East Park Reservoir

SWIMMING ADVISORY

Recently, our department was notified that over the last weekend, patrons using the water at East Park Reservoir—particularly in marshy areas or spots with abundant aquatic plant life—developed a rash resembling swimmer’s itch.

Before your upcoming booking, we would like to offer safety tips for enjoying the water. Swimmer’s itch, also known as cercarial dermatitis, is a skin rash caused by an allergic reaction to microscopic parasites released by snails into both freshwater and saltwater environments (such as lakes, ponds, and oceans). Although humans are not the parasites’ preferred hosts, exposure to these parasites while swimming can trigger an allergic reaction that results in a rash.

Swimmer’s itch occurs worldwide and is most common during the summer months. It is not contagious and cannot be spread from person to person. Although not everyone who is exposed to the parasites develops the rash, prolonged contact with water known to harbor these organisms increases an individual’s risk. Consequently, children are more susceptible because they often wade in recreational waters for extended periods and may not dry off thoroughly after swimming.

The following symptoms may indicate swimmer’s itch:

• Tingling, burning, or itching: These sensations may develop within minutes or days.

• Reddish pimples: Small, reddish pimples may appear on the skin within about 12 hours.

• Blister formation: Small blisters may develop at the sites of the pimples shortly afterward. While the urge to scratch is common, doing so can lead to infection. Although the itching usually subsides quickly, relief measures should be considered.

Most cases do not require medical attention. However, if the rash persists or worsens, the CDC recommends the following relief measures:

• Apply corticosteroid cream.
• Use cool compresses on the affected area.
• Bathe in Epsom salts or baking soda.
• Soak in colloidal oatmeal baths.
• Apply a baking soda paste to the rash.
• Use an anti-itch lotion.

If scratching leads to an infection, contact your health care provider immediately.

To reduce the risk of swimmer’s itch, consider these preventive measures:

• Towel dry and shower immediately after leaving the water. Be sure to thoroughly rinse areas beneath the bathing suit.

Multiple factors contribute to the development of swimmer’s itch in recreational waters. Because there are no tests available to determine the presence or absence of the parasites, it remains unclear how long an affected water body may remain a risk.

Public Notice: East Park Reservoir Invasive Species Prevention

East Park Reservoir now has a mandatory self-certification process in place as of May 20, 2025. This requires ALL boat owners to self-certify their water crafts per the inspection form. The completed and signed form must be placed on the dashboard of the towing vehicle, and in plain sight for County Staff or Bureau of Reclamation staff to view. This is related to the statewide Golden Mussel Prevention Program

Each boat owner must perform the following:

1. Download, complete, and sign the Self Certification form which can be accessed HERE.
2. Place the form on the dashboard of the vehicle towing your watercraft.
3. Park the vehicle such that the completed and signed self-certification form is visible for County or Bureau of Reclamation staff to view.
4. If you are not able to self-certify your watercraft, DO NOT LAUNCH YOUR BOAT OR WATERCRAFT. You must clean your watercraft and wait the mandatory times for it to completely dry.
5. If you are unable to self certify your watercraft, or if you find or suspect your watercraft is infected with the invasive muscles, you MUST HAVE YOUR WATERCRAFT STERILIZED BY AN APPROVED MUSSEL DECONTAMINATION STATION. Please contact the California Department of Fish and Wildlife at: 1-888-326-2822.

Standard good boat hygiene includes the following:

1. Clean: Thoroughly wash your boat, trailer, and any equipment that has come into contact with water. This includes scrubbing off mud, plant debris, and any visible organisms.
2. Drain: Remove all water from your boat’s live wells, bilges, and compartments to eliminate any potential hitchhikers.
3. Dry: Allow your gear to dry completely on land for several days, as many invasive species cannot survive extended periods out of water.
4. Inspect: Regularly check your equipment before and after each use, especially when moving between bodies of water known for invasive species risks.
5. For further details on invasive species prevention and best practices, please consult local water resource management guidelines or visit their website at:

Don’t Move A Mussel Card

Aquatic Invasive Species

Invasive Golden Mussel

Quagga & Zebra Mussels

Opening Day: Friday April 18, 2025

To stay updated on reservoir details, sign up for our emails here: SUBSCRIBE

or call: Colusa County Public Works office: 530-458-0466 Monday-Friday 7:30am-4:00pm

Connect with us on Facebook AND INSTAGRAM to hear about East Park experiences from our friends on social media!

Sign up below to get East Park Reservoir updates sent straight to your inbox.

---