News Archive

Minimizing Environmental Impacts Through Stormwater Ordinance and Site Plan Regulation

Friday, July 22, 2016

Using the Oyster River watershed as a pilot test case, this study evaluated the financial and ecological benefits of adopting the enhanced model stormwater standards to reduce future pollutant loads resulting from expansion of impervious area in the watershed over the next 30 years. The standards would apply to new development and redevelopment projects subject to site plan and/or subdivision review by the Planning Board. This includes most, if not all, commercial or mixed use development projects and residential multi-family or subdivision projects.

In addition to significant pollutant load reductions in the watershed, results found that early adoption of these model standards could result in substantial cost
savings through future cost avoidance in not having to construct numerous stormwater BMP retrofits to meet future regulations.

This research project was conducted by the UNH Stormwater Center in cooperation with VHB and the Strafford Regional Planning Commission (SRPC). The project was funded by EPA.

You can download a copy of the final report here:  Minimizing Environmental Impacts Through Stormwater Ordinance and Site Plan Regulation

You can also download a copy of the SWA Stormwater Standards here:  MODEL STORMWATER STANDARDS FOR COASTAL WATERSHED COMMUNITIES

And a recent collection of standard language updates tabulated from technical assistance efforts throughout this project here:

Model Stormwater Standards Addendum Spring 2016

UNHSC Innovative Bioretention Template for pollutant reductions in the Great Bay Estuary Watershed

Friday, July 22, 2016

The template combines up to date generic design information for innovative bioretention systems with updated cost and pollutant load reduction curves developed by EPA Region 1 and TetraTech in close collaboration with UNHS research staff.

The template can be viewed here:  UNHSC innovative bioretention design template

Additional information on the updated BMP performance curves can be found in Appendices F and H of the updated MA MS4 permit: 

EPA official tours stormwater projects at UNHSC

Tuesday, March 10, 2015

New Stormwater Management Systems Installed at UNH

Thursday, September 04, 2014

Durham, NH

Pollution from stormwater runnoff is a significant source of impairments to local water bodies.  The UNH Stormwater Center in partnership with UNH Facilities and the NH Department of Environmental Services are working to fix the problem.  The commuter parking lot know as A-lot represents the largest unmanaged expanse of pavement on the UNH campus (7.6 acres).  Through the implementation of innovative s bioretention and tree trench structures the UNH has managed much of the environmental impact this area had on local water ways.  UNHSC researchers estimate that the successful project will lead to the overall annual reduction of 83.3 pounds of total nitrogen, 12.3 pounds of total phosphorus, and 5,037 pounds of sediment load that originates from the area. 

UNHSC and UNH Facilities have been monitoring the parking area prior to the retrofit project.  Future research will continue monitoring to verify the effectiveness of the approach and develop a comparison of water quality pre- and post-project efforts.

This project is a direct follow up to the NHDES funded Municipal Bioretention Program that provided the optimization modeling and subwatershed pollutant load analysis by land use that were used to optimize management potentials in this project.

UNHSC updated porous asphalt specification

Tuesday, February 11, 2014


Thursday, November 14, 2013

For Immediate Release:

November 1, 2013


NEWINGTON, NH & DURHAM, NH—A high-impact, high-visibility rain garden has been installed in front of the Langdon Public Library in Newington, NH, by the UNH Stormwater Center (UNHSC). The library is currently undergoing a $1.79 million renovation and addition project.

The installation was part of the Great Bay Municipal Bioretention Program, otherwise known as “Biopalooza,” which was established through a partnership between the UNHSC and the Southeast Watershed Alliance (SWA) to assist watershed municipalities in implementing and tracking pollutant-load reduction through improved stormwater management.

Newington installation features a rain garden designed by Altus Engineering and provided to the town at no additional cost. The grant funded the materials, and the town road crew in cooperation with the Bauen Corporation (the builder for the Langdon Library renovation/addiation project) excavated and installed the system.

Langdon Library Director Scott Campbell remarked: “When Town Planner Tom Morgan informed me that Newington had received this grant, he described the type of situation UNHSC wanted to remediate – a high-visibility spot in need of beautification with a chronic drainage problem. I immediately pointed to “Lake Langdon.” 

The problem spot was a depressed triangle of clumpy, poorly growing grass in front of the library. It was not uncommon for the area to flood with up to a foot of standing water after a heavy rain, which would often take days to disperse. Compounding the problem is the fact that the town garage is just up the street, so this stretch of Nimble Hill Road gets heavily salted in the winter.

“We believe the rain garden will address the drainage problem while beautifying the area with appropriate plantings,” noted Melissa Prefontaine, chair of the Library Board of Trustees. “Since we were already redoing the parking and grounds for the new building, this project fit perfectly into the construction timeline.”

James Houle, program manager for the UNH Stormwater Center, noted: ”As communities become more dense, stormwater needs more sophisticated management. With these grants, we can help communities manage stormwater in ways that have multiple benefits.”

Before (top), during construction (middle) and after construction (bottom) pictures of the Newingto Bioretention system.



UNHSC woriking on implementing green infrastructure with local communities

Thursday, October 24, 2013

Congresswoman Carol Shea-Porter tours UNHSC projects in Rochester, NH

Sunday, August 18, 2013

Since partnering in 2009 UNHSC together with the NH Department of Environmental Services and the Cocheco River Watershed Coalition  have worked in the Willow Brook watershed that drains Rochester's urban core to disconnect paved surfaces and reduce harmful pollant levels.  Through two state funded projects the partnership has disconnected 1.4 acres of pavement and treat runoff through a variety of filters including vegetated gardens, permeable pavements, tree boxes and dry wells.  The efforts have led to annual reductions of 197 lbs of sediment, 0.7 lbs of phosphorus and 5.6 lbs of nitrogen.  You can read more about the visit here:  Fosters Article

UNHSC releases its final report on the performance of permeable interlocking concrete pavement technology

Thursday, August 08, 2013

The purpose of this study was to evaluate the cold climate functionality of a PICP in an institutional setting. You can access the final report by clicking the link below:


UNHSC to present progress on managaging pollution from stormwater on the Gundalo

Friday, June 28, 2013

with guest host JAMIE HOULE
from the UNH Stormwater Center
Join James Houle Program Manager and Outreach Coordinator, UNH Stormwater Center, to learn about local water quality issues and up-to-date solutions to pollution. Houle’s discussion will include success stories on implementation of innovative stormwater control measures.
This sail is FREE thanks to funding from RBC Wealth Management
* The Piscataqua is docked in Prescott Park, next to the historic Sheafe Warehouse *