By: Luis Enriquez

How Reclamation District 1000 Prevents Flooding and Keeps You Safe 

Every year the Natomas Basin gets showered with rain, whether it be significant or little rainfall. Depending on how significant the precipitation in California is, flooding can become an abrupt and critical issue. Why? The Natomas Basin is a low-lying region between the American River, Cross Canal, Natomas East Main Drainage Canal, and the Sacramento River. Because it is low-lying and surrounded by bodies of water, the Natomas Basin is one of the most at-risk regions for catastrophic flooding in the nation. Generally, the lower the altitude, the worse flooding can be. So, what if the Natomas Basin experienced a catastrophic flood? To understand the effects a flood would have, a brief review of the basin’s history is helpful. Let’s begin.  

Historical Context 

In 1862, before the urbanization of the Natomas Basin, the area was mainly farmland. Northern California was hit by a series of storms deemed “The Pineapple Express,” and relentless rain for weeks ensued. The result was devastating. The City of Sacramento was submerged under 30 feet of water, and countless lives and properties were lost. 1) The flood was caused by poor drainage of water from the valley. Subsequent reconstruction efforts raised modern-day “Old Sacramento” by 15 feet.  

Severe storms followed in the years 1986, 1995, 1997, 2006, and 2017. These storms brought abnormally high amounts of rainfall to the central valley and caused rivers to rise significantly. Despite the strain on the levees in the Natomas Basin, they remained relatively unharmed during these storms. 2) Levees are the walls bordering the river that contain the river and prevent it from overflowing as it flows through a valley. 

Beginning with the Gardenland neighborhood by the American River, the Natomas Basin began urbanization in the 1950s-1960s due to its proximity to downtown Sacramento and the potential for growth. Shortly after, the Sacramento Metropolitan Airport was built in 1967, followed by the construction of a new pumping plant to drain increased runoff from the airport. The North and South Natomas regions also saw expansion in business and residents in the 1990s. 3) As a mechanism to deal with the increased runoff from the significant urbanization, the district began using large storage detention basins to slowly seep runoff water into the main drainage systems and not overload them. 

Present Day Effects and Efforts 

A levee breach in the Natomas Basin could lead to widespread flooding, putting thousands of lives at risk and causing billions of dollars in damage. Since levees hold back water from rivers and canals, high water levels increase the chance of failure, making flood prevention crucial. A major flood could also disrupt national food supplies, as Northern California is a key agricultural region.  4) To mitigate flooding risks, the Natomas Basin relies on an interconnected system of canals, drainage ditches, pumping plants, and reinforced levees. These structures help manage excess water, directing it safely into the Sacramento River. Reclamation District 1000 (RD1000) plays a critical role in maintaining these levees by clearing vegetation, conducting regular inspections, and making necessary repairs. This upkeep prevents erosion and ensures levees remain strong under pressure.

Additional drainage systems, such as wetlands and retention ponds, help regulate water flow and reduce strain on levees. Wetlands absorb stormwater naturally, slowing runoff before it reaches the river. However, urbanization often limits space for wetlands, requiring alternative solutions like retention ponds. These man-made basins collect runoff water and release it gradually, preventing sudden surges that could overwhelm levees.

Despite these protective measures, some risk of levee failure remains. To further strengthen flood defenses, the Natomas Levee Improvement Project (NLIP) was approved in 2014. This large-scale effort upgrades 42 miles of levees surrounding the Natomas Basin, ensuring they meet modern safety standards for 200-year flood protection. The project, managed by SAFCA, the Central Valley Flood Protection Board, the U.S. Army Corps of Engineers, and RD1000, is expected to be completed in 2024.

1. “Active NorCalNorthern California’s Outdoor Digital Newsmagazine. “Remembering the Great Flood That Put Northern California Under 30 Feet of Water – Active  NorCal.” Active NorCal - Telling the Stories of Northern California, 31 May 2018, activenorcal.com/remembering-the-great-flood-that-put-northern-california-under-30-feet-of-water/. Accessed 19 October 2020 
2. “Presentation to the Floodplain Management Task Force.” Sacramento Department of Water Resources. Accessed 5 November 2020 
3. “Adapting to Urbanization.” Reclamation District 1000, www.rd1000.org/adapting-to-urbanization. Accessed 12 October 2020
4. ”Natomas Basin.” Www.spk.usace.army.mil, www.spk.usace.army.mil/natomas/. Accessed 5 October 2020