorous Levels Increased from 25 to 40 P.P.B 2

Three suspected sources: 1.Reintroduction of natural sources through lake level changes and lake ecology changes 2.Septic and fertilizer from shoreline residential development 3.Inflow from the watershed. This Study 3

Three different tributaries were sampled. Heavily Developed Slated for Future Development Relatively Undeveloped 4

7 Storms Were Sampled 5

Example: Pounds of Total P Contribution from one creek in one storm Flow Measurements to calculate volume of storm 1.95 MM Cubic Feet x 82 PPB = 10 Pounds of TP 6

Buell Heights P was 4 to 6 times more concentrated and contributed more Total P than other two creeks Pounds of Total P by Storm 7 EPA Criteria for creeks into lakes in our region 700 Ranges of Total P by Storm

Weekly Lake Samples Show Seasonality of P Measurements Total P increased while rainfall decreased. Total P measurements correlate with lake temperature 8

Temperature Impact via Dissolved Oxygen may cause the Summer Increase of P Anoxic conditions at low levels mobilize soluble P. Soluble P convects to surface as the summer temperatures rise. 9

Conclusions Phosphorus enters the lake from creeks 3 times ( PPB) more concentrated than it leaves the lake (40 PPB). Buell Heights Creek has a mean concentration of 140 PPB with spikes up to 250 (vs. EPA guidelines of 35 to 40 for creeks). Buell Heights Creek contribute 4 to 6 times more phosphorus per acre of watershed than the rural tributaries. There is a seasonal component for lake P observations, that correlate with temperature. 10

Recommendations In 2012, NYS DEC listed B.L. as an impaired water requiring a remediation plan. Enhance practices to reduce flow, such as wooded stream buffers, storm retention basins, and artificial wetlands. – Consider sedimentation basins for Sweet & Buell Heights. – Roadside ditch cleanouts should be immediately seeded. Encourage the development of a municipal sewer system in B.L. watershed Further Study – Measure Lake P to verify seasonality. – Study D.O. profiles to verify biological transport. In Process. – Measure contribution of P by lake residents. – Measure tributary temperatures to determine temperature stratification, impacting measurements. – Bacteria tests for Buell Heights. – Follow up stream tests in 5 years to measure changes and impact from banned phosphorus in lawn fertilizer. 11