Existing Land Use

There are many opportunities for improving existing conditions throughout the Warner River watershed to preserve our wild brook trout and water quality. Many improvements can occur along our river and streams, other improvements can be made within our more dense and downtown areas, which become heat islands that warm stormwater and discharge it directly into streams.

Improve Habitat by Protecting & Reinstalling Forested Stream Buffers
The influence of land use on aquatic habitats within a watershed has been well documented.  An insufficient vegetated buffer along river banks has contributed to bank erosion and sedimentation. Coldwater streams flowing through agricultural areas often lack fully functioning riparian buffers due to stream side mowing or grazing activity.

Riparian Buffer Protection is the most effective and economically feasible practice to protect aquatic habitat and water quality. Forested stream buffers can be achieved through voluntary land use practices (such as agricultural and forestry best management practices), town ordinances, state law (i.e. The Shoreland Water Quality Protection Act and the Rivers Management and Protection Program (RMPP), deed restriction and conservation easements.

In general, the wider forested stream buffer, the greater the ecological benefit. A forested buffer of at least 10 m (32.8 ft) will provide a minimum level of water quality and habitat benefits. A 2014 scientific article in the Journal of the American Water Resources Association, Streamside Forest Buffer Width Needed to Protect Stream Water Quality, Habitat, and Organisms: A literature Review, evaluated riparian buffer width effectiveness using eight different criteria to determine the best width for protecting habitat and water quality. They determined that for the size of the Warner River and smaller streams, widths 30 m (98.4 ft) or more is necessary to protect the physical, chemical and biological integrity. A protected buffer of 100 m (328 ft) or greater provides maximum water quality and habitat benefits while also acting as a migration corridor for larger species of wildlife. Buffer protection is lacking on headwater streams despite the cumulative effect that intact riparian zones in headwater streams have on downstream water quality.

Protecting and Managing Forests in Drinking Water Source Watersheds is essential to providing clean, safe drinking water that we can afford in the future. Water treatment alone is no longer perceived as a single method to secure drinking water supply. Preserving our forests to treat our water and maintain high water quality is much less expensive. To learn more, read the USDA report Forests, Water and People: Drinking water supply and forest lands in the Northeast and Midwest United States.

Resources
Healthy Watersheds: Protecting Aquatic Systems through Landscape Approaches
Native Shoreland and Riparian Buffer plantings for NH Adobe Acrobat Reader Symbol
Shoreland Protection Fact Sheets

Practice Best Management Habitat Stewardship

Improving Habitat by Updating or Removing Existing Infrastructure

Replace Undersized Culverts at Road-Stream Crossings – Poorly sized stream crossings alter the natural sediment transport characteristics of a river or stream, which leads to erosion and excess sediment deposition in the stream channel. The cumulative effect of under sized stream crossings can lead to increased sedimentation and turbidity throughout a watershed during storm events. Road fill from washed out stream crossings during flood events accumulates in the stream channel and buries the natural stream bed substrate. Observations of stream crossings during fish surveys in New Hampshire suggest that there are very few streams that do not show some habitat damage from stream crossings.

Improve Habitat by Addressing the Flow Regimes of Existing Dams
River and stream habitat below lakes and ponds may be impacted as flows are shutdown in an attempt to refill lakes or increased rapidly to lower the water level. Surface waters impounded by dams are generally exposed to solar radiation and typically exceed the temperature tolerance of coldwater fish. Dams on coldwater rivers and streams not only fragment habitat, but increase water temperatures both upstream and downstream of the impoundment. Changes in fish and invertebrate communities that result from artificial flow manipulation involve a shift to habitat generalist species. These changes have been have been well documented in studies related to instream.

Dam removal projects on coldwater streams should target dams that either fragment large networks of coldwater stream habitat or dams that create unsuitable water temperatures for coldwater species. Once a dam is identified for removal, the process is the same as it is for projects targeting diadromous fish restoration. A dedicated project manager is critical for meeting permitting deadlines and managing the many issues that often arise during dam removal projects, such as contaminated sediment removal or historical resource documentation at the site. Despite efforts to prioritize, dam removal projects often come up opportunistically as smaller dams fall into disrepair and become expensive to maintain or repair. Grant funding for dam removal projects is available, but limited, so resources should be directed at projects with the greatest benefit to coldwater stream habitat.

Infiltrate Stormwater Runoff & Pollution

Minimize Point-Source Pollution (pipes that discharge directly into our waterbodies)Industrial pollutants and pollution that directly discharge untreated wastewater into waterbodies from pipes have been greatly reduced since the passage of the Clean Water Act. However, there are still isolated areas such as Superfund Sites or combined sewer overflows (CSO’s) where pollutants continue to enter aquatic habitats at known locations.

Install Low Impact Development techniques and Green Infrastructure (like rain gardens and tree box filters to infiltrate stormwater where it falls, thereby allowing soil microorganisms to break down pollutants and cool stormwater temperature before reaching our rivers and streams.

Resources for Pollution & Stormwater Management
NH Soak Up the Rain a great resource for homeowners.
UNH Stormwater Center (UNHSC)leads the nation for their research and implementation of Low Impact Development (LID) practices for stormwater management.
UNHSC’s Thermal Impacts, Stormwater Management, and Surface Waters

Successful Watershed Projects Utilizing LID techniques to Improve Watershed Health
UNH SC’s Urban Watershed Renewal in Berry Brook, an Examination of Impervious Cover, Stream Restoration and Ecosystem Response, Dover, NH

Minimize Habitat Degradation caused by Recreation

Logging Road, OHRV & Snowmobile Trail Crossings and private roads frequently cross coldwater river and stream habitat. These crossings, which can consist of either temporary or permanent structures, are often less regulated than those crossings maintained for public roads and can cause fragmentation and sedimentation. When crossings are not designed according to the specific geomorphology of a stream, local bank erosion, stream bed scouring, and sediment deposition can occur. At a watershed scale, the cumulative effect of these crossings on headwater streams may increase sedimentation issues downstream.

Effects of stream crossings over logging roads and recreational trails vary significantly by site and construction. Many logging road crossings are temporary, but may cause significant erosion and sediment deposition to a stream before they are removed. Often snowmobile clubs build bridges that have very little impact on a stream. However, undersized culverts can cause long term habitat degradation and restrict the movement of species in areas with permanently constructed trail networks. The cumulative impacts of privately constructed road stream crossings in a watershed have not been well studied.

Keep trails out of sensitive habitats and a good distance away form river and stream banks to avoid damage to native riparian. Frequently trafficked areas are more prone to bank failure and erosion.Practice trail building techniques that minimize runoff and infiltrate stormwater.

Take Action to Minimize the Spread of Invasive Species

Exotic Aquatic Species – Whether they are accidental or intentional, invasive aquatic species introductions are notoriously difficult to prevent and even more difficult to control. NHDES, NH Lakes Association and other individual lake and pond groups have had some success preventing invasive aquatic species introductions with public outreach and by staffing boat ramps with trained inspectors, called Lake Hosts. Prevention and early detection is the most effective strategy for limiting the spread of invasive species. Once an introduced species has become established it is nearly impossible to eradicate it. Management efforts to control the species can be costly and requires long term planning.

An angler determined to create a new fishing opportunity by stocking a new fish species into a waterbody is hard to deter. Education on the ecological damage that can be caused by introducing nonnative species into a waterbody will help prevent some, but not all deliberate species introductions. In some cases, anglers invested in the existing fishery may make the best advocates against new species introductions. However, outreach will not persuade everyone, so laws, penalties, and adequate funding for enforcement are the last line of defense against species introductions. It is important that penalties are severe enough and the presence of law enforcement is noticeable enough to act as a deterrent. New species introductions are inevitable, but the rate and overall extent of introductions may be contained.

Prevent spread of these species by cleaning, draining and drying your boat, your boots and fishing gear to prevent spreading invasives from one waterbody to another. Learn to identify species and reporting infestations to your local conservation commission.

Become a Citizen Scientist or NH Rivers Council River Runner to be able to identify invasive species when you are kayaking, fishing or hiking in the watershed.

Early Detection & Distribution Mapping (EDD Maps) provides both an online and mobile app resources that aid in field id and reporting of any kind of invasive plant or species. Locations and sizes of infestations can be mapped to improve communication and coordinate eradication efforts across multiple parties and agencies.

Resources Pertaining to Aquatic Invasive Plants & Species

Exotic Terrestrial Species – These alien plant species take advantage of our ecosystems in the same way as aquatic plants, although typically take root along our major highways, public utility corridors and other areas of land disturbance.

Exotic Insects & Diseases

  • NH Bugs provides up-to-date information on Damaging Insects and Diseases in NH