Water Quality

3.5 Water Quality 3.5.1 Surface Water Quality ................................ 429 3.5.2 Groundwater Quality................................. 465 3.5.3 Wastewater Quality .................................. 475 3.5.4 Drinking Water Quality .............................. 485 Water Quality Sampling, Ventura River Just Above San Antonio Creek Confluence Photo courtesy of Santa Barbara Channelkeeper PART 3 • 3.5 WatER QUALITY • 3.5.1 SURFacE WatER QUALITY 429 3.5 Water Quality Water quality in the Ventura River watershed is relatively good. The developed area of the watershed is very limited compared to the open- space areas. Residential, commercial, agricultural, and industrial land Section 303(d) of the Clean uses comprise only 13% of the land area (SCAG 2008); and approxi- mately half of the watershed lies within the Los Padres National Forest. Water Act requires states to However, like most other watersheds where people live and work, the identify waters that do not Ventura River watershed has water quality impairments that need to be meet water quality standards addressed. and to classify them by The description of water quality has been organized into four sections: category. States must submit surface water, groundwater, wastewater, and drinking water. While the regulations for water quality differ for each of these water types, the their lists to the USEPA for water quality issues are often highly interrelated. review and approval. These These sections provide a review of water quality impairments, existing state-developed lists are water quality studies, the regulatory framework, and ongoing monitor- known as Section 303(d) lists ing programs. Many stakeholders, including public agencies, nonprofits, of impaired waterbodies. companies, and people who live, work, and recreate within the watershed, have been working on solutions to the watershed’s water quality issues for many years. With sufficient funding of projects (see “2.4.2 Priority Projects and Programs”), many of the water quality objectives of the stakeholder group can be achieved. 3.5.1 Surface Water Quality The surface water quality concerns that have been identified in the watershed are nutrient pollution (along with its associated problems of algal growth and low dissolved oxygen), risk of pathogens, trash, and excessive total dissolved solids. Lack of streamflow and barriers to fish migration are also considered water quality impairments in the watershed; these topics are briefly discussed in this section and are more thoroughly described in other sections (see “3.3 Hydrology” and “3.6 Ecosystems and Access to Nature”). 3.5.1.1 Surface Water Quality Impairments Algae, Nitrogen, Dissolved Oxygen, and Eutrophication Ventura River Reaches 1 and 2 and the Ventura River estuary are on the Clean Water Act’s Section 303(d) list of impaired waterbodies for algae. 430 VENTURA RIVER WATERSHED MANAGEMENT PLAN V E N T U R A C O U N T Y r. C j a i l i t a M M Fish Barriers k atil o r ija C or th F re N n ek o y n a n on C o y y y n e n l a d a Fish Barriers i C r C t G Matilija r a r a c n o Reservoir w i a e r n t r e S A N T A S a S B B A R B A R A n e k C r o re o y C e Pumping n l y l k C O U N T Y v a e o e k C e e i N r e t Water Diversion Meiners c Cree r e x C s k C R o M e e Oaks r v r F e C h e R e o Tha c m r a a e Sa nta An a r Upper c e y Cr eek u Ojai Ojai S k t n Mir a e Monte V k þ e k ·150 e ny on C ree r i on C a C L io Mercury n to n Oak ViAew Nitrogen n a Indicator Bacteria S Total Dissolved Solids Lake Casitas Cas itas ek Springs re C a g Pumping r a Water Diversion L d a Indicator Bacteria Ca ñ a ¤£101 Low Dissolved Oxygen ·þ33 Fecal Coliform Total Dissolved Solids Algae P a c Algae i f i c Eutrophic Conditions ·þ126 O c e Trash a n Total Coliform Ventur a River Ventura Estuary Miles ¤£101 ¯ 0 0.5 1 2 3 4 Montalvo Water Quality Impairments Ventura River Watershed Impaired Water Body Name Cañada Larga Creek Ventura River Estuary San Antonio Creek Ventura River Reaches 1, 2 Lake Casitas Ventura River Reach 3 Matilija Creek Reaches 1, 2 Data Source: Ventura River Reach 4 Matilija Reservoir Regional Water Quality Control Board Los Angeles Map Created by GreenInfo Network using Esri software Jan. 2015 www.greeninfo.org Figure 3.5.1.1.1 Water Quality Impairments Map Source: Regional Water Quality Control Board – Los Angeles, 303(d) List of Impaired Waterbodies PART 3 • 3.5 WatER QUALITY • 3.5.1 SURFacE WatER QUALITY 431 San Antonio Creek, Ventura River Reaches 1, 2, and 4, Cañada Larga, and the estuary are on the list for issues related to nutrient pollution: low dissolved oxygen, excessive nitrogen, or eutrophic conditions. See Figure 3.5.1.1.1 (Water Quality Impairments Map) for an illustration of the river “Beneficial uses” are the reaches and Table 3.5.1.5.1 (Water Quality Impairments by Waterbody) resources, services, and for a description of the river reaches. qualities of aquatic systems All of these listed impairments—algae, excessive nitrogen, dissolved oxygen, and eutrophic conditions—are interrelated in very complex ways. that water quality regulations aim to preserve or improve. Algae are naturally occurring organisms in aquatic habitats; however, very large blooms may hinder “beneficial uses” of aquatic systems by discour- They include recreation; aging recreation, altering natural habitats, or diminishing environmental water supply; navigation; conditions. For example, algal respiration at night and the decomposition and the preservation and of large algal blooms, can decrease dissolved oxygen concentrations in enhancement of fish, wildlife, water. If severe, decreases in dissolved oxygen may affect the survival of fish (including their eggs), aquatic insects, or other aquatic life. Lack of and other aquatic resources. streamflow or water circulation, and high water temperatures, can also lower dissolved oxygen concentrations, independently of algae. Beneficial uses can be existing, The growth rate of algae in an aquatic system depends on the amount potential, or intermittent uses. of sunlight; water depth, temperature, and circulation; nutrients; con- sumption of algae by aquatic animals (e.g., insects, snails, fish); and other variables. In streams, the availability of logs, rocks, or other stable mate- rial for attachment also affects the amount and type of algae that will grow. During warmer months, when conditions are favorable for algal growth, conspicuous blooms of algae may occur. Researcher Studying Algal Bloom (Cladophora) in Matilija Creek, March 2010. Location: 1.5 miles above Matilija Dam, in the relatively undevel oped headwaters of the Ventura River. Algae are naturally occurring, even in the undeveloped upper watershed, where nitrate concentrations are low. Photo courtesy of Diana Engle 432 VENTURA RIVER WATERSHED MANAGEMENT PLAN Algae Growth Can Vary Significantly in Different Years Top left: Above Highway 150 Bridge in 2008, a big algae year. Photo courtesy of Santa Barbara Channelkeeper. “2008 was a very big algae year in the watershed. Big algal years invariably follow winters with aboveaverage rainfall, winters with at least one storm big enough to sweep aquatic plants and accumulated fine sediment out to sea; even better if that storm is large enough to also clean out riparian growth. These storms create nearperfect algal habitat by: 1) opening up the channel to increased sunlight (sunlight to power photosynthesis—even more sunlight if riparian vegetation is cut back or removed); 2) removing competitors (for sunlight, e.g., aquatic plants) and algal parasites; 3) scouring the stream or river bottom leaving only gravel or cobble (provid ing necessary holdfasts—anchoring points—for Cladophora, the dominant alga during big blooms); and 4) increasing flow (expanding available habitat and providing for more rapid delivery of streamborne nutrients to stationary algae).” (Leydecker 2012b) Bottom left: Above Highway 150 Bridge in 2006, following the big storm year of 2005. Photo courtesy of Jeff Palmer. Below: Abundant aquatic plants outcompete algae down stream of Ojai Valley Sanitary District effluent discharge, 2009. This site exhibited little algae growth in May 2009 due to the abundant growth of aquatic plants that outcompeted algae for substrate and reduced sunlight to the flowing channel. Photo courtesy of Santa Barbara Channelkeeper. PART 3 • 3.5 WatER QUALITY • 3.5.1 SURFacE WatER QUALITY 433 The frequency, duration, and intensity of algal blooms can be increased when excess nutrients are available; however, many other factors affect the intensity of algal blooms. Impressive algal blooms have been witnessed in Regulations called TMDLs, the upper watershed with low levels of nitrogen but plenty of sunlight and for Total Maximum Daily calm waters. Other sites where nutrient levels are high, but the water is Loads, are developed to shaded by aquatic plants or trees, may not experience algal blooms. address the impairments The watershed’s most serious algae problems typically occur early in the dry season following a winter with high rainfall, when significant storm caused by pollutants. flows have ripped out aquatic plants and riparian vegetation, leaving bare rock and gravel with plenty exposed to the sun. Another effect of TMDLs for pollutants outline excess nutrients is rapid growth of all vegetation, including the aquatic the loading (e.g., “pounds plants that soon dominate the stream bottom after drier winters (Klose per day”) or concentration et al., 2009).

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