Watershed Below TMDL Threshold At TMDL Threshold Above TMDL - - PowerPoint PPT Presentation

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Feb 22, 2024 433 likes •635 views

Nantucket Harbor Watershed Below TMDL Threshold At TMDL Threshold Above TMDL Threshold Water Quality Overview Routine monitoring: June-September. Water quality, dissolved oxygen, algae, eelgrass. Work with State agencies to

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Nantucket Harbor Watershed

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Above TMDL Threshold At TMDL Threshold Below TMDL Threshold

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Water Quality Overview

Goa

6 6 ye year ar Average 2017 2017

 Routine monitoring: June-September.  Water quality, dissolved oxygen, algae, eelgrass.  Work with State agencies to ensure healthy swimmable, fishable waters.

Low Nitrogen: High Nitrogen: Very High Nitrogen:

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Nantucket Harbor

0.000 0.050 0.100 0.150 0.200 0.250 0.300 0.350 0.400 0.450 0.500 Historic 2010 2012 2013 2014 2015 2016 2017 Total Nitrogen (mg/L) Head of Harbor Quaise Lower Harbor Ocean Threshold

2010-2017 are full summertime averages from MEP tech memo.

Dissolved Oxygen- Acceptable. Algae Biomass- Acceptable. Harmful Algae Presence- Pseudo -nitzschia elevated in March, July, August, September. Red tide species present. Rust tide present at low levels April, September; Wauwinet elevated in

August. Phaeocystis bloom in February-April.

August Scup Fishkill in Creeks. Sentinel

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Polpis Harbor

0.000 0.050 0.100 0.150 0.200 0.250 0.300 0.350 0.400 0.450 0.500 Historic 2010 2012 2013 2014 2015 2016 2017 Axis Title Average Ocean Threshold

2010-2017 are full summertime averages from MEP tech memo

Dissolved Oxygen- Acceptable. Algae Biomass- Elevated in August. Harmful Algae Presence- Red tide species in May, June, August. Rust tide elevated August. Sentinel

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Madaket & Hither Creek

0.1 0.2 0.3 0.4 0.5 0.6 0.7 Historic 2010 2012 2013 2014 2015 2016 2017 Axis Title Hither Creek Sentinel Harbor Average Eel Point Threshold

2010-2017 are full summertime averages from MEP tech memo.

Dissolved Oxygen- Harbor acceptable, Hither Creek periodic oxygen below healthy threshold. Algae Biomass- Harbor acceptable, Hither Creek- June, July, August above healthy threshold. Harmful Algae Presence- Red tide species elevated in August. Sentinel

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NLC and DPW Stormwater Sampli ling Program

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St Stormwater Capital Im Improvements Best Management Practices (BMP’s)

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TON/DPW Stormwater Im Improvement Strategy

Stormwater drainage and outfall mapping
Monitoring and maintenance plan for stormwater

drainage elements

Stormwater capital improvements (BMP’s)
Develop enforceable stormwater policies (regulate illicit discharge, construction

site management, post-construction stormwater control)

Stormwater pipe condition assessment (CCTV)
Stormwater sampling program with NLC in harbor watershed

(storm event and dry weather sampling)

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NLC Eelg lgrass Health Assessment and Stable Is Isotope Analysis

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NLC Eelgrass Restoration Project

Monomoy Beach Transplant Site 2012 Monomoy Beach Transplant Site 2018

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Fulling Mill March 2012

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Fulling Mill February 2018

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Monomoy March 2012

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Monomoy February 2018

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