The Milwaukee River lacks bank vegetation and natural habitat for macro-invertebrates and many fish species because it is lined with steel sheet piling or concrete. In order to improve the spawning and habitat conditions, floating islands were implemented in some areas of the river. The floating islands are made of both synthetic and natural material, benefiting plant growth. Then, algae and biofilms quickly colonize the structures, creating food for zooplankton, and then small fish. The floating islands are designed to provide heavy vegetation providing food, oxygen, and shelter to the fish that are heading upstream to spawn or just passing through. Even more, these structures mimic wetlands, which 80% of native Great Lakes fish species depend on.
The hardened shorelines of the Menomonee, Kinnickinnic, and Milwaukee Rivers make it extremely difficult for plants to grow along the bank. Moreover, because of heavy ship traffic in these urban waterways, many of the river bottoms were dredged, leaving both the shoreline and bottom regions an aquatic desert. Therefore, Groundwork Milwaukee has introduced several floating islands, as well as over 200 habitat underwater baskets in each of the 3 rivers leading to Lake Michigan. These baskets are designed to house plants in-between the corrugations of the sheet piling, introducing food and shelter for fish passing through.
The Chicago River habitat also suffers from its urban location, usage, and lack of natural vegetation on its riverbank. Thus, the Chicago River walk introduced Fish Hotels. These are fish habitats that provide a portable or permanent habitat that can support algae and macro-invertebrates. Fish hotels provide food and shelter for fish traveling through the river.
The final phase of Chicago’s Riverwalk is underway, containing innovative features for those living above and below the water. The Jetty is designed to be a floating wetland that will bring a healthy habitat to better support the Chicago River’s fish, while providing recreational and educational opportunities to visitors. Building off the idea of a fish hotel, they will be introducing what they call a pole hula. The small metal structure with ropes attached allows for algae to grow and macro-invertebrates to take hold. Additionally, the plants that will float on the surface will further provide areas for biofilm to grow. With the addition of floating gardens/islands, the floating wetlands will allow for vital fish habitat.
Chicago is home to many businesses and industrial buildings along its waterways. Moreover, on top of the river’s lack of diversity and habitat, and the polluted state in many areas, there is little public access to the water and awareness about its health. Therefore, if people had a close tie to the river, people would have an incentive to maintain it properly. Chicago plans to incorporate an interactive kayak park to further engage the public. The once native, now extinct, Freshwater Mussel was the inspiration for the park design. The park would feature a kayak launch, floating pool barge, performance stage, and murals. Moreover, the park would be home to floating islands of native grasses and would greatly increase the wildlife habitat within the space.
The Cuyahoga River flows through a heavy industrial area of Cleveland that handles large ships and barges. Like other Great Lakes shipping regions, the steel and concrete holding the riverbanks together and the dredged river bottoms lack proper fish and wildlife habitat. The Cuyahoga River is the passageway for fish to enter Lake Erie and without appropriate habitat; spawning and fisheries are negatively impacted. Therefore, in 2015 and 2016, gated structures were put in place along the river wall that provides food and shelter from predators.
To improve the shoreline of the Hudson River, FishHEDs were introduced. The fish habitat enhancement devises are designed with steel and mounted on the harbor wall with brackets. The structures hang in the water and provide alternative spaces for macro-invertebrates and fish to congregate.
Baltimore’s Inner Harbor has lacked refuge vegetation and habitat for fish passing through. Therefore, Biohuts were installed on the bulkheads of the harbor. A Biohut consists of a double layer cage. The innermost portion is filled with oyster shells. These shells attract microorganisms, which quickly colonize the area. The oyster shells contain juvenile oysters, which can grow and filter out algae from the water. Then, barnacles and mussels can attach to the shells and structures, further filtering the water. The outermost cage offers a predator-free zone for any juvenile fish.
In the 1900s, the Elliott Bay Seawall was constructed, destroying 68% of the shoreline habitat in Seattle. Much of the habitat was devastated, reducing salmon populations by 90%. Therefore, a major seawall reconstruction project could recover salmon populations. For example, sidewalks, piers, and other out jetting structures shroud 60% of the downtown shoreline with darkness. Because juvenile salmon have poor sight in the dark, they tend to avoid the structures by swimming into deeper waters where harbor seals easily prey them on. Thus, the new sidewalk is designed to have glass blocks and grates to allow light to enter the water below. Moreover, the added light will allow more plants to occupy the floor and walls of the shoreline. The plants will allow for algae and macro-invertebrates to take hold, providing food for the organisms and fish passing through. The greening of the Seattle’s waterfront will also improve water quality, help to reduce shoreline erosion, and give people access to a beautiful shoreline. Finally, the Seawall Project will include an underwater bench. Elliott Bay is deep for large ships to pass through; however, juvenile salmon prefer shallow waters. Therefore, a shallow region will extend from the Seawall and create a migration corridor for the salmon.
The Lower Don Lands consist of 308 acres of Toronto waterfront that has been neglected over the years, as it is part of a shipping channel. The vision for this space includes merging the urban and natural environments to meet the cities’ sustainable and community goals.
Downtown Toronto’s southeastern region could be easily overwhelmed by floodwaters in an extreme weather event. In fact, 290 hectares are at risk of flooding from the Don River. Therefore, it is proposed that the Don River be reconnected to Lake Ontario by creating a river mouth. This project would include over 1,000 m of new river channel, 13 hectares of new wetland, 5 hectares of terrestrial habitat within the constructed valley, and the enhancement of 14 hectares of aquatic habitat. The new river mouth will remove the flood risk to 240 hectares of land.
Toronto has several parks that will help connect the public with the environment. The Corktown Common Park will offer a diverse range of experiences and both views of the city and natural habitat. The park contains playgrounds, a splash pad, and an athletic field. Moreover, the park is home to over 700 trees and thousands of shrubs, groundcovers and aquatic plants. The ecological richness of the park will aid in plant and animal biodiversity. Additionally, the marsh will provide both an onsite storm water management system and a habitat for birds, amphibians, and insects.