As they have in the past, North County beaches generally fared well Tuesday in an environmental group's latest report card on water quality along the California coast.

Some grades for winter water quality improved over last year. But the report showed that there are still problems when winter storms wash pollution down creeks and into the ocean.

Every year, the Santa Monica group Heal the Bay releases an analysis a few days before the Memorial Day holiday weekend to inform swimmers and surfers of the risks they may face as millions flock to the shore during the unofficial start of the summer recreation season.

The report covers 500 beaches statewide.

A poor grade generally means there is an elevated risk of people getting stomach flu, ear infections, upper respiratory infections and skin rashes by going into the water.

The beaches receiving the worst grades land on the group's "Top 10 Beach Bummers" list.

North County beaches avoided the dubious distinction of being saddled with the unflattering "bummer" status, according to the group's 88-page report. The list was dominated by beaches in Los Angeles and Orange counties.

Heal the Bay issued separate grades for water quality during the summer, when the water tends to stay relatively clean in most places, and for the winter during the days immediately following storms when water is laced with fertilizer, trash, oil and bacteria.

Winter grades for several beaches in Oceanside where creeks and rivers meet the ocean were higher than in 2008, the report shows. Only one beach -- Buccaneer -- was hit with a failing grade yet again.

But because of a lapse in state funding, water quality monitoring was dramatically scaled back in San Diego County between November and March. And no information was available for those crucial post-storm periods for many local beaches.

Here are the North San Diego County results:

- San Onofre State Beach at San Mateo Creek: A+ for summer; no winter grade.

- San Onofre State Beach at San Onofre Creek: A for summer; no winter grade.

- Oceanside, Harbor Beach: A for summer, A+ for winter.

- Oceanside at San Luis Rey River: A for summer; A+ for winter.

- Oceanside at Surfrider Way: A+ for summer; A+ for winter.

- Oceanside Municipal Pier: A+ for summer; A+ for winter.

- Oceanside at Tyson Street: A+ for summer, C for winter.

- Oceanside at Forster Street: A+ for summer, D for winter.

- Oceanside at Loma Alta Creek: A+ for summer; D for winter.

- Oceanside, Buccaneer Beech: A+ for summer; F for winter.

- Oceanside at Cassidy Street: A+ for summer; B for winter.

- Carlsbad Village: A+ for summer; no winter grade.

- Carlsbad at Tamarack Avenue: A+ for summer; no winter grade.

- Carlsbad at Palomar Airport Road: A+ for summer; A+ for winter.

- Carlsbad at Encina Creek: A+ for summer; A+ for winter.

- Carlsbad at Ponto Drive: A+ for summer; A+ for winter.

- Carlsbad at Poinsettia Lane: A+ for summer; A+ for winter.

- Encinitas, Moonlight Beach: A for summer; no winter grade.

- Encinitas, Swami's Beach: A+ for summer; no winter grade.

- Encinitas, San Elijo State Park: A+ for summer; no winter grade.

- Cardiff State Beach, San Elijo Lagoon: A for summer; no winter grade.

- Cardiff State Beach, Seaside State Park: A+ for summer; no winter grade.

- Solana Beach, Tide Beach Park: A+ for summer; no winter grade.

- Solana Beach, Fletcher Cove: A+ for summer; no winter grade.

- Solana Beach, Seascape Surf Beach Park: A+ for summer; no winter grade.

- Del Mar at San Dieguito River: A for summer; no winter grade.

- Del Mar at 15th Street: A+ for summer; no winter grade.

- Torrey Pines, Los Penasquitos Lagoon: A+ for summer; no winter grade.

To view the report, visit www.healthebay.org.

Contact staff writer Dave Downey at 760-745-6611, Ext. 2623.