Togus Pond Development Surveys Lauren Wolpin. Development Overview Shoreland Zoning Regulations...
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Transcript of Togus Pond Development Surveys Lauren Wolpin. Development Overview Shoreland Zoning Regulations...
Togus Pond Development Surveys
Lauren Wolpin
Development Overview
• Shoreland Zoning Regulations
• Wastewater Disposal
• Development Survey
• Buffer Strip Survey
• Roads
• Future Development
Mandatory Shoreland Zoning Act
• Rural Ponds District
• Municipal Ordinances– Setback– Shore frontage– Lot size– Area of impervious
surface
• Non-conformance
Togus Pond Septic Systems
• Shoreland challenges– Water table– Shoreline erosion– Winterization of
camps– Grandfathered
systems
Togus Pond Septic Systems
• Remediation– Water conservation– Regular pumping– Landscape improvements– New construction
Development Survey
Location
Nu
mb
er o
f H
ouse
s
Buffer Strips
Well-buffered home• Almost full lakeshore coverage
• Mix of trees and shrubs• Rip rap• Could be better
Poorly-buffered home• House very close to water• Exposed soil• No shrubs, few trees• Rip rap incomplete
Togus Pond Buffer Strips
Inadequate buffer strips are a problem
Buffer Rating• Fail
• Poor
• Fair
• Good
Camp Roads
• Soil erosion is a major contributor of phosphorus
• Proximity to lake is a concern
Well-maintained culvert Poorly-maintained culvert
Maintenance Matters!
Berms prevent water from leaving the roadbed
Erosion on Ingraham Mountain Road
Road Survey Results
• Poor roads in Northwest corner
• Most roads acceptable or good
• Culverts most common problem
Steep Driveways
• Identified problem driveways
• Many lead straight into the lake
• Steep slopes lead to erosion
• Tasker Road, Hayes Road, Albee Road
Future Development
• Land clearing on Young Road
• Commercial areas
• Golf course
• Pipeline and Gerabro Acre Roads
Phosphorus Budget
Kara Lanahan
• Background and history
• Current nutrient status
• Phosphorus budget
Phosphorus Overview
• Cultural eutrophication
• Secchi disk transparency < 2 m
• Phosphorus concentration > 15 ppb
Phosphorus Background
Historical Phosphorus
1976
1977
1978
1979
1980
1981
1987
1988
1989
1990
1991
1999
0 10 20 30 40 50 60 70 80 90 100Total Phosphorus (ppb)
Summer
Fall
QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.
Phosphorus: Results
• Mean phosphorus: 28 ppb
• Trophic State Index (TSI): 67– East Pond TSI = 64– Great Pond TSI = 39
Summer Phosphorus Levels
9-Jun-2004
23-Jun-2004
7-Jul-2004
21-Jul-2004
3-Aug-2004
16-Aug-2004
20-Sep-2004
0 5 10 15 20 25 30 35Total phosphorus (ppb)
0
50
100
150
200
250
300
350
400
450
Surface Mid-depth Bottom
Figure 26. Distribution of total phosphorus at Site 1 by depth. Site 1 has adepth of 14.7 m. See Togus Pond Site map for location of Site 1 (Figure 11).
401 ppb
• What is it?
• How is it calculated?
• What does it mean in terms of lake health?
Phosphorus Budget
QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.
Togus flushing rate = 0.81
Diagram of a phosphorus budget
W = external P load + internal P load
W is the annual P load (kg/yr)
Calculating the budget
Components of the phosphorus budget
• Watershed land use
– Coefficient
– Land area
• Septic systems
– Soil retention
– Occupancy rates
• Internal recycling and sediment release– Anoxia
– Water quality
Sediment Release
Phosphorus Model Results
Total Phosphorus load
• Best 794 kg P/ year
• High 1169 kg P/year
• Low 392 kg P/year
Total concentration
• Best 19 ppb
• High 28 ppb
• Low 9 ppb
Percent contribution of all land use types
12%
2%
25%
1%9%5%4%
1%
14%
3%
23%
1%
0.3%
Atmospheric InputMature forestOld FieldForestWetlandsCleared LandCommercialCamp RoadsRoadsHaylandShoreline DevelopmentNon-shoreline DevelopmentShoreline Septic SystemsNon-shoreline Septic Systems
• Total external load (direct watershed): 410 kg/yr
1. Forest: 107 kg/yr or 25-26% of total P load
2. Shoreline septic tanks: 96 kg/yr or 23%
3. Shoreline development: 56 kg/yr or 14%
• Sediment release contributed the most phosphorus: 328 kg/yr
Total Phosphorus Loading Results
P source Togus Pond Threemile Pond Webber Pond
1 Sediment
Release
Reverting land Sediment
Release
2 Forest Sediment
Release
Agriculture/
Golf course
3 Shoreline
septic tanks
Transitional
Forest
Threemile
Pond
What about phosphorus in other Central Maine lakes?
• Decrease inputs from watershed
• Decrease internal loading through remediation
What needs to change to improve lake health?
• Shoreline septic tanks
• Minimize shoreline development
Where will this reduction come from?
• Most of Togus Pond’s phosphorus comes from internal recycling and sediment release
• The external load must be reduced first
Phosphorus Model Conclusions
In Lake Remediation
Wendy Sicard
Nutrient Control Techniques Possible for Togus Pond
• Alum Treatment
• Water Drawdown
• Biomanipulation
• Vegetative Mats
Alum Treatment
• Aluminum sulfate
binds with P
• Effective for
internal P loading
Alum Treatment
• Can last <1 year to
20 years
• Costly: average $450
per acre
• Testing and
monitoring
Manipulation of Fish Stocks
• Lower algae by increasing algae- consuming zooplankton
• Reduce planktivorous fish or restock piscivorous fish
• Comparatively inexpensive
Water Drawdown
• Removal of
nutrient-rich water
• Modification of
culvert and dam
Vegetative Mats
• Absorb nutrients in
contained rafts
• Provide cover for
zooplankton
• Harvest and compost
Solutions for Togus Pond
• Stop inflow
• Funding
• Research of effects
• Multi-step approaches
Recommendations
Rob Mehlich
Recommendations overview
• Watershed management
• In-lake management
• Monitoring and regulations
• Community awareness and education
• Grants and funding
Watershed Management
• Buffer strips and erosion– Impervious surfaces– Coverage and depth– Rip rap
• Roads– Maintenance– Limited and monitored construction
Watershed Management
• Septic systems– Old systems– Pump outs– Upgrades
• Land use– Enforcement– Deforestation
In-Lake Management
• Implementation of applicable remediation techniques
• Continued watershed management
• Studies and monitoring of remediation
Monitoring and Regulations
• Maine Volunteer Lake Monitoring Program
• Worromontogus Lake Association
• Wetlands protection
Grants and Funding
• Maine Department of Environmental Protection– Nonpoint source water pollution control grants– Small community grant programs
• Maine Department of Transportation– Surface Water Quality Protection Program
Community Awareness
• Phosphorus free fertilizers
• Phosphorus free household detergents
Summary
Summary
• Eutrophication
• Phosphorus is entering the lake from soil runoff and human uses of the land and from sediment in the lake.
• This leads to algal blooms and a decrease in water quality.
Summary
• Phosphorus that comes from sources outside the lake should be reduced.– Buffer strips– Roads – Septic systems – Detergents, and fertilizers
• Remediation techniques may help reduce the phosphorus that is already stored in the lake sediments.– Alum treatment – Fish stock manipulation– Drawdown– Vegetative mats
Summary
AcknowledgementsWe would like to give our thanks to the people and organizations that generously provided their time, knowledge, and support.
Thank you.
Roy Bouchard, Maine Department of Environmental ProtectionRussell Cole, Colby CollegePaul Connolly, Togus Pond ResidentDennis Curtis, Togus Pond ResidentFred Dillon, Maine Association of Conservation DistrictsRichard Dolby, Director of Code EnforcementDavid Firmage, Colby CollegeRoger Gagnon, Togus Pond ResidentDavid Halliwell, Maine Department of Environmental Protection Rebecca Manthy, China Lakes AllianceJeff Norton, Elma’s Tackle and Hunting Supply StoreJohn Pucciarelli, President of the Worromontogus Pond AssociationGeorge Soucy, Code Enforcement OfficerNate Sylvester, Lakes Program, Kennebec County Soil and Water Conservation DistrictDan Tierney, Colby CollegeBill Woodward, Maine Department of Inland Fisheries and WildlifeBobby Van-Riper, Maine Department of Inland Fisheries and WildlifeAugusta Town OfficeMaine Department of Environmental ProtectionMaine Department of Inland Fisheries and Wildlife StaffMaine Soil and Water Conservation Staff
Questions