Field Trip to the Stormwater Center at the University of New Hampshire

A keen group of engineers and town planners from Nova Scotia, an environmental engineer with Halifax Water and the Ecology Action Centre's Water Coordinator recently had the pleasure of visiting one of the leading stormwater research institutions in North America.  This trip was organized and funded by Nova Scotia Environment and the Climate Change Directorate as well as Service Nova Scotia and Municipal Relations.

The University of New Hampshire’s Stormwater Center (UNHSC) located in Durham, N.H. is dedicated to the protection of water resources through effective stormwater management.  One of the ways that UNHSC does this is through conducting primary field research on various stormwater treatment systems.  These include conventional systems such as swales and ponds, LID designs such as bioretention and gravel wetlands, and manufactured systems.  The image below shows the layout of their primary research site.

This stormwater research site collects water from a 3.6 hectare parking lot in Durham.  The stormwater is captured in the distribution box at the top of the image and equal volumes are piped to the various stormwater systems being tested.  Measurements from the outflow of the treatment systems are collected and tested at the sampling gallery at the bottom of the image.

Source: University of New Hampshire Stormwater Center, 2009 Biannual Report

The photos below show the various Best Management Practices (BMPs) on the site.

 Photo 1:
Manufactured system Stormtech Isolator in the foreground. Retention pond in the background.

Photo 2:
Dr. Ballestero from UNHSC standing in the Retention Pond

Photo 3: 

The Subsurface Gravel Wetland, slightly overgrown with vegetation.  The diagram below shows how the Subsurface Gravel Wetland works.

Source: University of New Hampshire Stormwater Center, 2009 Biannual Report

This method is one of the most effective ways of removing dissolved inorganic nitrogen and total phosphorous, as well as controlling peak flow.

Results from all of  UNHSC's stormwater BMP testing are available at the UNHSC website under publications.  

Nova Scotia's record rainfall

 Heavy rainfall events caused severe flood damage in Truro (Photo: Paul Palmeter, CBC, Sept  23, 2012)

From CBC News - October, 2, 2012:

September 2012 was the wettest September on record in Nova Scotia, with 386.8 millimetres of rain, according to Environment Canada.

The figures, released Monday morning, show rainfall amounts at the Halifax Stanfield International Airport smashed the previous September record — 308.7 millimetres, set in 1996.

This September's rainfall amounts are also very close to the all-time wettest month on record in the province — August 1971, when 387.1 millimetres of rain was recorded.

The last weekend of September proved to be a wet one for many Nova Scotians:

• Greenwood — 23.6 millimetres.
• Halifax Stanfield International Airport — 42.4 millimetres.
• Ingonish — 20 millimetres.
• Kentville — 27.6 millimetres.
• Malay Falls — 109 millimetres.
• Port Hawkesbury — 66.2 millimetres.
• Sydney — 18 millimetres.
• Upper Stewiacke — 45.2 millimetres.
• Yarmouth — 59.2 millimetres.

Earlier in September, heavy rains caused two rivers to overflow in the Truro area, forcing the evacuation of dozens of homes.

The area was pummelled with more than 75 millimetres of rain in one day, which caused more than $2 million worth of damage