Fitchburg Nature-Based Solutions

The City of Fitchburg is continuing to implement   projects to improve climate resilience . Climate change is already impacting our community through increasingly, frequent and intense rain events. This results in flooding, heat, and extreme storms that disrupt daily activity, hurts business, and puts our safety at risk.

One major climate resilience project, started in 2022, is developing a resilient drainage system for downtown Fitchburg, funded by   the State's Municipal Vulnerability Preparedness (MVP) Grant Program . 

Other MVP funded projects started in 2023 include:

1) A Nashua River Watershed Association-led planning project to help Fitchburg and neighboring communities identify Nature-based Solution (NBS) sites and examples to combat the effects of climate change across the City.

2) A downtown-specific Climate Adaptation Action Plan being developed by the City for the Urban Revitalization Area (URA). The Climate Adaptation Action Plan will enhance the City’s ambitious, 20-year redevelopment plan to reclaim the Nashua River as a major economic and recreational asset.

This StoryMap page details below a range of NBS and the progress of the NBS installations in Downtown Fitchburg.

The problem: Historically, areas of downtown Fitchburg have had high exposure to riverine and urban flooding. Taking into account future precipitation, nuisance flooding as well as significant flooding events are expected to happen more frequently. The City has been retrofitting their current drainage system to separate sewer and stormwater in an effort to improve water quality. However, the prominence of impermeable surfaces within downtown and increasing precipitation will continue to stress the stormwater drainage system.

The solution: The City is installing nature-based solutions (NBS), that include green infrastructure (GI), in an effort to lessen the impact of major flooding the piped, stormwater system, and local roads and streams. Nature-based solutions are surface solutions that can intercept, treat, delay, or store stormwater before it enters a pipe. They are intended to complement the existing drainage system and incorporate natural systems to reduce impacts of climate change, such as flooding, urban heat island, and erosion.

The goal of this project: to make downtown Fitchburg more resilient to future climate change impacts.

Questions? Comments? Contact Nick Erickson, Commissioner of Public Works and City Engineer (nerickson@fitchburgma.gov) or share your comments on the comment form.

Real examples of climate resilient Green Infrastructure are right in our backyard - Find GI in Fitchburg on this map. Zoom in on Tree Trench 1 to reveal additional GI sites.

See something at an NBS site that needs attention? Tell Us Here:

Rain and storm events are increasing!

In Fitchburg, the frequency of heavy rain events has increased in recent years. Recent intense storms have washed out roads and increased flooding on streets and private properties. Heavy rain events are predicted to occur more often in the future, due to climate change.

Stormwater runoff can cause flooding and erosion! Flooding occurs where increased rainfall amounts saturate the soil and cannot be fully absorbed. Flooding also occurs where rain or snow melt runs off hard surfaces such as roadways, parking areas, and even roofs more quickly than it would naturally. Stormwater flows to the nearest water body or low-lying area, resulting erosion, quickly rising river levels, and flooding. Stormwater also collects pollutants on the land surface such as trash, pet waste, oils from leaking vehicles, and even sand/sediment, carrying pollution to local wetlands and waterbodies.

Use the slider feature below to toggle between existing and proposed NBS locations. Dragging the <> in the middle of the map to the right will show you only existing sites while dragging to the left will show both existing and proposed sites. Click on a site to learn more about a specific NBS project.

The nature-based solutions toolkit below details various types of nature-based solutions that Fitchburg considered for downtown flood mitigation.

As part of ongoing street work and combined sewer overflow separation improvements in this downtown project area, the City has identified additional improvements to help reduce stormwater and urban heat effects.

A field visit to the project area investigated stormwater manholes and catchbasins projected to flood and possible locations for nature-based solutions to maximize the collection of stormwater runoff.

The team conducted outreach and gathered data from the community during the project’s design process to gain a greater understanding of how flood prone areas affect daily life. Although stormwater modeling provides a strong representation of the flooding issues experienced in Fitchburg, the team wanted to confirm the results against local knowledge in the community. From this feedback, they were able to better understand potential improvements required to mitigate flooding issues.

A two-minute video titled, “Creating Cooling and Flood Reduction Solutions for Downtown Fitchburg” provided residents with information about the project focus area, project plan, potential solutions and benefits, and opportunities for feedback. The video was translated in Spanish to reach a wider audience.

An ArcGIS 123 survey was launched to seek ideas for planning improvements in the downtown neighborhood. Residents were asked to share top priorities related to flooding, heat, or things to preserve. The survey received two responses. Top priorities for projects included the following:

• Fields
• Parking lots
• Parks
• Plantings
• Safety Enhancements
• Sidewalks/Street Sides
• Trees/Shade

View the  video (English) ,  video (Spanish) , and  survey results .

The ambient air temperature Urban Heat Island (UHI) map for Fitchburg was used to evaluate the cooling benefits of green infrastructure implementation in selected locations around the City. Green infrastructure increases the permeability of the land in the form of bioretention, pervious paving, conveyance swales, etc. The cooling impact of green infrastructure on urban heat island was determined by comparing the change in ambient air temperature as a function of change in impervious cover in the City.

The result shows that a temperature decrease of up to 4°F can be achieved by decreasing the impervious area from proposed green infrastructure implementation. This demonstrates that green infrastructure strategies can be effective in mitigating UHI effects, which in turn can alleviate significant public health impacts on extreme temperature days.

The NBS focused on strategies to mitigate localized flooding and incorporate increases to tree canopy, surface stormwater conveyance, detention, infiltration and daylighting. The opportunities selected were those identified to optimally perform during a Year 2070 SCS 10-Year, 24 hour storm event.

In 2023 and 2024, 92 opportunities were identified and scored between 1 (no impact) to 5 (high impact) for each co-benefit. The matrix was created with the co-benefits listed below to assign a priority score for each parcel. Utilizing this matrix, parcels were prioritized, and the top sites were chosen for further evaluation for preliminary public green infrastructure designs and conceptual private green infrastructure designs.

The following Co-Benefits were factored into the Prioritization Matrix:

1. Flood Reduction benefits: The efficiency of the NBS to reduce flooding to the sub-watershed.  This is reflected by the % reduction of total volume during the 2070 2-year storm event.

2. Environmental Justice Community: Proximity of parcel to Environmental Justice Communities.  Projects located closer, and therefore having a greater ability to reduce flooding to EJ communities, rated higher. 

3. Reduction of Urban Heat: Potential for improvements to also reduce UH by creating green spaces, increased vegetation or removal of impervious

4. Ease of Implementation: Ability for the city to complete the work in a timely and efficient manner.  Including access, ownership, fewer development obstacles.

5. Pedestrian Improvements: Provides additional open space opportunities or access to pedestrians to the site.

6. Biodiversity/Habitat: Potential ability to increase habitat or biodiversity within the site

7. Opinion of Probable Cost: Cost to construct, operate and maintain each NBS

8. Public Preference: Data driven from multiple public engagement events including pop-up, public meetings, and online survey.

Although each site was evaluated along these nine factors, each factor was also weighted differently based on the city’s understanding of which factors were more valuable in actually getting these projects constructed.  For example, the entire project area falls within an environmental justice neighborhood and is therefore not a distinguishing co-benefit to be highly weighted.

Once the sites from Phase 1 were scored and ranked for flood mitigation and co-benefits, several sites were recognized as highest priority. These sites were designed and installed in 2024. Additional sites from Phase 2 will be evaluated for feasibility in future phases.