Photo credit: Santa Barbara Channelkeeper

Across 226 square miles, from seven tributary creeks, the Ventura River Watershed drains into the estuary in the Pacific Ocean. This river is essential for many reasons, including groundwater recharge, drinking water, recreational usage, agricultural use, and wildlife. The Environmental Resources pathway at Ventura High School has partnered with Santa Barbara ChannelKeeper’s Stream team to measure and record water quality at various points along the river.

Water quality indicators that we measured

Dissolved Oxygen (mg/L): the amount of oxygen present in the water, the relationship between temperature and dissolved oxygen is inversely proportional; often the lower the temperature, the more dissolved oxygen is in the water. Water bodies can receive oxygen from aquatic plants and the atmosphere. It is essential for aquatic life because of its role in cellular respiration. 

Turbidity (NTU): the cloudiness or haziness in water caused by particles in the water, a measure of water clarity and quality. The turbidity is affected by the amount of particles, undissolved solids, clay, sand, etc. and is typically increased by human activities like construction and agriculture that lead to erosion.

Conductivity: the ability for water to conduct electricity.

pH: the scale measuring acidity and alkalinity 

Flow (ft/sec²): Measuring the depth, width, flow of ten increments of the river and calculating the overall flow.

Procedures 

At each site, we had a set of procedures that ensured that we acquired accurate results from our data collection. Additionally to these procedures, there were a number of practices that were consistent in completing that contributed to the accuracy of our results. These practices included; 

Calibration

Calibration of our equipment for pH and conductivity entailed specific steps given on our instructions. First we turn on the machine and put the end of the device into an Oakton pH buffer solution. The first solution was 7.00 the second was 10.00. We would let the machine read it and then press the calibration button and adjust the reading as needed. The meter used for this was the Oakton 450 series. The conductivity meter was calibrated the same way just in the Oakton conductivity standard 1413. 

Taking Samples

When utilizing the meters to collect results, we made sure to take multiple readings and eliminated data that trended upwards or downwards. This practice ensured that the data recorded was accurate for that location, and had stopped increasing/ decreasing before being written down. Lastly, samples were taken early in the morning before photosynthesis could affect the results. We had several other practices during data collection. 

Turbidity

Taking our turbidity sample from upstream- to make sure the data wasn’t affected by our activity in the river.

Dissolved oxygen

For this reading we made sure to adjust the meter because this meter needed that extra step to ensure accuracy. Furthermore, we took three readings to confirm accuracy.

Conductivity

For this reading we first made sure the air bubbles were shaken out of the device to ensure accuracy. We also took three readings to ensure accuracy.

pH

For this reading we made sure the measurements were taken above the bottom of the river so only the water was being assessed. We also took three readings to ensure accuracy.

Analysis of Site Conditions

Type of Flow: A steady flow of the river ensures a stable environment and a constant volume, area, and depth of its aquatic habitat to continue to protect its aquatic life. If it is more or less, this could be more inconsistent for the ecosystem of the river.

Algae Coverage: Algae is typically dismissed as having a detrimental effect on aquatic life, but when the coverage has a natural balance, they are an important part of stream ecosystems by providing oxygen as a waste product of photosynthesis that they undergo. So having a sparse or moderate coverage of algae could be more beneficial to its environment.

Water Color: Water color can indicate high or low turbidity levels because if the nutrients or sediments in the water are super high, that will be apparent as the color of the water could become murky. Along with turbidity as a data point, this can also physically tell us that there could have been some erosion upstream or increased nutrients that could foster eutrophication.

Odors: Water that has an odor could mean that there is a harmful algal bloom and could also be a warning that there are higher bacteria levels in the water than usual. Without this indicator or a bacteria test, it would be difficult to know if the river water is harmful or not.

Garbage: Trash in the vicinity of a river ecosystem could indicate pollution being exposed to the water. This could be detrimental for aquatic life no matter the waste product, but even worse if it is a medical or chemical product. 

Ventura River above San Antonio Confluence (Site 6.3) 

By: Tiffany and Daphne

Data

Site Conditions

Analysis

DO: The minimum amount of Dissolved Oxygen for warm water is over 5 mg/L. For cold water, the preferred amount of Dissolved Oxygen is above 7 mg/L. As you can see based on our data table, the DO level on this site is in the preferred range for cold water.

pH: The preferred range of the pH levels is 6.5-8.0. The pH level in this river is right in the middle of the preferred range. With a pH level of 7.7 the river is more alkaline, or basic, rather than acidic.

Conductivity: The preferred conductivity range is 50-1500 µS in the United States. In Ventura, it is expected to be around 1000 µS or under. Our data table shows that again our conductivity level is right around the middle of that range, indicating that there’s a considerable amount of solids that were dissolved by the river.

Turbidity: The preferred range for turbidity is 0-25 NTU. Our data table indicates that the turbidity levels of this river is in the range but on the lower end, which indicates that the water was relatively clear and there was hardly any sand, silt, clay, algae or plankton present to affect the turbidity.

San Antonio Creek @ Ventura River (Site 7A)

By: Alex & Brayden

Data

Site Conditions

Analysis

Flow: The flow of the water was moving steadily with a large volume of water

Dissolved Oxygen: The Dissolved Oxygen level is above the normal level because of the cold temperature. This means that the Dissolved Oxygen level from the river is in the preferred range.

pH: The pH level was a bit higher than the neutral level because of the minerals in the water. The pH level is slightly above the preferred range.

Turbidity: The turbidity was low, with clear waters and high water movement creating a self and healthy environment for the ecosystem.

Conductivity: The conductivity at the San Antonio Creek was right in the middle of the desired range thus making it safe for local organisms.

Canada Larga at Hayden Creek (Site 4)

By: Abby and Addy

Data

Site Conditions

Analysis

DO: Data we have collected in Canada Larga reveals that this branch of the creek body contains higher levels of Dissolved Oxygen than the other locations where we sampled, however this doesn’t negatively affect the organisms living here because dissolved oxygen generally benefits aquatic organisms.

pH: As for the pH levels, a wide variety of aquatic organisms prefer a range around 6.5-8.0 pH, so the level of 8.368 indicates livable conditions. 

Turbidity: The turbidity level is on the low end of the preferred range, which contributes to a healthy environment for aquatic organisms. 

Conductivity: The healthy range for conductivity is under 3 microsiemens. The conductivity at Hayden Creek is on the higher side of this range, and this is due to the geology in the area contributing to a consistently high conductivity level.

Flow: The flow was much lower in this part of the river, which makes sense considering that Hayden creek is a smaller tributary that connects into the Ventura River.

Foster Park (VR6)

By: Celia and Caroline 

Foster Park Data

Site Conditions

Analysis: The water quality at Foster Park shows mixed results: dissolved oxygen (9.34 mg/L) is within a safe range, and pH (8.21) is high, which could stress aquatic life. Turbidity (0.58 NTU) is within safe limits, conductivity (978.9 μS) is within ideal amounts. While generally safe, the pH levels suggest that ongoing monitoring is needed to ensure the ecosystem remains balanced and healthy.

Ventura River Estuary (VR0W)

By: Riley & Brady 

Site Conditions

Type of Flow: Steady but slow

Algae Coverage: Sparse (<10%)

Odor: None

Garbage: None

Analysis

 Flow: While the amount of water moving was slow and not noticeably, there was a large volume of water that contributed to the flow result. 

Conductivity: Considering the large amounts of ocean water consistently entering the estuary, we had high conductivity from all the salts and minerals. We did not conclude that it was out of state/federal standards because we were practically testing ocean water. 

pH: pH was slightly higher than neutral, meaning the water was more alkaline. This is due to the high salinity present in the water. 

Turbidity: Turbidity was low, with minor cloudiness as a result of high water movement. 

Dissolved Oxygen: The Dissolved Oxygen is slightly above the healthy level of DO because the water temperature is lower in the fall time.

Conclusion

By: Kayla and Ryker 

Our data showed that the Ventura River is doing very well, but some areas need some attention.

All tested dissolved oxygen sites averaged well over 8 mg/L which is a good sign of a healthy river, especially seeing as to the fact that the EPA mandated minimum for clean, safe  freshwater is 5 mg/L.

Our pH readings also stayed mostly within the optimal freshwater range of 6.5 to 8.5, with our lowest reading being 7.71 (site Ventura River @ San Antonio) and our highest being 8.52 (Canada Larga @ Hayden).

Turbidity was low, meeting EPA standards, with the highest reading being 2.86 NTU (Ventura River Estuary West) , well below concerning levels.

However, conductivity was higher than the EPA's 1,000 µS guideline for some species at almost every site, except sites Foster Park and Ventura River @ San Antonio. Our highest conductivity readings were at site Canada Larga @ Hayden and site Ventura River Estuary West. The elevated readings at site Canada Larga @ Hayden are likely due to natural mineral deposits, ocean backwash, and potentially industrial runoff. The high readings at the Ventura River Estuary west is due to issues with our conductivity meter not being able to stabilize, likely due to the salt levels changing with in coming waves in the estuary. 

In conclusion, the Ventura river is very healthy, to the point where it could begin welcoming back it's once prolific stock of steelhead trout, and although there was some surprising data among the key indicators, most can be explained through simple investigations into the minerals and oil that are embedded into the local watershed.