“Wetlands and riparian areas are among the state’s most valuable, most heavily impacted, and most threatened natural resources. They support a variety of beneficial uses and provide important water quality functions, including pollutant removal, flood attenuation and habitat.”

- State Water Board, 2003

Exploring Wetlands

• What is a Wetland?
• Why are Wetlands Important?
• Are Wetlands in Danger?

Different Kinds Of Wetlands

Exploring Wetlands

1. What is a Wetland?
   

   Wetlands are low-lying parts of the landscape that are covered by water for varying lengths of time.

   • Tidal wetlands are those parts of large water bodies, like the ocean, that occur at the transition between open water and uplands. High tides bring in water to cover the wetland and at low tide the wetlands are exposed to the air.
   • Other wetlands are located in upland locations and they are formed by depressions in the land that collect water during rain events and hold that water for varying amounts of time. Most dry up for some part of the year, a few can stay wet all year long.
   • Some upland wetlands are formed when adjacent rivers overflow and then those low areas collect and hold the water. Most plants do not like to be submerged under water and so a unique group of plants called wetland plants have evolved and often only those will live in a wetland. There are also wildlife species that require wetlands for their survival.

   Wetlands play a vital role in making the earth a good place for living creatures.

   There has been considerable debate, however, over the status of small upland wetlands, called isolated wetlands. Such small wetlands once were regulated and protected by the federal government, but court decisions and Bush Administration inaction resulted in rollbacks to this protection.

2. Why are Wetlands Important?
   

   Wetlands are one of our most valuable natural environments because:

   • Acre per acre compared to a field of wheat, wetlands produce more oxygen and more biomass (vegetation) through photosynthesis
   • Decaying w etland vegetation provides the base of most aquatic food chains
   • Over 75% of commercial and sport fish species are dependent upon wetlands at some point in their life cycle
   • Over 50% of our bird species depend upon wetlands at some point in their life cycle
   • Wetlands clean our water – contaminants in the water attach to the stems and roots of wetland vegetation and there microorganisms chemically alter those contaminants into non-harmful and in some cases beneficial chemicals - heavy metals are and other contaminants are trapped in wetland soils and are removed from interaction with humans, fish and wildlife
   • Surprisingly, wetlands also clean our air, the wetland vegetation taking in airborne contaminants
   • Wetlands help reduce flood damage by acting as sponges that absorb and collect stormwater and by slowing flood surges because of the slowing effect of wetland vegetation (Hurrican Katrina was so damaging because hundreds of thousands of acres of wetlands had been destroyed and so could not work against the flooding)
   • Wetlands play a vital role in climate change – while wetlands make up only 5% of the earth surface, they store (sequester) over 30% of the earth’s carbon. As wetlands are destroyed that carbon is released into the atmosphere in the form of CO2.
   • Wetlands help recharge our groundwater supplies, essential in many communities for agricultural and drinking water
   • Wetlands provide water to our steams and rivers
   • Wetlands support over 50% of our nation’s endangered species, including many rare plant species
   
   
   
3. Are Wetlands in Danger?

• Wetlands are often found in low-lying flat areas, areas that we have traditionally wanted for agriculture and housing. Because our forefathers did not understand the importance of wetlands, they destroyed over 51% of our nation ’s historic wetland acreage.
• In California we have lost an estimated 91% of our historic wetland acreage. Only in the last half of the 20th century did we realize how important wetlands were, as our rivers and streams saw increased pollution and the number of endangered species increased, as did flooding and loss of fisheries.
• The loss of wetlands was posing sever economic impacts to our nation. The passage of the federal Clean Water Act in 1972 saw the start of the protection of wetlands under the regulatory authority of the US Army Corps of Engineers and the US EPA.
• However, hundreds of thousands of acres of wetlands continued to be destroyed during the last half of 1900s.Only in the last two decades was the destruction of wetlands significantly slowed, although not at all stopped!!
• Two recent federal Supreme Court decisions (2001 and 2004) confused the issue of what is a federally protected wetland and as a result, the Army Corps and the EPA have decided not to protect most small upland, isolated wetlands that aren't connected to other water bodies.
  

   

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  Different Kinds Of Wetlands

1. What are Intermittent and Headwater Streams?

   Headwater streams make up more than 80% of total stream channel length in the United States. Often these small streams only flow during heavy rains or in the rainy seasons of those climates that don ’t have rain all year long and thus are called “intermittent streams." They are usually the beginning flows of larger streams and are thus are called “headwaters."

2. Why are Intermittent Streams Important?

   • Intermittent streams provide some of our most important water quality functions, removing contaminants and regulating nutrient, organic matter, and sediment movements before they reach our lakes and larger streams and rivers.
   • They support diverse wildlife that differ from those in larger downstream reaches
   • They also function as critical habitat or migration corridors for a multitude of amphibian, reptile, mammalian and bird species.
   

3. What is an Isolated Wetland?
   
   

   Small wetlands that are not located right next to a large body of water are considered isolated wetlands. They go by many names, for example, vernal pools, seasonal wetlands, and prairie potholes. When the Clean Water Act was written Congress included the word “navigable” to describe the waters the federal government would protect. It also defined “navigable waters” as waters of the United States. And so those who wanted to destroy wetland claimed that navigable meant that the government could only protect waters you could boat upon, while protectors of wetlands (including Congresspersons who entered a broad definition of navigable into the Congressional record) said that “waters of the United States” meant all waters including small wetlands and streams.

   For 30 years the Army Corps and EPA used the broader interpretation of “waters of the United States” and protected most of our upland isolated wetlands and small streams (although not doing this as well as for larger wetlands and streams). However, two federal Supreme Court decisions changed all this.

   
   
4. What is a Riparian Area?
   

   Riparian areas are the uplands adjacent to streams and rivers that are ecologically and hydrologically connected to the river or stream.

   • Riparian vegetation such as willows and tall shrubs grow on the banks of rivers and streams, providing shade that helps keep the water cool. This is essential for the survival of many fish species, such as salmon, that cannot withstand hot-water temperatures.
   • Riparian areas provide flood plains that help slow flood surges, and the vegetation in riparian areas help control flood surges.
   • Riparian areas provide essential habitat for many wildlife and plant species.
   • Riparian vegetation helps control sediment run-off.
   • Riparian areas play an important role in improving the water quality of our streams and rivers by removing impurities in water before they enter the streams and rivers.

   In the North Coast region of the state, riparian disturbance was identified as a major cause of 92% of high-temperature problems and 67% of sediment problems impairing the region’s streams and rivers.