Draft Nutrient Criteria for Great Bay Estuary

The New Hampshire Department of Environmental Services (NHDES) has developed numeric water quality criteria for the Great Bay Estuary. Numeric nutrient criteria were needed because New Hampshire’s water quality standards contain only narrative criteria for nutrients to protect designated uses. Narrative standards are difficult to apply for impairment and permitting decisions. NHDES received considerable assistance with the criteria development from the New Hampshire Estuaries Project (NHEP). The NHEP dedicated staff time to develop methods, formed a technical working group to review approaches and proposed criteria, and funded additional research to fill data gaps.
A variety of data sources were evaluated to provide multiple lines of evidence relative to appropriate thresholds for nutrients in the Great Bay Estuary. Each data source was chosen because of its relevance to the conceptual model for eutrophication in estuaries from the National Estuarine Eutrophication Assessment Update. A weight of evidence approach was used to combine information from the disparate sources. First, water quality measurements from different sections of the estuary were used to develop linear regressions between total nitrogen concentrations and chlorophyll-a, dissolved oxygen, and water clarity. Second, continuous monitoring of dissolved oxygen with in-situ sensors provided detailed information related to dissolved oxygen impairments. Finally, relationships between water quality and water clarity were quantified based on light attenuation measurements by in-situ sensors and hyperspectral imagery. Numeric criteria were developed for the aquatic life use support designated use because this use is the most sensitive to nutrient enrichment. NHDES considered low dissolved oxygen and loss of eelgrass habitat as the most important impacts to aquatic life from nutrient enrichment for the Great Bay Estuary. For each of these impacts, NHDES established a threshold for the total nitrogen concentration and a threshold for a response variable. Specifically, in order to maintain dissolved oxygen concentrations greater than 5 mg/L, the median total nitrogen concentration should be less than or equal to 0.45 mg N/L and the 90th percentile chlorophyll-a concentration during summer should be less than or equal to 12 ug/L. For the protection of eelgrass habitat, the median total nitrogen concentration should be less than or equal to 0.32 mg N/L and the light attenuation coefficient (a measure of water clarity) should be less than or equal to 0.75 m-1. Thresholds were not established for phosphorus because nitrogen is the limiting nutrient in the majority of the estuary.
The numeric criteria will first be used as interpretations of the water quality standards narrative criteria for NHDES’ Consolidated Assessment and Listing Methodology for 305(b) assessments. Later, NHDES will promulgate these values as water quality criteria in Env- Wq 1700. .
Read Draft Report and submit comments to philipl.trowbridge@des.nh.gov by February 9, 2009.

Using Moored Arrays and Hyperspectral Aerial Imagery to Develop Nutrient Criteria for New Hampshire’s Estuaries

In 2007, the NHEP received a grant from the U.S. Environmental Protection Agency to collect water quality information including that from moored sensors and hyper-spectral imagery data of the Great Bay Estuary. Data from the Great Bay Coastal Buoy, part of the regional Integrated Ocean Observing System (IOOS), were used to derive a multivariate model of water clarity with phytoplankton, Colored Dissolved Organic Matter (CDOM), and non-algal particles. Non-algal particles include both inorganic and organic matter. Most of the temporal variability in the diffuse attenuation coefficient of Photosynthetically Available Radiation (PAR) was associated with non-algal particles. However, on a mean daily basis non-algal particles and CDOM contributed a similar fraction (~30 %) to the attenuation of light. The contribution of phytoplankton was about a third of the other two optically important constituents. CDOM concentrations varied with salinity and magnitude of riverine inputs demonstrating its terrestrial origin. Non-algal particle concentration also varied with river flow but also wind driven resuspension. Twelve of the NHEP estuarine assessment zones were observed with the hyperspectral aerial imagery on August 29 and October 17. A concurrent in situ effort included buoy measurements, continuous along-track sampling, discrete water grab samples, and vertical profiles of light attenuation. PAR effective attenuation coefficients retrieved from deep water regions in the imagery agreed well with in-situ observations. Water clarity was lower and optically important constituent concentrations were higher in the tributaries. Eelgrass survival depth, estimated as the depth at which 22% of surface light was available, ranged from less than half a meter to over two meters. The best water clarity was found in the Great Bay (GB), Little Bay (LB), and Lower Piscataqua River (LPR) assessment zones. Absence of eelgrass from these zones would indicate controlling factors other than water clarity.
Final report unavailable online - pending academic publication. For more information, contact Ru Morrison at ru.morrison@unh.edu

Analysis of hyperspectral imagery for macroalgae and eelgrass mapping
This report outlines the configured procedure for mapping the macroalgae and eelgrass beds using hyperspectral imagery. No ground truth measurements of eelgrass or macroalgae were collected as part of this project, although eelgrass ground truth data was collected as part of a separate project. Guidance from eelgrass and macroalgae experts was used for identifying training sets and evaluating the classification results. The results produced a comprehensive eelgrass and macroalgae map of the estuary. Three recommendations are suggested following the experience gained in this study: conducting ground truth measurements at the time of the HS survey, acquiring the current DEM model of Great Bay Estuary, and examining additional HS datasets with expert eelgrass and macroalgae guidance. These three issues can improve the classification results and allow more advanced applications, such as identification of macroalgae types. Final report unavailable online - pending academic publication. For more information, contact Shachak Pe’eri at shachak@ccom.unh.edu

"Thanks for the maps and reports. What do we do with them?"
This report describes the efforts of Moose Mountains Regional Greenways (MMRG) personnel to assist local communities in establishing specific local priorities for land protection. MMRG staff conducted a total 32 meetings with conservation commissions, organized three regional workshops, created three sets of maps, conducted three field events, gave three presentations at lake association meetings, created six display booths and issued 12 press releases. Read Report

Total Nitrogen Concentrations in Wastewater Treatment Plant Effluent in the Great Bay Estuary Watershed in 2008

This report summarizes the NHEP effluent sampling program for nitrogen at eight wastewater treatment facilities (WWTF) in 2008. Facilities sampled were in Kittery , Berwick, Newmarket, Somersworth , Durham, Rochester, Exeter, and Dover. The Water Quality Analysis Laboratory at the University of New Hampshire processed the samples and the results, including daily average flow, total nitrogen concentrations, total dissolved nitrogen concentrations, and nitrogen loads for each WWTF are presented. Read Report

PREP Management Committee Meeting
12-15-08:The meeting focused on the update of the PREP Comprehensive Conservation and Management Plan. Facilitators Jack Mettee and Danna Truslow were on hand to vet draft goals and objectives developed by the PREP staff with Management Committee members. Other topics at the meeting included a presentation on economic indicators in the estuaries, nutrient criteria for the Great Bay Estuary, and Coastal Zone Management Act reauthorization. An orientation session was held for nine new committee members before the main meeting began.

Upcoming Events

	1-16-09: Second Annual Lamprey River Hydrologic Observatory Symposium, 8:30 a.m. - 4:00 pm, location UNH Memorial Union Building, Room 320 (see details below in Announcements)
	1-28-09: Stakeholder Meeting: Land Use and Habitat Protection #1, 9 a.m. - Noon, location Wells National Estuarine Research Reserve.
	2-4-09: Stakeholder Meeting: Living Resources & Habitat Restoration #1, 9 a.m. - Noon, location UNH Cooperative Extension Office, Brentwood, NH.
	2-19-09: Stakeholder Meeting: Water Resources #2 9 a.m. - Noon, location Urban Forestry Center, Portsmouth, NH
	3-5-09: Stakeholder Meeting: Land Use and Habitat Protection #2, 9 a.m. - Noon, location Exeter Public Library, Exeter, NH.
	3-19-09: Stakeholder Meeting: Living Resources & Habitat Restoration #2 9 a.m. - Noon, location NHDES Coastal Office (Pease), Portsmouth, NH.
	4-1-09: Stakeholder Meeting: Water Resources #3 1-4 p.m., Nh Fish and Game Region 3 Office, Durham, NH
	4-15-09: Stakeholder Meeting: Land Use and Habitat Protection #3 1-4 p.m. location Hugh Gregg Coastal Conservation Center, Greenland, NH
	4-29-09: Stakeholder Meeting: Living Resources & Habitat Restoration #3 1 - 4 p.m., location Urban Forestry Center, Portsmouth, NH.
	10-16-09: 2009 State of the Estuaries Conference 8 a.m. -4 p.m., location to be determined.

Announcements

Second Annual Lamprey River Hydrologic Observatory Symposium
This symposium will highlight several studies conducted by the UNH community using the Lamprey River watershed. Participants will leave with a greater appreciation for the complexities of the watershed and the interrelationship of multiple natural resources and human interactions. An agenda can be requested from Michelle Daley at michelle.daley@unh.edu. Parking is available on a first-come, first-serve basis in C lot. All-day parking is $8. Lamprey River Watershed Association will pay the parking fee for members in C lot. The symposium will be in the Memorial Union Building, Room 320.

NH Sea Grant RFP
The New Hampshire Sea Grant College Program announces the release of its 2010-2011 NOAA Omnibus Request for Proposals. Proposals should address one or more of the marine-related issues identified in the NH Sea Grant Strategic Plan. New Hampshire Sea Grant seeks to foster the highest quality marine research, education and extension efforts, creative and rigorously conceived proposals in areas not mentioned in the Strategic Plan are welcomed. All proposals should contribute to improved understanding, utilization and/or management of coastal and marine resources. We strongly recommend that researchers seek to work with and integrate Sea Grant extension educators into their projects. Pre-proposals are due on March 2, 2009 through an electronic submission procedure. Direct general questions to Linda Wade (linda.wade@unh.edu – 603-862-2987) and programmatic questions to Steve Jones (shj@unh.edu – 603-862-5124).

NH Coastal Program Accepting 2009 Competitive Grant Applications
Yearly, the NH Coastal Program at NHDES awards federal funding to projects that address coastal resources, like water quality protection, public access and education. Grants are offered on a competitive basis to eligible applicants, and at least a one to one match is required. The maximum grant award amount has changed from past years given reduced federal funding for this program. No more than $40,000 will be awarded for any construction or land acquisition project, and no more than $30,000 will be awarded for any planning or management project. Two print copies and an electronic copy of the completed application and all associated documentation (including letters of support) are due at the NH Coastal Program office no later than Monday, January 26, 2009 at 4:00 p.m. see NH Coastal Program website for details.

Climate Ready Estuaries Newsletters and More
Learn about Climate Ready Estuaries projects at www.epa.gov/cre/

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