Framing Action Around a Watershed

“No one city can affect the change needed to control large flooding events and likewise no one project will be enough to solve the problem.”

- Denham Strong Strategy for the Future , 2017, p.12

In 2016, Louisiana experienced two catastrophic rain events. The catastrophic August flooding in and around Baton Rouge took 13 lives and inundated more than 109,000 homes (LED 2017). In its wake there was an estimated $8.7 billion in damages requiring recovery efforts that will take years to complete. Though classified as a “one-in-1,000-year flood” this was the 3rd such event to hit the southeastern US in 2016, and one of 16 since 2010. Climate scientists predict that these types of severe rain storms are likely to increase in frequency and intensity in the future (Prein et al. 2016).

These two 2016 floods highlighted weaknesses in Louisiana’s approach to managing water and risk reduction. In response, the state has implemented the Louisiana Watershed Initiative. This effort coordinates state, regional, and local agencies to reduce flood risk by managing the flow of water along natural boundaries, and encouraging coordinated mitigation action across watersheds. Actions taken in one community can have a downstream impact on the flow of water−increasing or reducing the risk of flooding in other communities. At the same time, decisions about community development across a region are often uncoordinated and may be inconsistent with flood prevention. While in its early stages, the watershed approach will help to coordinate decisions about land use and infrastructure investment to more effectively manage flood risk. When thinking about planning at a watershed scale, these concepts set the framework apart: broad scales, systems, complex systems, and dynamic strategies.

watershed

A watershed is an area or ridge of land that separates waters flowing to different rivers, basins, or seas.

Watershed Approach Foundational Concepts

BROAD SCALES

Watershed planning units are defined by their environmental boundaries and functions rather than political boundaries. This can result in large land areas and many different communities being included in a single watershed.

COMPLEX SYSTEMS

Watershed planning includes all of the elements in a system (e.g. environmental, social, economic, infrastructural, and political) in the context of relationships with each other, rather than in isolation. This approach strives for biological, social, and economic diversity to protect the integrity of the whole system and promote resilience.

DYNAMIC STRATEGIES

Much like communities, watersheds are constantly changing through both natural and man-made processes. Planning for reduced risk and increased resilience requires monitoring and adaptation over time to address ever changing conditions.

planning

Planning is the process of deciding on and arranging in advance. It is also the formulation of long-range visions, goals, policies and strategies for achieving social, economic, and environmental sustainability in order to guide future community development.

watershed planning

Watershed planning provides a strategy for achieving resource and community goals related to water quantity and quality for an ecologically-defined system. The watershed planning process uses a series of cooperative, iterative steps to characterize existing conditions, identify and prioritize problems, define management objectives, and develop and implement restoration, protection, and monitoring recommendations at a range of scales.

As watersheds do not adhere to political boundaries, effective stormwater management requires collaboration across jurisdictional boundaries.

MISSISSIPPI

LOUISIANA

Denham Springs, Louisiana

The City of Denham Springs sits near the place where the Comite River merges with the Amite River on its way to Lake Maurepas. Emerging in the 20th century as a bedroom community to Baton Rouge, Denham Springs continues to attract families seeking to trade a twenty to thirty minute commute for the appeal of a smalltown atmosphere. Accordingly, most homes in Denham Springs are constructed in a single-family style, and businesses are concentrated along primary vehicular transit corridors. The City boasts a well-rated school system and is celebrated as the economic and cultural hub of Livingston Parish which, in recent years, has seen some of the fastest rates of population growth in Louisiana. Much of that growth is attributed to Denham Springs.

While its nearness to the Amite River proved instrumental for initial settlement and the agricultural industry, environmental changes−such as the expansion of development in the FEMA 100-year floodplain−have reduced the area’s capacity to absorb and manage stormwater that can accompany hurricanes and other large storms. These factors compound to significantly increase the severity and frequency of flood events in Denham Springs, which lies in the Amite Watershed.

Denham Springs’ streetscape, S. Range Ave.