I am just back from a couple of days visiting south of Barahona and decided to visit Laguna Oviedo after tour report above, and for that many thanks.
Firstly Los Patos. The river is indeed longer than 61 meters now. It finds it way to the sea behind the pebble dunes right up at the point leading to Paraiso, and that is a fair treck walking on the smaller pebbles. Being the weekend the river ponds were absolutely full with visitors from all over the country. There was one bus from La Romana. For visitors and bathers the tourist attraction has been set up really well, with good parking, board walks all around and onto the beach with pergolas, and several well constructed vendors pavilions selling food and drink to the mass of tables set under the trees bordering the river ponds. Typically Dominican with families and all enjoying music, drink, food, and the cool clear river water. The sea on Saturday was calm and very swimmable and at the foot of the pebble dunes is a very coarse sand. There are occasional sandy spots along the beach. But the overall vista is exceptional with a turquoise sea out some 100 meters even when the rollers were pounding in on the Saturday. As you say taking in the views either approaching Los Patos from the north or the south are spectacular.
We had fish prepared Sunday away from the crowds in the small shack of a restaurant a short distance to the south of the river where the fisherman's boats sit. I noticed this was attracting some of the Santo Domingo folk in smart cars. The fish was cooked on a coal fire to absolute perfection and there was a hint of oregano amongst the perfect texture. The salad was exceptional too along with chillingly cold beer. I would recommend this place to anyone and the local couple and family who run it deserve credit for keeping it simple in such surroundings.
We also took lunch at a small Italian place in the town. Unassuming but he knows how to prepare a simple cheap pasta. Stayed at the cheap but very simple Italian run hotel which was full and turning away people Saturday.
We visited Laguna Oviedo on the Sunday and the entrance is as you say signposted just before you enter the town. We decided to do the full lake tour with guide and that costs 3500rd for a two to two and half hour trip on the dirty looking greeny brown lake (there are several options posted and priced at the reception centre). There is a 100rd per person park fee and for that you get a green 'AI' wrist band. The yola we took had a canopy and frankly as he was whipping across the lake firstly to the islands, the wind in your face and very salty water splashing you in a stiff breeze made you feel cool.
If you are into bird watching this place will be heaven. If not you might be very impressed. (If you only come to DR for the other variety forget this place.) Our guide was very helpful and was pointing out all the birds with the help of a plastic card givig their names. He also offered use of his binoculars. One island has no birds and not surprisingly it is because it is home to rather large inquisitive iguanas who apparently have a likely for 'huevos'.
The flamingoes are found at the other end of the lake near the point where a river enters the laguna. There were two groups. The first of about 100 birds were not camera shy and went about thee elegant wading as out boat captain pushed us quietly towards them. Only ten were pink. Flamingoes apparently get the pink colour from the algae they eat and Oveidos flamingoes have taken a liking to shrimp from the river entering nearby. The second group were almost all a whiter shade.
The lake is very shallow with plenty of weed so the boat captain has to contantly clear his propellers durig the trip and weaved between stick markers he and his colleagues have placed around the lake.
For us the visit was well worth it.
Our guide who works for the tourism ministry was very helpful and informative and offered his services for several other excursions discussed. He told us that there were many more flamingoes to be found at Lagos Salado anDulce to the south but access was more difficult by pre arranged four hour horse trip. He also told us of a clear water pond in amongst the woods a few kilometers on the way back to Los Cocos and we found it with a bunch of locals cooling off for the weekend.
The new wind turbines at Parqueo Eolico are sited on hgher ground way up into the hills beyond the existing wind farms at Los Cocos and it is an impressive sight.
One final point to mention on our return to the city today was that we found the cooperative at La Cienega and bought one of each of the five marmalades they make: Mango, Guanabana, Chinola/Guineo, Naranga Amarga and Guayaba. Will be trying these over the coming days.