Wetlands and Wetland Restoration in California

Wetlands are one of California’s most vital and yet most threatened ecosystems.

These unique landscapes play a critical role in maintaining biodiversity, filtering pollutants, controlling floods and replenishing groundwater.

However, due to urban expansion, agriculture, and industrial development, California has lost over 90% of its historical wetlands, making restoration and conservation efforts more crucial than ever.

This guide serves as a foundational background to help readers understand what wetlands are, why they matter and how restoration efforts are shaping California’s ecological future.

The next, more targeted articles in The Daily Muck’s investigative series will link back to this overview as we uncover the fraud, failures and fights surrounding wetland restoration efforts in a state that used to be the beacon for environmental care and protection.

What happened, California?

What Are Wetlands?

Wetlands are areas where water covers the soil or is present near the surface for at least part of the year. They exist in the transition zones between dry land and bodies of water, providing a unique habitat for plants and animals adapted to both land and aquatic environments.

Types of Wetlands in California

California is home to diverse wetland habitats, each serving different ecological functions:

1. Coastal Wetlands – Found along the Pacific coastline, these wetlands protect shorelines from erosion, act as nurseries for marine species, and absorb storm surges. Example: San Francisco Bay salt marshes.
2. Freshwater Marshes – Inland wetlands fed by rivers, streams, or groundwater. They support a variety of plant and animal life and help improve water quality. Example: Sacramento-San Joaquin Delta wetlands.
3. Vernal Pools – Seasonal wetlands that appear in winter and spring but dry up in summer. These rare habitats support specialized species, such as fairy shrimp.
4. Riparian Wetlands – Found along riverbanks, these wetlands play a key role in stabilizing soil, preventing erosion, and providing wildlife corridors. Example: Los Angeles River riparian zones.

Ecological Functions of Wetlands

Wetlands are often called “nature’s kidneys” because they filter pollutants and improve water quality.

They also serve as carbon sinks, capturing and storing carbon dioxide, which helps mitigate climate change.

And their most important function, wetlands provide crucial habitats for birds, fish, amphibians and plant species, many of which are endangered or threatened.

Why Are Wetlands Important?

Despite covering only a small percentage of the landscape, wetlands provide a disproportionate value to both humans and wildlife.

Their importance can be grouped into three main categories of benefits:

1. Ecological

• Biodiversity Hotspots – Wetlands support a vast array of species, including migratory birds, amphibians and fish. The California delta smelt and salt marsh harvest mouse depend on wetland ecosystems for survival.
• Water Filtration – Wetlands remove excess nutrients, heavy metals and pollutants from water before it reaches larger bodies, reducing the need for costly filtration systems.
• Climate Change Mitigation – Peatlands and marshes store carbon in their dense plant matter, helping offset greenhouse gas emissions.

2. Hydrological

• Flood Control – Wetlands act as natural sponges, absorbing excess rainwater and reducing the impact of floods.
• Groundwater Recharge – Many wetlands help replenish underground aquifers, ensuring long-term water supply sustainability.
• Coastal Protection – Coastal marshes and estuaries buffer storm surges and rising sea levels, preventing erosion and property damage.

3. Economic and Recreational

• Fisheries & Agriculture – Wetlands provide breeding and feeding grounds for commercially important fish and shellfish, supporting the fishing industry.
• Tourism & Recreation – Birdwatching, kayaking, and eco-tourism contribute to local economies, generating millions in revenue annually.
• Property Value & Livability – Communities near healthy wetlands benefit from improved air and water quality, as well as reduced flood risk.

Wetland Loss in California

Historically, wetlands covered vast areas of California, but since the 1800s, more than 90% have been lost due to:

• Agricultural Expansion – Wetlands were drained to create farmland, particularly in the Central Valley.
• Urban Development – Cities and infrastructure replaced natural wetland areas.
• Industrial and Water Management Projects – Dams, levees, and water diversions altered natural water flow, disrupting wetlands.

The loss of wetlands has led to declining biodiversity, increased flood risks and reduced water quality, making restoration efforts essential.

The “No Net Loss” Policy

Recognizing the importance of wetlands, the U.S. and California governments adopted the “No Net Loss” policy under George H.W. Bush, which requires that for each acre of wetland lost another acre of wetland must be restored.

Key Agencies Involved:

• U.S. Army Corps of Engineers
• Environmental Protection Agency (EPA)
• California State Water Resources Control Board

This policy helps balance development and conservation by ensuring wetland functions are maintained or enhanced.

Wetland Restoration in California

With over 90% of California’s historical wetlands lost, restoration efforts have become a top priority to rebuild critical habitats, improve water quality, and combat climate change.

Wetland restorations focus on restoring natural hydrology, reintroducing native vegetation and rebuilding habitats to support wildlife and ecological functions.

Key Approaches to Wetland Restoration

Restoration projects vary depending on the wetland type and level of degradation but typically involve:

1. Hydrological Restoration – Removing levees, dams or other barriers to restore natural water flow.
2. Tidal Marsh Restoration – Reconnecting wetlands to the ocean to revive coastal ecosystems.
3. Native Plant Reintroduction – Restoring local plant species to improve soil health and habitat quality.
4. Wildlife Habitat Enhancement – Creating conditions that support fish, birds, and amphibians.
5. Invasive Species Removal – Eliminating non-native plants that choke out natural wetland species

Wetland Mitigation and Mitigation Credits

Wetland mitigation is a key component of California’s No Net Loss policy, requiring developers to offset any wetland destruction by restoring, enhancing or creating new wetlands elsewhere.

While this system is intended to balance conservation and development, its effectiveness depends on accurate reporting, proper oversight and real ecological success.

How Wetland Mitigation Works

When wetlands are impacted by construction or development, federal and state laws require developers to compensate for the loss by:

1. Restoring degraded wetlands to their natural state.
2. Enhancing existing wetlands to improve their ecological function.
3. Creating entirely new wetland areas.
4. Preserving high-value wetlands at risk of future destruction.

Mitigation can be permittee-responsible (handled directly by the developer) or bank-based, where developers purchase mitigation credits from pre-approved restoration projects.

Mitigation Credits and Wetland Banks

Mitigation banks are areas of restored, enhanced, or created wetlands pre-approved to generate “credits” that developers can purchase to offset their environmental impact.

These credits are measured in acres or functional value and are typically managed by private companies, conservation groups, or public agencies.

• Developers buy credits instead of restoring wetlands themselves.
• Regulators approve mitigation banks based on their restoration success.
• Credits are limited to ensure ecological balance—though over-reporting can be a problem.

The Role of Programmatic Agreements in Wetland Conservation

One of the key mechanisms for streamlining wetland restoration, mitigation and regulatory compliance in California is the use of Programmatic Agreements (PAs).

These agreements are formal, long-term arrangements between government agencies, tribal entities, conservation organizations, NGOs and sometimes private developers, aimed at simplifying and expediting environmental review and permitting processes for projects that impact wetlands.

What Are Programmatic Agreements?

A Programmatic Agreement is a legal framework established under federal and state environmental laws to address repetitive or large-scale impacts on natural resources, including wetlands.

Instead of reviewing each project individually, agencies set up pre-approved procedures and mitigation measures that apply to multiple projects over an extended period.

How Programmatic Agreements Work

• Pre-Approved Mitigation Plans – Instead of assessing wetland impacts on a case-by-case basis, a PA outlines standardized procedures for avoiding, minimizing, and compensating for wetland loss.
• Multi-Agency Coordination – PAs often involve agencies like the U.S. Army Corps of Engineers, U.S. Fish and Wildlife Service, California State Water Resources Control Board, NGOs and regional conservation groups, ensuring that all regulatory requirements are met in one streamlined process.
• Faster Permitting for Development and Restoration – Developers and conservationists working under a PA avoid lengthy permitting delays, as their projects align with pre-approved conservation goals.

Benefits of Programmatic Agreements for Wetland Conservation

• Efficiency – Reduces project review timelines, allowing wetland restoration to begin sooner.
• Predictability – Developers and conservationists know what is required upfront, reducing uncertainty and legal risks.
• Holistic Conservation – Encourages large-scale, landscape-level restoration rather than small, fragmented mitigation efforts.
• Cost-Effectiveness – Saves money by preventing duplicative environmental reviews and litigation.

Challenges and Criticisms

While Programmatic Agreements help streamline wetland restoration and mitigation efforts, they also come with significant risks—particularly concerning over-reporting, misrepresentation, and potential fraud.

One of the most pressing concerns is that some agreements promise more wetland restoration than is actually achievable, allowing them to be used as justification for more wetland destruction than can be reasonably mitigated.

1. Over-Promising and Under-Delivering

Some Programmatic Agreements overestimate the availability of land that can be restored to functioning wetlands.

This creates a dangerous loophole where developers or agencies claim that future restoration projects will offset wetland losses, but in reality, there may not be enough viable land or resources to restore wetlands at the scale promised.

When this happens, wetland loss is effectively permanent, despite mitigation commitments on paper.

2. Mitigating More Damage Than Can Be Offset

A critical flaw in some agreements is that they allow for a greater amount of wetland destruction than can feasibly be compensated for through restoration.

Because restoration projects are often slow-moving and complex, a Programmatic Agreement may grant approvals for wetland destruction years before restoration efforts even begin, assuming that those projects will eventually balance out the damage.

In some cases, the ratio of destroyed wetlands to successfully restored wetlands is vastly disproportionate, leading to a net loss of wetlands despite regulatory compliance on paper.

3. Over-Reporting and Inflated Success Metrics

To justify new development or infrastructure projects, some agencies or mitigation banks inflate the success of their restoration efforts by using vague or misleading metrics. For example:

• Reporting acres “restored” without verifying whether the wetland is ecologically functional.
• Double-counting mitigation credits across multiple projects.
• Using low-quality or non-wetland areas as part of their mitigation acreage to meet requirements.

This kind of over-reporting gives the illusion that wetlands are being protected when, in reality, the actual ecological benefits may be minimal or nonexistent.

4. Lack of Independent Oversight and Enforcement

Once a Programmatic Agreement is in place, monitoring and enforcement can be inconsistent or weak.

If there is no third-party verification, agencies or developers can claim compliance without delivering measurable results.

Without rigorous, long-term tracking, some mitigation projects degrade over time, ultimately failing to provide the promised ecological benefits.

5. Incentives for Exploiting Loopholes

Because wetland restoration is costly and time-intensive, there is an incentive for some stakeholders to push the limits of what counts as “mitigation” under a Programmatic Agreement. This can include:

• Using low-value or marginal lands (such as seasonal ponds or grasslands) to meet restoration quotas instead of prioritizing ecologically critical areas.
• Banking future restoration credits on land that may never actually be restored to functioning wetland status.
• Using temporary mitigation measures (such as artificial water sources or short-term planting efforts) that don’t provide lasting ecological benefits.

Why This Matters

California’s wetlands are vanishing, and while billions have been spent on restoration, much of that money has disappeared into bureaucratic black holes.

Weak oversight and inflated mitigation credits allow for more destruction than restoration.

To truly protect wetlands, we need:

• Independent audits of all wetland restoration projects.
• Stronger regulations on mitigation banks.
• Public transparency in tracking wetland gains and losses.

This background guide serves as the foundation for the investigative series ahead.

We’ll expose how a system meant to save wetlands has instead become a money-making racket for a select few—and what must change to restore California’s disappearing wetlands for good.

If you haven’t already, explore our earlier installments to see the real-world consequences of these “paper restorations”:

Fake Wetland Restorations Killed California’s Delta Smelt

• Reveals how inflated restoration claims contributed to the near-extinction of the iconic Delta Smelt.
• Exposes where billions of dollars have vanished under the guise of saving a species.

Eco-Tyranny in California: Land Seized and Owner Arrested Amid Delta Smelt Scandal

• Follows the high-stakes story of one landowner who dared to question the system, only to face punishing fines and jail.
• Illustrates how bureaucratic failings can upend livelihoods and push a fragile species further toward collapse.

Stay tuned…