«225 «146. ^_ Texas Stream Team. !. Monitoring Station. "/ USGS Flow Station # Wastewater Outfall. Location Map. Morgan's Point. La Porte.

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1 95 5'0"W UPPER CEDAR GALVESTON BAYOU TIDAL BAY - - SEGMENT '0"W 94 55'0"W 94 50'0"W 29 45'0"N 29 45'0"N Trinity Bay «225 Tabbs Bay Location Map 29 40'0"N SPENCER HWY Big Island Slough SENS RD S BROADWAY ST Morgan's Point La Porte HARRIS COUNTY CHAMBERS COUNTY '0"N AIRMONT PKWY Shoreacres Upper Galveston Bay '0"N Number of Outfalls: 38 Total Population , (Proj.) 36, (Proj.) 69,064 «146 Seabrook '0"N '0"N 29 25'0"N Watershed Boundary!. Monitoring Station Nassau Bay ^_ Texas Stream Team "/ USGS Flow Station # Wastewater Outfall Major Road Waterway County League Boundary City City, Town or Place Land Cover (2008) Ü 0 Jarbo Bayou High Intensity Developed Low Intensity Developed Open Space Developed Cultivated Grassland/Shrub Forest Woody Wetland Herbaceous Wetland Bare Open Water 1 2 Miles Kemah FM 646 Bacliff Dickinson Bayou Tidal Texas City Moses Bayou San Leon CHAMBERS COUNTY GALVESTON COUNTY Assessment Stations for the 2010 Texas Integrated Report Use Impairment PCBs & Dioxin Bacteria in Oyster Waters Area of Impairment PCBs & Dioxin ID 15243, 15244, 15245, 15904, 15907, 15908, 15910, 15913, 15242, 15246, 15247, 15903, 15906, 15909, 15911, 16201, 16203, 16207, 16208, 16503, 16507, 16510, 16511, 16512, 16516, , 15904, 15907, 16201, 16203, Kilometers PCBs & Dioxin, Bacteria in Oyster Waters '0"N 29 25'0"N e 95 5'0"W 95 0'0"W 94 55'0"W 94 50'0"W

2 Segment Number: 2421 Name: Upper Galveston Bay Contact Recreation; High Aquatic Life Use; Oyster Area: square miles Miles of Shoreline: 35.2 miles Designated Uses: Waters Number of Active Monitoring Stations: 9 Texas Stream Team Monitors: 3 Permitted Outfalls: 21 A square kilometer (108.2 square mile) portion of Galveston Bay located entirely between Chambers and Harris Counties extending southward from the vicinity of Morgan s Point to an imaginary east west line in the area of Redfish Island off Eagle Point Description: and extending eastward to Smith Point in Chambers County, then north on an imaginary north south line extending to Beach City Sub Segment 2421A: Clear Lake Channel (unclassified water body) From the Lower Galveston Bay confluence to SH 146 Degree of Impairment and Overall Trends Segment ID Dissolved Oxygen Bacteria Nutrients PCBs/Dioxin Chlorophyll a Other A Indicates general improvement Indicates general degradation Numbers indicate percent of segment impaired FY 2011 Active Monitoring Stations Site ID Site Description Frequency Monitoring Entity Parameter Groups Pine Gully at Todville Road Quarterly TCEQ Field, Conventional, Bacteria, Chlorophyll a Upper Galveston Bay at 97gb008 Quarterly TCEQ Field, Conventional, Bacteria, Chlorophyll a Upper Galveston Bay at 97gb008 Once / Year TCEQ Benthics, Metals in Sediment Upper Galveston Bay at 97gb013 Quarterly TCEQ Field, Conventional, Bacteria Upper Galveston Bay at 97gb013 Once / Year TCEQ Benthics, Metals in Sediment Upper Galveston Bay at 97gb014 Quarterly TCEQ Field, Conventional, Bacteria, Chlorophyll a Upper Galveston Bay at 97gb014 Once / Year TCEQ Benthics, Metals in Sediment Upper Galveston Bay at 97gb015 Quarterly TCEQ Field, Conventional, Bacteria, Chlorophyll a Upper Galveston Bay at 97gb019 Quarterly TCEQ Field, Conventional, Bacteria, Chlorophyll a Upper Galveston Bay at 97gb019 Once / Year TCEQ Benthics, Metals in Sediment Upper Galveston Bay at 97gb021 Quarterly TCEQ Field, Conventional, Bacteria, Chlorophyll a Upper Galveston Bay at 97gb036 Quarterly TCEQ Field, Conventional, Bacteria, Chlorophyll a Upper Galveston Bay at 97gb036 Once / Year TCEQ Benthics, Metals in Sediment Little Cedar Bayou at S Broadway Street Quarterly TCEQ Field, Conventional, Bacteria, Chlorophyll a

3 Segment 2421 Standards Screening Levels Temperature ( C): 35 Ammonia N (mg/l): 0.10 Dissolved Oxygen (24 Hr Average) (mg/l): 4.0 Nitrate N (mg/l): 0.17 Dissolved Oxygen (Absolute Minima) (mg/l): 3.0 Orthophosphate Phosphorus (mg/l): 0.19 ph (standard units): Total Phosphorus P (mg/l): 0.21 Enterococci (MPN/100mL) (grab): 89 Chlorophyll a (µg/l): 11.6 Enterococci (MPN/100mL) (geometric mean): 35 Fecal Coliform in Oyster Waters (CFU/100mL) (median/grab): 14/43 Water Quality Issues Summary Issue 2008 Assessment Draft 2010 Assessment Affected Area Possible Causes/Influences / Concerns Voiced by Stakeholders Possible Solutions / Actions To Be Taken Elevated Levels of Bacteria in Oyster Waters I I Entire segment WWTP non compliance, overflows, collection system by passes Small, privately run WWTP Developments with septic tanks Rapid urbanization and increased impervious cover Constructed storm water controls failing Direct and dry weather discharges Waste haulers illegal discharges/improper disposal Improper or no pet waste disposal Bird rookeries on islands throughout the bay and along the shoreline Improper disposal of waste from boats Increase monitoring requirements for selfreporting Impose new or stricter bacteria limits than those designated by TCEQ Require all systems to develop and implement a utility asset management program and protect against power outages at lift stations or provide alternative power supplies during outages Regionalize wastewater treatment to prevent or minimize number of small package plants and reduce septic tank dependency Require larger partials of land in developments platted to use OSSF More public education regarding OSSF operations and maintenance More public education regarding pet waste Improve storm water controls in new developments by adding bacteria reduction measures

4 Dioxin/PCBs I I Entire segment Waste pit located along the San Jacinto River immediately upstream of I 10 bridge is now a National Priority List Superfund site managed by EPA Concentrated deposits outside boundaries of the waste pits Unknown industrial or urban sources Improve compliance and enforcement of existing storm water quality permits to minimize contaminated runoff Improve construction oversight to minimize TSS discharges to waterways. Promote and implement Water Quality Management Plans for individual agricultural properties Encourage EPA and responsible parties to work together to remediate Superfund site Remove or contain contamination from locations already identified Encourage additional testing to locate all unknown sources/deposits Elevated Nutrients Elevated Chlorophyll a Concentrations C C Entire segment WWTP effluent, sanitary sewer overflows, and malfunctioning OSSFs Agricultural runoff from row crops, pastures, and fallow fields Fertilizer runoff from urbanized properties such as landscaped areas, residential lawns, and sport fields C C 2421 Fertilizer runoff from surrounding watershed promote algal growth in waterways Nutrient loading from WWTPs effluent, sanitary sewer overflows, and malfunctioning OSSFs promote algal growth If DO swings are significant and biology shows a related effect, some phosphorus controls may be needed for wastewater treatment plants Implement YardWise and Watersmart landscape practices Improve storm water controls in new developments Improve compliance and enforcement of existing storm water quality permits. Support/continue/initiate public education regarding nutrients and consequences

5 Elevated Heavy Metals Iron in sediment C 2421 Discharges from domestic, agricultural or industrial sources Build up in pipelines, pressure tanks, water heaters and water softeners from industrial point sources Particle deposition and resuspension processes due to dredging processes or tidal movements Dissolution from natural deposits Increase monitoring and enforcement efforts to identify and control industrial point sources Encourage additional testing to locate all unknown sources/deposits Segment Discussion: Watershed Characteristics: The upper portion of this watershed contains a lot of industrial land uses and a mixture of residential and commercial uses in the cities of La Porte, Shore Acres, and Pasadena. The southern portion of the watershed is predominantly residential and commercial uses in the cities of Seabrook and Kemah and in unincorporated Harris and Galveston counties. The area is heavily used for recreational uses such as fishing and boating. The area has become more heavily developed along the coast in the past five years with forested lands being replaced by residential developments. Water Quality Issues: While this segment is fully supporting of its contact recreation use, however, all portions of Upper Galveston Bay have been closed to harvesting of oysters by the Texas Department of State Health Services. Therefore, it does not support a use for oyster waters. According to the 2008 Texas Integrated Report (IR), nitrate nitrogen (nitrate) was a concern for the three assessment units of the main segment. On the main segment, 47% of the samples (98 out of 209) exceeded the nitrate level of 0.17 mg/l. However, the Draft 2010 IR does not list nitrate as a concern for the assessment unit of the eastern portion of the bay. Although ammonia nitrogen (ammonia) was listed as a concern in the 2008 IR in the assessment unit closest to the coastal portion of the bay with 31% (12 out of 39 samples) exceeding the level of 0.10 mg/l, it is not listed as a concern for ammonia in the Draft 2010 IR. Ammonia is listed as a concern for the unclassified segment 2421A (Clear Lake Channel) with 83% (10 out of 12 samples) exceeding the level. All three assessment units of the main segment have a concern for total phosphorus (TP) with 51% (109 out of 213 samples) exceeding the level screening level of 0.21 mg/l. TP is also a concern for 2421A, with 63% of the samples (five out of eight) exceeding the level screening. Chlorophyll a has been listed as a concern for the three main assessment units of the main segment. According to the data set taken from December 2001 to November 2008, 72% of the samples (152 out of 211) exceeded the chlorophyll a level standard of 11.6 µg/l. The Draft 2010 IR lists all three assessment units of the main segment with a concern screening for iron in the sediment with 100% of the samples (19 out of 19) exceeding well above the level of 3.70 mg. The Texas Department of State Health Services has also listed a fish consumption advisory for the entire watershed for PCBs and dioxin in fish tissue.

6 Special Studies/Projects: This segment is included in three TMDL projects: the Houston Ship Channel and Upper Galveston Bay TMDL for PCBs in Fish Tissue, the Houston Ship Channel TMDL for Dioxin, and the Galveston Bay System Survey for Dioxin and PCBs, which are currently under way. For more information, please refer to the detailed discussions located at the beginning of the water quality section of the 2011 Basin Summary Report regarding Dioxin and PCB contamination. Trends: The Draft 2010 IR identifies impairments related to PCB and dioxin compounds, and bacteria in oyster waters in Upper Galveston Bay. The segment is also listed for nutrient concerns. Analysis of pooled data revealed statistically significant upward trends for chlorophyll a concentrations, dissolved oxygen (DO), and ph, while suggesting a negative trend for total suspended solids (TSS). The chlorophyll a trend exhibited at the watershed level is strongly supported by station level data. The analysis of individual sample results suggested statistically significant positive trends at 25 of the 29 stations in the watershed where chlorophyll a concentrations are monitored. Analysis of annual median concentrations produced evidence that concentrations are increasing over time at 18 stations. The pattern for associated nutrients is more complex. Analysis of individual sample results suggests that nitrate concentrations are declining at five stations, TP concentrations are declining at two and increasing at two stations, while orthophosphate phosphorus (OP) concentrations are declining at three and increasing at two stations. However, the stations in Upper Galveston Bay have not been monitored frequently over the period of record, and there are typically 12 to 15 data points for each parameter per stations with significant temporal gaps. While one should be cautious when interpreting these trends, there seems to be sufficient evidence to warrant continued concern. Graphs of chlorophyll a, TP, and nitrate for station follow. Recommendations: Increase the number of yearly representative stations to provide consistent time series. Need fewer stations with more data. Support Galveston Bay Foundations efforts to complete Oyster Waters TMDL on this segment. Address the various concerns found in this segment summary through stakeholder participation. Continue collecting water quality data to support actions associated with future watershed protection plan development and/or modeling. Work with local partner and contract labs to lower detection limits for nutrients.

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